Dec. 9, 2005 - Nasa: Fill & Download for Free

What does your "Your Content" page for the Astronomy topic look like?Anonymous • Added in Astronomy • Just nowWhat does it mean that the solar system is nearly full, in the sense that there are few places where we could insert an additional planet without causing immediate instability?Anonymous • Added in Astronomy • 26 JulHow hot will the outer planets (Jupiter, Saturn, Uranus, Neptune) become once the sun turns into a red giant?Added in Astronomy • 26 JulWhat is a first-order approximation for the equation of state of a main sequence star?Followed in Astronomy • 20 JulHow can we recruit more astronomers onto Quora?Added in Astronomy • 12 JulWhat factors determine how much a star's rotation will slow down with age?Added in Astronomy • 12 JulIs there an RA/dec map of the Mollweide projection of galaxies in the sky?Added in Astronomy • 11 JulWhy does the Moon's daytime temperature deviate from the planetary equilibrium temperature of the Earth?Added in Astronomy • 5 JulWhat are some of the most interesting features that can be seen in a map of the cosmic microwave background (CMB)?Added in Astronomy • 4 JulWhat types of large-scale models/simulations are used in astrophysics research?Added in Astronomy • 30 JunHow will the Large Synoptic Survey Telescope (LSST) change astrophysics research?Added in Astronomy • 22 MayYour answer to Where can I find an academic position in astronomy or astrophysics in the US in 2014?Added in Astronomy • 17 MayWhere is entropy the greatest: at the centre of a star, or in its corona?Followed in Astronomy • 11 MayWhat can experimental neuroscience learn from experimental techniques in astronomy?Followed in Astronomy • 2 MayYour answer to Will Venus be tidally locked to the Sun?Added in Astronomy • 17 AprWhy isn't there much stellar astrophysics research these days?Added in Astronomy • 12 AprYour answer to Planetary Science: What is currently considered the best textbook for solar system studies?Added in Astronomy • 7 AprDo we have a map of the B-mode polarization as measured by BICEP2?Anonymous • Added in Astronomy • 25 MarWhy is the distribution of discovered exoplanets highest towards the center of the galaxy and in the direction of our solar system's movement?Followed in Astronomy • 24 MarYour answer to How can you detect life on Earth from space?Added in Astronomy • 18 MarIs it easier to study planetary systems that we see from the side or the top?Followed in Astronomy • 15 MarAre astronomy PhD students generally happier than Physics PhD students?Added in Astronomy • 12 MarIs there a form of precession for the Earth's orbital plane with respect to the invariable plane of the Sun?Added in Astronomy • 8 MarYour answer to Is there a geographical coordinate system for our solar system?Added in Astronomy • 8 MarWhat is Nobelist John Mather's vision for the James Webb Space Telescope and the future of astrophysics?Followed in Astronomy • 8 MarWhat is the current state of research going on in the field of exoplanets?Followed in Astronomy • 8 MarYour answer to What is it like to study Astronomy at the University of Washington?Added in Astronomy • 27 FebWhat is it like to be a graduate student in astrophysics at Princeton?Followed in Astronomy • 21 FebDoes the sun's position affect cloud formation?Followed in Astronomy • 21 FebYour answer to Are new stars being born at the same rate as the death of old stars?Added in Astronomy • 13 FebWhat is it like to study physics & astronomy at Northwestern?Followed in Astronomy • 7 FebWhat is it like to study Astronomy at Northwestern?Added in Astronomy • 7 FebHow are so-called hypervelocity stars ejected from a galaxy by means of a supernova explosion?Followed in Astronomy • 29 Dec, 2013What are the similarities and differences between astronomical imaging and biological imaging?Added in Astronomy • 28 Dec, 2013What is it like to study Astronomy at Columbia?Added in Astronomy • 23 Nov, 2013What is it like to study Astronomy at Harvard?Added in Astronomy • 23 Nov, 2013How is time-series analysis used in astronomy?Added in Astronomy • 22 Nov, 2013Your answer to Astronomy: Is there a galactic "goldilocks zone" for habitable planets?Added in Astronomy • 14 Nov, 2013What are the strongest schools for planetary science?Added in Astronomy • 13 Nov, 2013Why is the frequency of plasma waves in the interstellar medium higher than that of plasma waves within the solar heliosphere?Added in Astronomy • 11 Nov, 2013Is the excessive use of IDL and IRAF among astronomers holding back progress in astronomy?Added in Astronomy • 9 Nov, 2013How prevalent is student unhappiness in Astronomy PhD programs?Added in Astronomy • 9 Nov, 2013Your answer to Astrophysics: What are the similarities and differences between Physics, Astrophysics, and Earth and Planetary Science?Added in Astronomy • 9 Nov, 2013Why don't more astronomers use Python?Added in Astronomy • 9 Nov, 2013Your answer to Educational Resources: Where can I get an awesome educational experience in geology or planetary geology?Added in Astronomy • 13 Oct, 2013How does a star's heliosphere scale with the star's distance from the center of the galaxy?Added in Astronomy • 4 Oct, 2013How does the size of the solar heliosphere affect the flux and energy distribution of cosmic rays hitting the Earth?Added in Astronomy • 4 Oct, 2013How does the cosmic ray flux and intensity on red dwarf planets compare with the cosmic ray flux and intensity on planets around the Sun?Added in Astronomy • 4 Oct, 2013Is IDL dying? If so, why?Added in Astronomy • 23 Sep, 2013Does the solar heliopause protect life against galactic radiation?Added in Astronomy • 20 Sep, 2013How much money is there in earth/atmospheric/planetary science?Added in Astronomy • 6 Sep, 2013How much money is there in astronomy?Added in Astronomy • 6 Sep, 2013Can rogue planets support life?Followed in Astronomy • 1 Sep, 2013What is it like to be a graduate student in astronomy?Added in Astronomy • 31 Aug, 2013What is the easiest way for me to meet a bunch of Astrophysics professors in order to determine ideal personality fit in a PhD adviser?Added in Astronomy • 12 Aug, 2013Is it true that the Caltech/Harvard/Princeton astronomy departments are kind of an "exclusive/elite" club?Added in Astronomy • 11 Aug, 2013How is machine learning used in astronomy & astrophysics?Added in Astronomy • 11 Jul, 2013What are the biggest complaints that astronomers have about how astronomy is practiced?Added in Astronomy • 6 Jul, 2013What video games use a real-life model of stars in the Milky Way (or the Local Group/Virgo Supercluster/etc) for their game world?Added in Astronomy • 19 Jun, 2013Should graduate students in astronomy count as having recognized topic biographies in Physics?Added in Astronomy • 30 May, 2013How messy are astronomy datasets compared with climate science datasets?Added in Astronomy • 28 May, 2013How messy are most datasets in astronomy?Added in Astronomy • 28 May, 2013How well does an astrophysics background prepare one for positions in data science?Added in Astronomy • 28 May, 2013How can a high school student prepare themselves to become an astronomer?Added in Astronomy • 28 May, 2013How can I massively visualize SDSS data?Added in Astronomy • 28 May, 2013★Can you do observational astronomy by just doing data-analysis on massive astronomy datasets like SDSS datasets? (without ever using a telescope)?Added in Astronomy • 19 May, 2013Which planet spends the greatest share of time closest to Earth: Venus, Mars or Mercury?Followed in Astronomy • 19 May, 2013What are the similarities and differences between climate re-analysis and observational astronomy?Added in Astronomy • 19 May, 2013What branch of astronomy/astrophysics would be closest in research style to climate modeling?Added in Astronomy • 19 May, 2013How does the culture of physics compare with that of astronomy?Added in Astronomy • 19 May, 2013When will there be another Kepler Telescope?Added in Astronomy • 16 May, 2013How computational is most observational astronomy research?Added in Astronomy • 16 May, 2013Which members of Quora have expertise in astronomy/astrophysics?Added in Astronomy • 5 May, 2013How does the physics of neutron stars compare and contrast with the physics of white dwarfs?Added in Astronomy • 29 Apr, 2013How does the happiness of PhD students in Physics compare with that of Astronomy?Added in Astronomy • 31 Mar, 2013How does the happiness of PhD students in geosciences compare with that of astronomy?Added in Astronomy • 31 Mar, 2013How did UC-Santa Cruz become so amazing in Astronomy?Added in Astronomy • 25 Mar, 2013What are the various applications used for Astronomy, what are their advantages, and what are their disadvantages?Added in Astronomy • 24 Mar, 2013What are some examples of publicly available datasets in astronomy?Added in Astronomy • 22 Mar, 2013What can an undergrad do to prepare for graduate school in Astronomy?Added in Astronomy • 10 Mar, 2013How has the rate of return in terms of science per dollar spent changed in investments in astronomy over the last few decades? And how will it change in the future?Added in Astronomy • 10 Mar, 2013How has the rate of return in terms of science per dollar spent changed in investments in exoplanets over the last few decades? And how will it change in the future?Added in Astronomy • 10 Mar, 2013What percent of grants in astronomy come from NASA, what percent come from NSF, and what percent come from other sources?Added in Astronomy • 10 Mar, 2013What is the difference between Rosseland and Planck mean opacities?Added in Astronomy • 4 Mar, 2013What are the similarities and differences between ncdata files in climate science and FITS data files in astronomy?Added in Astronomy • 3 Mar, 2013Could IRAF be replaced with something else?Added in Astronomy • 24 Feb, 2013Why don't more astronomers use MATLAB?Added in Astronomy • 24 Feb, 2013What should every astronomy PhD student know how to do?Added in Astronomy • 7 Feb, 2013What is an intuitive explanation of the Toomre stability criterion?Added in Astronomy • 31 Jan, 2013Would heat from a red giant star be sufficient enough to drive a different form of plate tectonics on a planet around a red giant star?Added in Astronomy • 29 Jan, 2013How are supernovas simulated?Added in Astronomy • 9 Jan, 2013★How are the interior structures of stars simulated?Added in Astronomy • 9 Jan, 2013Could life exist on the outskirts of a brown dwarf's atmosphere?Added in Astronomy • 9 Jan, 2013Your answer to Planetary Science: Why do some planets have an atmosphere while others don't?Added in Astronomy • 6 Jan, 2013Why do comets contain water?Followed in Astronomy • 30 Dec, 2012Assuming the Sun vanishes tomorrow, how can we survive without the Sun? What can we practically do?Followed in Astronomy • 29 Dec, 2012What happens when comets collide with each other?Added in Astronomy • 26 Dec, 2012What should everyone know about Betelgeuse?Added in Astronomy • 18 Dec, 2012NDSEG Fellowship: How can the military (and the Department of Defense) be interested in astronomy, exoplanets, and planetary atmospheres?Added in Astronomy • 11 Dec, 2012How does the Shannon information compare and contrast between main sequence stars, subgiant stars, giant stars, and supergiants?Added in Astronomy • 8 Dec, 2012What would be a rank-ordered list of the amount of Shannon information contained in each astronomical body in the solar system?Added in Astronomy • 8 Dec, 2012How much creep occurs on Uranus's moon Miranda?Added in Astronomy • 8 Dec, 2012What are the highest mountains on Titan?Added in Astronomy • 8 Dec, 2012How many comets and asteroids are there around T-Tauri stars?Added in Astronomy • 8 Dec, 2012What atmospheric waves were caused by the Tunguska meteor in 1908:?Added in Astronomy • 5 Dec, 2012What atmospheric waves were caused by the Tunguska meteor in 1908:?Added in Astronomy • 5 Dec, 2012What atmospheric waves were caused by the Tunguska meteor in 1908:?Added in Astronomy • 5 Dec, 2012What atmospheric waves were caused by the Tunguska meteor in 1908:?Added in Astronomy • 5 Dec, 2012Do significant meridional pole to equator temperature gradients exist on brown dwarfs?Added in Astronomy • 3 Dec, 2012Could Rigel or Deneb go supernova before Betelgeuse?Added in Astronomy • 3 Dec, 2012How can we modify the Earth's orbit so that it can collide with Mars?Added in Astronomy • 1 Dec, 2012Is it possible to destroy Jupiter's Red Spot?Added in Astronomy • 21 Nov, 2012Can Earth-based telescopes observe the Great White Spot on Saturn?Added in Astronomy • 27 Oct, 2012Do universities with strong planetary science departments often not even have astronomy departments?Added in Astronomy • 20 Oct, 2012How many people in deep earth processes are fundamentally interested in exoplanets?Added in Astronomy • 3 Oct, 2012How do I search for the content of specific NASA grants?Added in Astronomy • 3 Oct, 2012How helpful is a PhD in remote sensing helpful for the very long-term goal of finding habitable exoplanets?Added in Astronomy • 3 Oct, 2012If there are hypergiants and supergiants, why don't we have ultragiants?Added in Astronomy • 2 Aug, 2012What do astronomers and physicists think of each other?Added in Astronomy • 20 Jul, 2012Your answer to What's some shit that astronomers say?Added in Astronomy • 20 Jul, 2012If we use a probe to monitor the far side of the Sun, then can a probe on Mars or another planet possibly relay the information from the Sun's far side back to Earth?Added in Astronomy • 15 Jul, 2012Why doesn't the Great Red Spot on Jupiter migrate eastward or westward?Added in Astronomy • 10 Jul, 2012What's some stuff that astronomers like?Added in Astronomy • 6 Jul, 2012Is it possible to write a "fundamentals of physics" textbooks using examples derived *only* from astronomy?Added in Astronomy • 4 Jul, 2012What are some good ways to insult an astronomer?Added in Astronomy • 3 Jul, 2012What are some of the strongest schools for studying exoplanets?Added in Astronomy • 24 Jun, 2012Will Voyager 1 still collect any more interesting data once it's in interstellar space?Added in Astronomy • 16 Jun, 2012Is NASA more closely involved with earth/atmospheric science than with astronomy/astrophysics?Added in Astronomy • 4 Jun, 2012How common are Earth-sized rogue planets?Added in Astronomy • 24 May, 2012How much interplanetary dust leaves the solar system each year? And how much enters the solar system?Added in Astronomy • 24 May, 2012What caused the solar proton storm of January 2005?Added in Astronomy • 23 May, 2012Was it possible that the early Sun had superflares that could have affected the early Earth?Added in Astronomy • 23 May, 2012How do Astronomy PhD students usually learn their fluid dynamics?Added in Astronomy • 17 May, 2012Your answer to Astronomy: What determines the transit or directionality of a rogue planet?Added in Astronomy • 16 May, 2012What is it like to be a graduate student in Astronomy?Added in Astronomy • 10 May, 2012Why do coronal mass ejections have a positive pole and a negative pole?Added in Astronomy • 5 May, 2012What are coronal mass ejections like on other stars?Added in Astronomy • 5 May, 2012Your answer to Astronomy: Are there any known stars that aren't in a galaxy?Added in Astronomy • 5 May, 2012How would the Danjon scale apply to the eclipses of moons of other planets?Added in Astronomy • 4 May, 2012Have there been any studies done on eclipses that occur on non-Earth moons?Added in Astronomy • 4 May, 2012Your answer to Astronomy: Why are eclipses irregular?Added in Astronomy • 4 May, 2012What are some good ways to convince people to switch from math/physics/CS/EE over to Astronomy and Atmospheric Science?Added in Astronomy • 2 May, 2012Can increasing the amount of light that telescopes capture help us learn more about the physical processes that go on distant stars?Added in Astronomy • 23 Apr, 2012Can studying the variations in stellar output around other stars help us learn more about the variations in solar output around the Sun when the Sun was a younger star?Added in Astronomy • 10 Apr, 2012What subjects often form the butt of jokes made by astronomers?Added in Astronomy • 28 Mar, 2012What are some cultural faux pas that astrophysicists often make when interacting with earth and planetary scientists?Added in Astronomy • 12 Mar, 2012Is astronomy really separable from the geosciences?Added in Astronomy • 2 Mar, 2012How can society benefit from studying exoplanets?Added in Astronomy • 2 Feb, 2012Your answer to Does a bigger planet command bigger sized life forms? Or smaller ones?Added in Astronomy • 30 Jan, 2012How does the Harvard Smithsonian Center for Astrophysics compare and contrast with the Harvard Astronomy department?Added in Astronomy • 23 Jan, 2012How does someone remember the names of exoplanets?Added in Astronomy • 22 Jan, 2012What's some shit that astronomy majors say?Added in Astronomy • 20 Jan, 2012What's some shit that astronomers say?Added in Astronomy • 20 Jan, 2012What is the future of telescopes?Added in Astronomy • 20 Jan, 2012Can topology be applied to astronomy?Anonymous • Added in Astronomy • 19 Jan, 2012How can the study of exoplanets help inform the study of Earth?Anonymous • Added in Astronomy • 19 Jan, 2012Are circumbinary planets at greater risk from coronal mass ejections?Added in Astronomy • 19 Jan, 2012What could the Northern Lights presumably look like on an exoplanet?Added in Astronomy • 19 Jan, 2012How does magnetism affect how galaxies form?Added in Astronomy • 19 Jan, 2012Why does Stanford have no Astronomy department?Added in Astronomy • 18 Jan, 2012Your answer to Exoplanets: Is there a list of exoplanets?Added in Astronomy • 17 Jan, 2012Your answer to Jupiter (planet): What causes the bands in Jupiter's atmosphere and gives them their colours?Added in Astronomy • 17 Jan, 2012What are some ways that one can use gamification for astronomy education?Added in Astronomy • 15 Jan, 2012If a Hot Jupiter was not tidally locked, then are there any specific cases where its wind speeds would be milder than those found on Jupiter?Added in Astronomy • 12 Jan, 2012Is it feasible for an exoplanet to have moons with the mass of a Super-Earth? And how likely would it be?Added in Astronomy • 11 Jan, 2012Why do red dwarf/M-dwarf stars have unusually high levels of radiative output in the ultraviolet and X-ray range?Added in Astronomy • 8 Jan, 2012Do the astrobites.com authors read the entire paper before summarizing it?Added in Astronomy • 1 Jan, 2012Can solar winds affect earth's climate?Followed in Astronomy • 31 Dec, 2011Your answer to What operating systems do astronomers use?Added in Astronomy • 26 Dec, 2011Is it possible to watch the coronal mass ejections of a star outside the solar system?Added in Astronomy • 25 Dec, 2011Citizen Science: What is it like to participate in the crowdsourced Galaxy Zoo project?Added in Astronomy • 25 Dec, 2011What did the year 2011 bring to research in the intersection of exoplanetary atmospheres and astrobiology?Added in Astronomy • 25 Dec, 2011What are the top reasons why some people leave astronomy after graduate school?Added in Astronomy • 23 Dec, 2011Are there any robust features that are captured by the *parody* HR diagram for astronomers?Added in Astronomy • 20 Dec, 2011Why is outer space so capable of producing surreal images that no human could ever independently produce?Added in Astronomy • 17 Dec, 2011Your answer to Would the Earth absorb more energy if it were closer to the Sun?Added in Astronomy • 13 Dec, 2011Your answer to Is it possible that Mars used to be in the habitable zone when the Sun was hotter?Added in Astronomy • 13 Dec, 2011What are the downsides of being an astronomy grad student?Anonymous • Added in Astronomy • 11 Dec, 2011Could exoplanet art help inspire more interest in exoplanets?Added in Astronomy • 9 Dec, 2011Your answer to Which astronomical database is better, NED or SIMBAD?Added in Astronomy • 1 Dec, 2011Your answer to What is the farthest object from earth visible with the naked eye?Added in Astronomy • 1 Dec, 2011Was Carl Sagan more controversial within the Astronomy community or the Planetary Science one?Added in Astronomy • 1 Dec, 2011Your answer to Orbital Mechanics: How long until the moon is far enough from the Earth's gravitational field that it will no longer orbit the Earth?Added in Astronomy • 1 Dec, 2011Why do tidally locked planets have equatorial superrotation when many of the models predict that everything simply points to the center of the planet?Added in Astronomy • 30 Nov, 2011Your answer to What should the circumbinary planet discovered by the Kepler mission be named?Added in Astronomy • 30 Nov, 2011What is it like to go inside the Subaru Telescope?Added in Astronomy • 28 Nov, 2011What is it like to see Saturn through a telescope for the first time?Anonymous • Added in Astronomy • 27 Nov, 2011★What is it like to see Uranus through a telescope for the first time?Anonymous • Added in Astronomy • 27 Nov, 2011Your answer to Physics: Is there a program that can computationally fit spherical harmonic functions onto a dataset?Added in Astronomy • 24 Nov, 2011Your answer to Why are the rates of unemployment for graduating Astronomy/Astrophysics majors near zero percent?Added in Astronomy • 24 Nov, 2011Your answer to How hot is the sun in degrees Celsius?Added in Astronomy • 19 Nov, 2011Your answer to The Big Bang: What is cosmic background microwave radiation, and how does it support Big Bang theory?Anonymous • Added in Astronomy • 19 Nov, 2011Your answer to Why is Pluto no longer a planet?Added in Astronomy • 19 Nov, 2011Your answer to When will the Earth become uninhabitable to humans?Added in Astronomy • 19 Nov, 2011Your answer to Why is it important for a life harboring planet to have a magnetic field?Added in Astronomy • 19 Nov, 2011Your answer to Astronomy: What are stars made of?Added in Astronomy • 19 Nov, 2011Your answer to What existed before the Universe?Added in Astronomy • 17 Nov, 2011How likely is it that alpha, the electromagnetic constant, is actually variable like recent evidence has suggested?Followed in Astronomy • 6 Nov, 2011What do theoretical astrophysicists think of observational astronomers, planetary scientists, and astrobiologists?Added in Astronomy • 5 Nov, 2011What would happen if Jupiter collided with Saturn?Added in Astronomy • 4 Nov, 2011What causes the "sleepy" hollows on Mercury's surface?Added in Astronomy • 31 Oct, 2011How do you derive Avogadro's number from Rayleigh Scattering and the Sun?Followed in Astronomy • 29 Oct, 2011What is it like to major in astronomy?Added in Astronomy • 28 Oct, 2011Exoplanets: Couldn't we have crowdfunded the Space Interferometry mission?Added in Astronomy • 27 Oct, 2011Couldn't we have crowdfunded the Terrestrial Planet Finder mission?Added in Astronomy • 27 Oct, 2011Can we crowdfund an extension to the Kepler Mission?Added in Astronomy • 27 Oct, 2011Your answer to The Sun: How much sunlight hits the earth?Added in Astronomy • 27 Oct, 2011Your answer to Does fruit spoil in space?Added in Astronomy • 26 Oct, 2011Your answer to What is bigger, a universe or galaxy?Added in Astronomy • 23 Oct, 2011What is wrong with this exoplanet spectra?Anonymous • Added in Astronomy • 23 Oct, 2011When taking direct pictures of a star like Alpha Centauri A, how many pixels of the star can we capture with current technology?Added in Astronomy • 23 Oct, 2011Your answer to What is the surface of an asteroid like?Added in Astronomy • 23 Oct, 2011Why does astronomy have a higher female to male ratio than physics?Added in Astronomy • 21 Oct, 2011Your answer to Astronomy: What is the most beautiful astronomical object in the universe?Added in Astronomy • 19 Oct, 2011Your answer to Outer Space: What natural celestial objects are closest to being shaped like a cube?Added in Astronomy • 19 Oct, 2011How big would a sphere of water in space need to be before the pressure in the center from gravitational compression made interesting things happen? What might happen as a result?Followed in Astronomy • 14 Oct, 2011How would asteroid mining potentially work?Followed in Astronomy • 10 Oct, 2011What does it feel like to attend an American Astronomical Society conference?Added in Astronomy • 5 Oct, 2011Where can I learn more about a particular observed meteor?Followed in Astronomy • 3 Oct, 2011Can we use spectroscopy to detect snow/ice on exoplanets?Added in Astronomy • 29 Sep, 2011What are some common stereotypes of astronomy majors?Added in Astronomy • 26 Sep, 2011Your answer to Weather: What could be the consequences on the weather after a change in the Earth's axis?Added in Astronomy • 23 Sep, 2011Your answer to Astrophysics: If a planet identical to Earth were to appear on the opposite side of the sun, but in the same orbit, how long would the orbit stay stable, and would we be able to see it?Added in Astronomy • 23 Sep, 2011What percent of astronomy professors attend the AAS conference meetings each year?Added in Astronomy • 22 Sep, 2011What are the chances of actually producing results with GalaxyZoo research?Added in Astronomy • 18 Sep, 2011How often do people really needed to be reminded that light from a star 500 light-years away came 500 years ago?Added in Astronomy • 18 Sep, 2011How should we name new exoplanets?Added in Astronomy • 16 Sep, 2011What are some of the most interesting mysteries of space?Added in Astronomy • 12 Sep, 2011Which astronomy areas have the most low-hanging fruit for research?Added in Astronomy • 12 Sep, 2011Your answer to What are some explanations for the super-rotation of the upper layers of the atmospheres of Venus and Titan?Added in Astronomy • 7 Sep, 2011What are some explanations for the super-rotation of the upper layers of the atmospheres of Venus and Titan?Added in Astronomy • 7 Sep, 2011If we used the sidereal day, would we not need leap years?Added in Astronomy • 6 Sep, 2011Your answer to How many sister stars were born with our sun in its stellar nursery and how distant are they now?Added in Astronomy • 6 Sep, 2011Your answer to Are there certain alignments in the solar system's orbits that create additional interesting effects on our planets, moons, or sun?Added in Astronomy • 5 Sep, 2011Your answer to The Universe: Is the Universe compact?Added in Astronomy • 5 Sep, 2011Your answer to Why are astronomical events given such a high importance and reported in mainstream media ?Added in Astronomy • 2 Sep, 2011Your answer to Is every star in the night sky that is visible to the naked eye native to our galaxy?Added in Astronomy • 2 Sep, 2011Your answer to Do black holes collide?Added in Astronomy • 2 Sep, 2011Why is the moon a nearly perfect sphere?Anonymous • Added in Astronomy • 1 Sep, 2011Your answer to Astronomy: In older stars does fusion occur in each of the envelopes or just the core?Added in Astronomy • 31 Aug, 2011What is the type of music behind astronomical music? (like the music they use for planetariums)Added in Astronomy • 30 Aug, 2011What are some of the best astronomy/astrophysics videos on YouTube?Added in Astronomy • 29 Aug, 2011Your answer to Meteorites: In geological terms, how are meteorites classified?Added in Astronomy • 27 Aug, 2011What are the best graduate schools for studying astronomy/astrophysics?Added in Astronomy • 26 Aug, 2011Your answer to Why are many (revolving) structures in space mostly flat? Like galaxies, planetary orbits, or Saturn's rings.Added in Astronomy • 25 Aug, 2011What are some cultural faux pas in astronomy departments?Added in Astronomy • 24 Aug, 2011Your answer to Which universities have the most respected astrophysics/astronomy research programs?Added in Astronomy • 22 Aug, 2011Your answer to What is the difference between astronomy and cosmology?Added in Astronomy • 20 Aug, 2011Your answer to What is the orbital tilt angle of each of our solar system's planets with respect to the spin-axis of the Sun?Added in Astronomy • 20 Aug, 2011Is Sudarsky's system of extrasolar planet classification widely used? Why or why not?Added in Astronomy • 19 Aug, 2011Your answer to Does Mars or Earth have the biggest volcanoes?Added in Astronomy • 18 Aug, 2011Your answer to How do astrophysicists and astronomers measure astronomical distances?Added in Astronomy • 16 Aug, 2011Your answer to Why does the Earth-Moon distance increase?Added in Astronomy • 15 Aug, 2011Your answer to Astronomy: Why does our Moon move further from Earth as it's speeding up, but Phobos speeds up as it's moving closer to Mars?Added in Astronomy • 15 Aug, 2011Your answer to Why do cosmologists conclude that the universe is expanding faster and will expand forever?Added in Astronomy • 15 Aug, 2011Your answer to The Universe: Does the Universe have a center?Added in Astronomy • 15 Aug, 2011Your answer to How do astronomers map the universe?Added in Astronomy • 15 Aug, 2011Are there many mainstream physicists who are critical of the anthropic principle?Followed in Astronomy • 15 Aug, 2011Your answer to What is the average distance between stars throughout the galaxy and does the mean distance decrease towards the center of the galaxy?Added in Astronomy • 14 Aug, 2011Your answer to What are some good summer (or winter) programs/schools for graduate students in the earth/atmospheric/planetary sciences or in astrophysics?Added in Astronomy • 14 Aug, 2011What are some good summer (or winter) programs/schools for graduate students in the earth/atmospheric/planetary sciences or in astrophysics?Added in Astronomy • 14 Aug, 2011In geological terms, how are meteorites classified?Added in Astronomy • 11 Aug, 2011Is Galaxy Zoo an example of supervised learning?Added in Astronomy • 9 Aug, 2011Your answer to What are some good resources on astrobiology?Added in Astronomy • 28 Jul, 2011What are some good resources on astrobiology?Added in Astronomy • 28 Jul, 2011Your answer to How many scientists worldwide could be characterised as Mars specialists?Added in Astronomy • 27 Jul, 2011Your answer to What is the early Mars climate problem?Added in Astronomy • 27 Jul, 2011What is the current ratio of star birth to star death?Followed in Astronomy • 27 Jul, 2011Your answer to What's a quasar?Anonymous • Added in Astronomy • 24 Jul, 2011If the universe were contracting, could objects move toward each other at faster than the speed of light?Followed in Astronomy • 23 Jul, 2011Your answer to How is the age of a light wave coming from a distant object determined?Added in Astronomy • 23 Jul, 2011Your answer to Has the Earth's rotational period always been 24 hours? If not, what was it before, and what caused the change?Added in Astronomy • 22 Jul, 2011Your answer to Why does Pluto have so many satellites?Added in Astronomy • 20 Jul, 2011What are the most understudied areas in astrophysics?Added in Astronomy • 16 Jul, 2011Your answer to Why are the inner planets rocky and the middle planets large gas giants?Added in Astronomy • 15 Jul, 2011Why does terraforming still elude the grasp of modern science and technology?Followed in Astronomy • 15 Jul, 2011Do nearby gamma ray busts/supernova damage *more* than just the ozone layer?Added in Astronomy • 11 Jul, 2011Your answer to For how long has Jupiter's "great red spot" storm been going?Added in Astronomy • 9 Jul, 2011What are the best places in the US for stargazing?Followed in Astronomy • 9 Jul, 2011Your answer to Is there any clear evidence of what makes a gas giant's core?Added in Astronomy • 8 Jul, 2011Your answer to If a relatively small black hole were to appear in or near our solar system but not close enough to engulf any planets or the Sun, what would be the consequences?Added in Astronomy • 8 Jul, 2011Your answer to Could there be life in the Galactic Core?Added in Astronomy • 8 Jul, 2011Your answer to Space Exploration: Why do we remove spacecraft from orbit at the end of missions?Added in Astronomy • 8 Jul, 2011★If the government shuts down funding for the James Webb Space Telescope, then why can't we try private funding/crowdsourcing?Added in Astronomy • 6 Jul, 2011Are there any problems in astrophysics that would be solvable after the solar system makes half a revolution around the Milky Way? Would this also complicate future observations?Added in Astronomy • 4 Jul, 2011Your answer to Who was the first person in recorded history to document the possibility of life beyond earth?Added in Astronomy • 4 Jul, 2011How can one destroy the Sun?Followed in Astronomy • 2 Jul, 2011Your answer to If something died in outer space, would its body degenerate or float forever?Added in Astronomy • 30 Jun, 2011Your answer to Astrophysics: What are the most iconic images from astrophysics?Added in Astronomy • 30 Jun, 2011★What are the most iconic images from astrophysics?Added in Astronomy • 30 Jun, 2011Your answer to Is there any free planet formation and/or climate modeling modeling software available?Added in Astronomy • 28 Jun, 2011Your answer to How hard is the math if you major in astrophysics?Added in Astronomy • 27 Jun, 2011Your answer to What are some good websites and resources to learn about astronomy/astrophysics?Added in Astronomy • 25 Jun, 2011What are some good astronomy/astrophysics resources/tools?Added in Astronomy • 25 Jun, 2011★Will the rotations of a planet and its satellite "sync" after some time?Followed in Astronomy • 20 Jun, 2011Your answer to Why are most of the planets in the Solar System on nearly circular orbits?Added in Astronomy • 20 Jun, 2011Your answer to What's the average density of the Milky Way?Added in Astronomy • 20 Jun, 2011Your answer to What are the differences between a solar flare, a solar prominence, and a solar filament?Added in Astronomy • 20 Jun, 2011Your answer to Astronomy: What are the potential "profound implications" of the discovery that rogue/orphan planets may outnumber stars?Added in Astronomy • 20 Jun, 2011Your answer to What is Eddington luminosity?Added in Astronomy • 20 Jun, 2011Your answer to The Sun: What will happen if the Sun dies?Added in Astronomy • 20 Jun, 2011Your answer to Are there any astronomers who are also astrologists?Added in Astronomy • 20 Jun, 2011Your answer to If the The Big Bang theory is right, then why are some groups of galaxies supposedly older than the estimated age of The Universe itself?Added in Astronomy • 20 Jun, 2011Your answer to Will the closest star, Proxima Centauri come closer to Earth?Added in Astronomy • 20 Jun, 2011Your answer to In what order do all the astronomical catastrophes await us?Added in Astronomy • 20 Jun, 2011Your answer to Are there any other planets which also have an Ozone layer?Added in Astronomy • 20 Jun, 2011Your answer to Could the number of planets outnumber the number of stars?Added in Astronomy • 20 Jun, 2011Your answer to Can a planet still orbit (or hang on to) a hypervelocity star?Added in Astronomy • 20 Jun, 2011Your answer to Are there any practical uses for astrophysics?Added in Astronomy • 12 Jun, 2011Are there any practical uses for astrophysics?Added in Astronomy • 12 Jun, 2011Your answer to How do we find out how distant a star or a galaxy is?Added in Astronomy • 7 Jun, 2011Your answer to Earth: What would the climate be like on an earth-like planet with a 90-degree axial tilt?Added in Astronomy • 7 Jun, 2011If we found a habitable planet and wanted to colonize it, what would be the most feasible approach?Followed in Astronomy • 7 Jun, 2011If there is life on other planets, will it also be carbon based?Followed in Astronomy • 7 Jun, 2011Your answer to Is there a really good infographic explaining the big bang?Added in Astronomy • 6 Jun, 2011If you go into space, at what distance do you stop being "high" and start being "far away"?Followed in Astronomy • 10 May, 2011Your answer to Is there a correlation between the moon's distance from the earth, gravitational pull and earthquake activity?Added in Astronomy • 8 May, 2011What are the general differences in post-PhD research prospects for earth/atmospheric/planetary science PhDs as compared to astronomy PhDs?Added in Astronomy • 23 Apr, 2011Your answer to If I like the astronomy blog Dynamics of Cats, what other science blogs should I read?Added in Astronomy • 13 Apr, 2011What are the chances of catastrophic interaction with rogue planet in the Sun's lifetime?Added in Astronomy • 4 Apr, 2011How quickly did American researchers get data from Soviet probes like Venera?Added in Astronomy • 27 Mar, 2011Why is Earth not tidally locked to the Sun? Is distance a factor?Followed in Astronomy • 25 Mar, 2011Your answer to How can CS research, like computer vision research contribute to areas of Astronomy?Added in Astronomy • 19 Mar, 2011Is there a program that can computationally fit spherical harmonic functions onto a dataset?Added in Astronomy • 9 Mar, 2011Your answer to Astronomy: What are the heaviest elements made during stellar activity?Added in Astronomy • 6 Mar, 2011Your answer to How is the light from a red giant different from the light of our sun?Added in Astronomy • 6 Mar, 2011

1. The first armed drones were created to get Osama bin Laden.In 1998, U.S. President Bill Clinton’s administration shut down an operation to kill the al Qaeda leader in Afghanistan with cruise missiles, given collateral damage estimates of 300 casualties and only 50 percent confidence in the intelligence. As the 9/11 Commission noted, “After this episode Pentagon planners intensified efforts to find a more precise alternative.” In 2000 and 2001, the U.S. Air Force struggled to reconfigure a Hellfire anti-tank missile to fit onto a Predator surveillance drone. Meeting one week before the 9/11 attacks, the National Security Council agreed that the armed Predator was not ready to be operationally deployed. The first known killing by armed drones occurred in November 2001, when a Predator targeted Mohammed Atef, a top al Qaeda military commander, in Afghanistan.2. So far, drones tend to crash.On Dec. 4, an RQ-170 Sentinel surveillance drone crashed in Iran; a U.S. official involved in the program blamed a lost data link and another unspecific malfunction. Two weeks later, an unarmed Reaper drone crashed at the end of a runway in the Seychelles. “This should not be a surprise,” a defense official told Aviation Week & Space Technology, saying the United States had already lost more than 50 drones. As of July 2010, the Air Force had identified 79 drone accidents costing at least $1 million each. The primary reasons for the crashes: bad weather, loss or disruption of communications links, and “human error factors,” according to the Air Force. As Lt. Gen. David Deptula, former Air Force deputy chief of staff for intelligence, has noted with refreshing honesty, “Some of the [drones] that we have today, you put in a high-threat environment, and they’ll start falling from the sky like rain.”3. Drones are coming to America.Worried about the militarization of U.S. airspace by unmanned aerial vehicles? As of October, the Federal Aviation Administration (FAA) had reportedly issued 285 active certificates for 85 users, covering 82 drone types. The FAA has refused to say who received the clearances, but it was estimated over a year ago that 35 percent were held by the Pentagon, 11 percent by NASA, and 5 percent by the Department of Homeland Security (DHS). And it’s growing. U.S. Customs and Border Protection already operates eight Predator drones. Under pressure from the congressional Unmanned SystemsCacus — yes, there’s already a drone lobby, with 50 members — two additional Predators were sent to Texas in the fall, though a DHS official noted: “We didn’t ask for them.” Last June, a Predator drone intended to patrol the U.S.-Canada border helped locate three suspected cattle rustlers in North Dakota in what was the first reported use of a drone to arrest U.S. citizens.4. The scope of U.S. military drone missions is expanding…Drones have come a long way in little more than a decade of military use in strike operations. Five-pound backpack drones are now used by infantry soldiers for tactical surveillance and will soon be deployed for what their manufaturer calls “magic bullet” kamikaze missions. Special operations forces have developed a warhead fired from a Predator drone that can knock down doors. K-Max helicopter drones transport supplies to troops at forward operating bases in Afghanistan. Balloons unleash Tempest drones, which then send out smaller surveillance drones — called Cicadas — that glide to the ground to collect data. And now the U.S. State Department is flying a small fleet of surveillance drones over Iraq to protect the U.S. Embassy there. Bottom line: More and more drones have been rushed into service, and their use and application by the U.S. military is seemingly infinite.5. …But not as fast as civilian uses.Safety inspectors used drones at Japan’s crippled Fukushima Daiichi nuclear power plant to survey the damage after last year’s tsunami. Archaeologists in Russia are using small drones with infrared cameras to construct a 3-D model of ancient burial mounds. Environmental activists use the Osprey drone to track and monitor Japanese whaling ships. Photographers are developing a celebrity-seeking paparrazi drones. GALE drones will soon fly into hurricanes to more accurately monitor a storm’s strength. And Boeing engineers have joined forces with MIT students to build an iPhone app that can control a drone from up to 3,000 miles away. Last summer, using a laser 3-D printer, University of Southampton engineers built a nearly silent drone that can be assembled by hand in minutes.6. Most military drones don’t bomb.Although decapitation strikes may get all the headlines, the vast majority of the time, drones are used for intelligence, surveillance, and reconnaissance — what the military calls ISR. The U.S. Navy’s first high-altitude drone can relay black-and-white photos covering roughly half the Persian Gulf; the Global Hawk’s advanced radars make detailed images of the Earth and attempt to sniff out chemical or biological agents for telltale signs of weapons of mass destruction. Soon, the Gorgon Stare drone will “be looking at a whole city, so there will be no way for the adversary to know what we’re looking at, and we can see everything,” according to Maj. Gen. James O. Poss.7. Attack drones require more boots on the ground.Most unmanned aircraft flown by the U.S. military require not just a ground-based “pilot,” but also a platoon of surveillance analysts (approximately 19 per drone), sensor operators, and a maintenance crew. Some 168 people are required to keep a Predator drone aloft — and 180 for its larger cousin, the Reaper — compared with roughly 100 people for an F-16 fighter jet. To keep up with the demand, the Air Force has trained more drone operators than pilots for the past two years. The upside is that, according to the Congressional Budget Office, drones “are usually less expensive than manned aircraft” ($15 million for a Global Hawk versus about $55 million for a new F-16), though costly sensors and excessive crashes can negate the difference.8. Drones are becoming a lethal weapon of choice, but nobody’s in charge.Over the past decade, there have been some 300 drone strikes outside the battlefields of Iraq, Afghanistan, and Libya. Of these attacks, 95 percent occurred in Pakistan, with the rest in Yemen and Somalia; cumulatively, they have killed more than 2,000 suspected militants and an unknown number of civilians. Although U.S. President Barack Obama recently acknowledged that “a lot of these strikes” have been in Pakistan’s tribal areas, who can be targeted and under what authority can only be guessed from a few speeches and statements by anonymous U.S. officials. There are believed to be multiple drone-target “kill lists” among government agencies. The 2011 book Top Secret America revealed “three separate ‘kill lists’ of individuals” kept by the National Security Council, the CIA, and the military’s Joint Special Operations Command. In Yemen, the Pentagon is the lead executive authority for some drone strikes (which are reported to the congressional armed services committees), while the CIA is in charge for others (reported to the intelligence committees). As for the Obama administration’s claimed power to assassinate U.S. citizens, such as Yemeni-American cleric Anwar al-Awlaki, the Justice Department refuses to declassify the memo that provided the legal authority to kill him with a drone. So, although 85 percent of non-battlefield drone strikes have occurred under Obama, we have little understanding of their use.9. Other countries are catching up to the United States.As with most military programs, the United States is far and away the leader in developing drone technology, and the country is projected to account for 77 percent of drone R&D and 69 percent of procurement in the coming decade. Nevertheless, estimates of how many other countries have at least some drone capability now range from 44 to 70, for an estimated 680 drone programs around the world, up greatly from 195 in 2005. China is escalating its drone program, with at least 25 types of systems in development. Iran has also touted its program, including the armed “Ambassador of Death” drone, which President Mahmoud Ahmadinejad unveiled by declaring: “Its main message is peace and friendship.”10. The drone future is already here.The Pentagon now boasts a fleet of approximately 7,500 drones, up from just 50 a decade ago. According to a congressional report, “manned aircraft have gone from 95% of all [Defense Department] aircraft in 2005 to 69% today.” Over the next decade, the Pentagon expects the no of “multirole” drones — ones that can both spy and strike — to nearly quadruple, to 536. In 2011, the Teal Group consulting firm estimated that worldwide spending on unmanned aerial vehicles will nearly double over the next decade from $5.9 billion to $11.3 billion annually. In the future, drones are projected to: hover just behind infantry soldiers to watch their backs; carry airborne lasers to intercept ballistic missiles; perform aerial refueling; and conduct long-range strategic bombing missions. Given that drones will become cheaper, smaller, faster, stealthier, more lethal, and more autonomous, it is harder to imagine what they won’t do than what they will. Whatever limits drones face will be imposed by us humans — not technology.

Here is bibliographic data for Nature (academic journal) or Science Magazine papers published in 2004-2012 with Voyager 1 or Voyager 2 in the abstract, filtering out most of the Jupiter and Saturn papers.ÔªøFN Thomson Reuters Web of KnowledgeVR 1.0PT JAU Decker, Robert BKrimigis, Stamatios MRoelof, Edmond CHill, Matthew ETI No meridional plasma flow in the heliosheath transition region.SO NatureVL 489IS 7414BP 124EP 7DI 10.1038/nature11441PD 2012-Sep-6PY 2012AB Over a two-year period, Voyager 1 observed a gradual slowing-down ofradial plasma flow in the heliosheath to near-zero velocity after April2010 at a distance of 113.5 astronomical units from the Sun (1astronomical unit equals 1.5*10(8) kilometres). Voyager 1 was then about20 astronomical units beyond the shock that terminates the freeexpansion of the solar wind and was immersed in the heated non-thermalplasma region called the heliosheath. The expectation from contemporarysimulations was that the heliosheath plasma would be deflected fromradial flow to meridional flow (in solar heliospheric coordinates),which at Voyager1 would lie mainly on the (locally spherical) surfacecalled the heliopause. This surface is supposed to separate theheliosheath plasma, which is of solar origin, from the interstellarplasma, which is of local Galactic origin. In 2011, the Voyager projectbegan occasional temporary re-orientations of the spacecraft (totallingabout 10-25 hours every 2 months) to re-align the Low-Energy ChargedParticle instrument on board Voyager1 so that it could measuremeridional flow. Here we report that, contrary to expectations, theseobservations yielded a meridional flow velocity of +311kms(-1), that is,one consistent with zero within statistical uncertainties.TC 0ZB 0Z8 0Z9 0SN 1476-4687UT MEDLINE:22955623ERPT JAU Krimigis, Stamatios M.Roelof, Edmond C.Decker, Robert B.Hill, Matthew E.TI Zero outward flow velocity for plasma in a heliosheath transition layerSO NATUREVL 474IS 7351BP 359EP 361DI 10.1038/nature10115PD JUN 16 2011PY 2011AB Voyager 1 has been in the reservoir of energetic ions and electrons thatconstitutes the heliosheath since it crossed the solar wind terminationshock(1-3) on 16 December 2004 at a distance from the Sun of 94astronomical units (1 AU = 1.5 x 10(8) km). It is now similar to 22 AUpast the termination shock crossing(4). The bulk velocity of the plasmain the radial-transverse plane has been determined(5) using measurementsof the anisotropy of the convected energetic ion distribution(6). Herewe report that the radial component of the velocity has been decreasingalmost linearly over the past three years, from similar to 70 km s(-1)to similar to 0 km s(-1), where it has remained for the past eightmonths. It now seems that Voyager 1 has entered a finite transitionlayer of zero-radial-velocity plasma flow, indicating that thespacecraft may be close to the heliopause, the border between theheliosheath and the interstellar plasma. The existence of a flowtransition layer in the heliosheath contradicts currentpredictions(7)-generally assumed by conceptual models-of a sharpdiscontinuity at the heliopause.TC 12ZB 0Z8 0Z9 12SN 0028-0836UT WOS:000291647100041ERPT JAU Opher, M.Bibi, F. AlouaniToth, G.Richardson, J. D.Izmodenov, V. V.Gombosi, T. I.TI A strong, highly-tilted interstellar magnetic field near the SolarSystemSO NATUREVL 462IS 7276BP 1036EP 1038DI 10.1038/nature08567PD DEC 24 2009PY 2009AB Magnetic fields play an important (sometimes dominant) role in theevolution of gas clouds in the Galaxy, but the strength and orientationof the field in the interstellar medium near the heliosphere has beenpoorly constrained. Previous estimates of the field strength range from1.8-2.5 mu G and the field was thought to be parallel to the Galacticplane(1) or inclined by 38-60 degrees (ref. 2) or 60-90 degrees (ref. 3)to this plane. These estimates relied either on indirect observationalinferences or modelling in which the interstellar neutral hydrogen wasnot taken into account. Here we report measurements of the deflection ofthe solar wind plasma flows in the heliosheath(4) to determine themagnetic field strength and orientation in the interstellar medium. Wefind that the field strength in the local interstellar medium is 3.7-5.5mu G. The field is tilted similar to 20-30 degrees from the interstellarmedium flow direction (resulting from the peculiar motion of the Sun inthe Galaxy) and is at an angle of about 30 degrees from the Galacticplane. We conclude that the interstellar medium field is turbulent orhas a distortion in the solar vicinity.TC 23ZB 0Z8 0Z9 23SN 0028-0836UT WOS:000272996000042ERPT JAU McComas, D. J.Allegrini, F.Bochsler, P.Bzowski, M.Christian, E. R.Crew, G. B.DeMajistre, R.Fahr, H.Fichtner, H.Frisch, P. C.Funsten, H. O.Fuselier, S. A.Gloeckler, G.Gruntman, M.Heerikhuisen, J.Izmodenov, V.Janzen, P.Knappenberger, P.Krimigis, S.Kucharek, H.Lee, M.Livadiotis, G.Livi, S.MacDowall, R. J.Mitchell, D.Moebius, E.Moore, T.Pogorelov, N. V.Reisenfeld, D.Roelof, E.Saul, L.Schwadron, N. A.Valek, P. W.Vanderspek, R.Wurz, P.Zank, G. P.TI Global Observations of the Interstellar Interaction from theInterstellar Boundary Explorer (IBEX)SO SCIENCEVL 326IS 5955BP 959EP 962DI 10.1126/science.1180906PD NOV 13 2009PY 2009AB The Sun moves through the local interstellar medium, continuouslyemitting ionized, supersonic solar wind plasma and carving out a cavityin interstellar space called the heliosphere. The recently launchedInterstellar Boundary Explorer (IBEX) spacecraft has completed its firstall-sky maps of the interstellar interaction at the edge of theheliosphere by imaging energetic neutral atoms (ENAs) emanating fromthis region. We found a bright ribbon of ENA emission, unpredicted byprior models or theories, that may be ordered by the local interstellarmagnetic field interacting with the heliosphere. This ribbon issuperposed on globally distributed flux variations ordered by both thesolar wind structure and the direction of motion through theinterstellar medium. Our results indicate that the external galacticenvironment strongly imprints the heliosphere.TC 96ZB 0Z8 0Z9 96SN 0036-8075UT WOS:000271712300028ERPT JAU Schwadron, N. A.Bzowski, M.Crew, G. B.Gruntman, M.Fahr, H.Fichtner, H.Frisch, P. C.Funsten, H. O.Fuselier, S.Heerikhuisen, J.Izmodenov, V.Kucharek, H.Lee, M.Livadiotis, G.McComas, D. J.Moebius, E.Moore, T.Mukherjee, J.Pogorelov, N. V.Prested, C.Reisenfeld, D.Roelof, E.Zank, G. P.TI Comparison of Interstellar Boundary Explorer Observations with 3D GlobalHeliospheric ModelsSO SCIENCEVL 326IS 5955BP 966EP 968DI 10.1126/science.1180986PD NOV 13 2009PY 2009AB Simulations of energetic neutral atom (ENA) maps predict flux magnitudesthat are, in some cases, similar to those observed by the InterstellarBoundary Explorer ( IBEX) spacecraft, but they miss the ribbon. Ourmodel of the heliosphere indicates that the local interstellar medium(LISM) magnetic field (B(LISM)) is transverse to the line of sight (LOS)along the ribbon, suggesting that the ribbon may carry its imprint. Theforce-per-unit area on the heliopause from field line draping and theLISM ram pressure is comparable with the ribbon pressure if the LOSsimilar to 30 to 60 astronomical units and B(LISM) similar to 2.5microgauss. Although various models have advantages in accounting forsome of the observations, no model can explain all the dominantfeatures, which probably requires a substantial change in ourunderstanding of the processes that shape our heliosphere.TC 57ZB 0Z8 0Z9 57SN 0036-8075UT WOS:000271712300031ERPT JAU Richardson, John D.Kasper, Justin C.Wang, ChiBelcher, John W.Lazarus, Alan J.TI Cool heliosheath plasma and deceleration of the upstream solar wind atthe termination shockSO NATUREVL 454IS 7200BP 63EP 66DI 10.1038/nature07024PD JUL 3 2008PY 2008AB The solar wind blows outward from the Sun and forms a bubble of solarmaterial in the interstellar medium. The termination shock occurs wherethe solar wind changes from being supersonic ( with respect to thesurrounding interstellar medium) to being subsonic. The shock wascrossed by Voyager 1 at a heliocentric radius of 94 AU ( 1 AU is theEarth - Sun distance) in December 2004 ( refs 1 - 3). The Voyager 2plasma experiment observed a decrease in solar wind speed commencing onabout 9 June 2007, which culminated in several crossings of thetermination shock between 30 August and 1 September 2007 ( refs 4 - 7).Since then, Voyager 2 has remained in the heliosheath, the region ofshocked solar wind. Here we report observations of plasma at and nearthe termination shock and in the heliosheath. The heliosphere isasymmetric, pushed inward in the Voyager 2 direction relative to theVoyager 1 direction. The termination shock is a weak, quasi-perpendicular shock that heats the thermal plasma very little. Anunexpected finding is that the flow is still supersonic with respect tothe thermal ions downstream of the termination shock. Most of the solarwind energy is transferred to the pickup ions or other energeticparticles both upstream of and at the termination shock.TC 135ZB 0Z8 0Z9 135SN 0028-0836UT WOS:000257308300035ERPT JAU Decker, R. B.Krimigis, S. M.Roelof, E. C.Hill, M. E.Armstrong, T. P.Gloeckler, G.Hamilton, D. C.Lanzerotti, L. J.TI Mediation of the solar wind termination shock by non-thermal ionsSO NATUREVL 454IS 7200BP 67EP 70DI 10.1038/nature07030PD JUL 3 2008PY 2008AB Broad regions on both sides of the solar wind termination shock arepopulated by high intensities of non- thermal ions and electrons. Thepre- shock particles in the solar wind have been measured by thespacecraft Voyager 1 ( refs 1 - 5) and Voyager 2 ( refs 3, 6). The post-shock particles in the heliosheath have also been measured by Voyager 1( refs 3 - 5). It was not clear, however, what effect these particlesmight have on the physics of the shock transition until Voyager 2crossed the shock on 31 August - 1 September 2007 ( refs 7 - 9). UnlikeVoyager 1, Voyager 2 is making plasma measurements(7). Data from theplasma(7) and magnetic field(8) instruments on Voyager 2 indicate thatnon- thermal ion distributions probably have key roles in mediatingdynamical processes at the termination shock and in the heliosheath.Here we report that intensities of low- energy ions measured by Voyager2 produce non- thermal partial ion pressures in the heliosheath that arecomparable to ( or exceed) both the thermal plasma pressures and thescalar magnetic field pressures. We conclude that these ions are the>0.028 MeV portion of the non- thermal ion distribution that determinesthe termination shock structure(8) and the acceleration of whichextracts a large fraction of bulk- flow kinetic energy from the incidentsolar wind(7).TC 84ZB 0Z8 0Z9 84SN 0028-0836UT WOS:000257308300036ERPT JAU Stone, Edward C.Cummings, Alan C.McDonald, Frank B.Heikkila, Bryant C.Lal, NandWebber, William R.TI An asymmetric solar wind termination shockSO NATUREVL 454IS 7200BP 71EP 74DI 10.1038/nature07022PD JUL 3 2008PY 2008AB Voyager 2 crossed the solar wind termination shock at 83.7 AU in thesouthern hemisphere, 10 AU closer to the Sun than found by Voyager 1 inthe north(1-4). This asymmetry could indicate an asymmetric pressurefrom an interstellar magnetic field(5,6), from transient-induced shockmotion(7), or from the solar wind dynamic pressure. Here we report thatthe intensity of 4 - 5 MeV protons accelerated by the shock near Voyager2 was three times that observed concurrently by Voyager 1, indicatingdifferences in the shock at the two locations. ( Companion papers reporton the plasma(8), magnetic field(9), plasma- wave(10) and lower energyparticle(11) observations at the shock.) Voyager 2 did not find thesource of anomalous cosmic rays at the shock, suggesting that the sourceis elsewhere on the shock(12-14) or in the heliosheath(15-19). The smallintensity gradient of Galactic cosmic ray helium indicates that eitherthe gradient is further out in the heliosheath(20) or the localinterstellar Galactic cosmic ray intensity is lower than expected(21).TC 129ZB 1Z8 0Z9 129SN 0028-0836UT WOS:000257308300037ERPT JAU Burlaga, L. F.Ness, N. F.Acuna, M. H.Lepping, R. P.Connerney, J. E. P.Richardson, J. D.TI Magnetic fields at the solar wind termination shockSO NATUREVL 454IS 7200BP 75EP 77DI 10.1038/nature07029PD JUL 3 2008PY 2008AB A transition between the supersonic solar wind and the subsonicheliosheath was observed by Voyager 1, but the expected terminationshock was not seen owing to a gap in the telemetry(1-4). Here we reportobservations of the magnetic field structure and dynamics of thetermination shock, made by Voyager 2 on 31 August - 1 September 2007 ata distance of 83.7 AU from the Sun ( 1 AU is the Earth - Sun distance).A single crossing of the shock was expected, with a boundary that wasstable on a timescale of several days. But the data reveal a complex,rippled, quasi- perpendicular supercritical magnetohydrodynamic shock ofmoderate strength undergoing reformation on a scale of a few hours. Theobserved structure suggests the importance of ionized interstellar atomsshock.TC 81ZB 0Z8 0Z9 81SN 0028-0836UT WOS:000257308300038ERPT JAU Gurnett, D. A.Kurth, W. S.TI Intense plasma waves at and near the solar wind termination shockSO NATUREVL 454IS 7200BP 78EP 80DI 10.1038/nature07023PD JUL 3 2008PY 2008AB Plasma waves are a characteristic feature of shocks in plasmas, and areproduced by non- thermal particle distributions that develop in theshock transition layer. The electric fields of these waves have a keyrole in dissipating energy in the shock and driving the particledistributions back towards thermal equilibrium(1). Here we report thedetection of intense plasma- wave electric fields at the solar windtermination shock. The observations were obtained from the plasma- waveinstrument on the Voyager 2 spacecraft(2). The first evidence of theapproach to the shock was the detection of upstream electron plasmaoscillations on 1 August 2007 at a heliocentric radial distance of 83.4AU ( 1 AU is the Earth - Sun distance). These narrowband oscillationscontinued intermittently for about a month until, starting on 31 August2007 and ending on 1 September 2007, a series of intense bursts ofbroadband electrostatic waves signalled a series of crossings of thetermination shock at a heliocentric radial distance of 83.7 AU. Thespectrum of these waves is quantitatively similar to those observed atbow shocks upstream of Jupiter, Saturn, Uranus and Neptune.TC 20ZB 0Z8 0Z9 20SN 0028-0836UT WOS:000257308300039ERPT JAU Wang, LinghuaLin, Robert P.Larson, Davin E.Luhmann, Janet G.TI Domination of heliosheath pressure by shock-accelerated pickup ions fromobservations of neutral atomsSO NATUREVL 454IS 7200BP 81EP 83DI 10.1038/nature07068PD JUL 3 2008PY 2008AB The solar wind blows an immense magnetic bubble, the heliosphere, in thelocal interstellar medium ( mostly neutral gas) flowing by the Sun(1).Recent measurements by Voyager 2 across the termination shock, where thesolar wind is slowed to subsonic speeds before entering the heliosheath,found that the shocked solar wind plasma(2) contains only similar to 20per cent of the energy released by the termination shock, whereasenergetic particles(3) above similar to 28 keV contain only similar to10 per cent; similar to 70 per cent of the energy is unaccounted for,leading to speculation(2,3) that the unmeasured pickup ions or energeticparticles below similar to 28 keV contain the missing energy. Here wereport the detection and mapping of heliosheath energetic ( 4 - 20 keV)neutral atoms produced by charge exchange of suprathermal ions withinterstellar neutral atoms. The energetic neutral atoms come from asource similar to 60 degrees wide in longitude straddling the directionof the local interstellar medium. Their energy spectra resemble those ofsolar wind pickup ions, but with a knee at similar to 11 keV instead ofsimilar to 4 keV, indicating that their parent ions are pickup ionsenergized by the termination shock. These termination- shock- energizedpickup ions contain the missing similar to 70 per cent of the energydissipated in the termination shock, and they dominate the pressure inthe heliosheath.TC 12ZB 0Z8 0Z9 12SN 0028-0836UT WOS:000257308300040ERPT JAU Opher, M.Stone, E. C.Gombosi, T. I.TI The orientation of the local interstellar magnetic fieldSO SCIENCEVL 316IS 5826BP 875EP 878DI 10.1126/science.1139480PD MAY 11 2007PY 2007AB The orientation of the local interstellar magnetic field introducesasymmetries in the heliosphere that affect the location of heliosphericradio emissions and the streaming direction of ions from the terminationshock of the solar wind. We combined observations of radio emissions andenergetic particle streaming with extensive three-dimensionalmagnetohydrodynamic computer simulations of magnetic field draping overthe heliopause to show that the plane of the local interstellar field issimilar to 60 degrees to 90 degrees from the galactic plane. Thisfinding suggests that the field orientation in the Local InterstellarCloud differs from that of a larger-scale interstellar magnetic fieldthought to parallel the galactic plane.TC 50ZB 0Z8 0Z9 50SN 0036-8075UT WOS:000246369800033ERPT JAU Giampieri, GDougherty, MKSmith, EJRussell, CTTI A regular period for Saturn's magnetic field that may track its internalrotationSO NATUREVL 441IS 7089BP 62EP 64DI 10.1038/nature04750PD MAY 4 2006PY 2006AB The rotation rate of a planet is one of its fundamental properties.Saturn's rotation, however, is difficult to determine because there isno solid surface from which to time it, and the alternative 'clock'-themagnetic field-is nearly symmetrically aligned with the rotationaxis(1-7). Radio emissions, thought to provide a proxy measure of therotation of the magnetic field, have yielded estimates of the rotationperiod between 10 h 39 min 22 s and 10 h 45 min 45 s (refs 8-10).Because the period determined from radio measurements exhibits largetime variations, even on time-scales of months, it has been uncertainwhether the radio-emission periodicity coincides with the inner rotationrate of the planet. Here we report magnetic field measurements thatrevealed a time-stationary magnetic signal with a period of 10 h 47 min6 s +/-40 s. The signal appears to be stable in period, amplitude andphase over 14 months of observations, pointing to a close connectionwith the conductive region inside the planet, although itsinterpretation as the 'true' inner rotation period is still uncertain.TC 64ZB 1Z8 0Z9 64SN 0028-0836UT WOS:000237248600031ERPT JAU Fisk, LATI Journey into the unknown beyondSO SCIENCEVL 309IS 5743BP 2016EP 2017DI 10.1126/science.1118762PD SEP 23 2005PY 2005AB The Voyager 1 spacecraft has passed an important milestone. As isreported in papers in this issue, Voyager 1 has crossed the terminationshock of the solar wind, where the wind abruptly decelerates to beginits merger into the local interstellar medium. The termination shockprovided surprises; the region beyond is truly uncharted territory.TC 18ZB 0Z8 0Z9 18SN 0036-8075UT WOS:000232181900037ERPT JAU Stone, ECCummings, ACMcDonald, FBHeikkila, BCLal, NWebber, WRTI Voyager 1 explores the termination shock region and the heliosheathbeyondSO SCIENCEVL 309IS 5743BP 2017EP 2020DI 10.1126/science.1117684PD SEP 23 2005PY 2005AB Voyager 1 crossed the termination shock of the supersonic flow of thesolar wind on 16 December 2004 at a distance of 94.01 astronomical unitsfrom the Sun, becoming the first spacecraft to begin exploring theheliosheath, the outermost layer of the heliosphere. The shock is asteady source of low-energy protons with an energy spectrum similar toE-1.41 +/- 0.15 from 0.5 to similar to 3.5 megaelectron volts,consistent with a weak termination shock having a solar wind velocityjump ratio r = 2.6(-0.2)(+0.4). However, in contradiction to manypredictions, the intensity of anomalous cosmic ray (ACR) helium did notpeak at the shock, indicating that the ACR source is not in the shockregion local to Voyager 1. The intensities of similar to 10-megaelectronvolt electrons, ACRs, and galactic cosmic rays have steadily increasedsince late 2004 as the effects of solar modulation have decreased.TC 282ZB 2Z8 0Z9 282SN 0036-8075UT WOS:000232181900038ERPT JAU Decker, RBKrimigis, SMRoelof, ECHill, MEArmstrong, TPGloeckler, GHamilton, DCLanzerotti, LJTI Voyager 1 in the foreshock, termination shock, and heliosheathSO SCIENCEVL 309IS 5743BP 2020EP 2024DI 10.1126/science.1117569PD SEP 23 2005PY 2005AB Voyager 1 (V1) began measuring precursor energetic ions and electronsfrom the heliospheric termination shock (TS) in July 2002. During theensuing 2.5 years, average particle intensities rose as V1 penetrateddeeper into the energetic particle foreshock of the TS. Throughout 2004,V1 observed even larger, fluctuating intensities of ions from 40kiloetectron volts (keV) to >= 50 megaelectron volts per nucleon and ofelectrons from >26 keV to >= 350 keV. On day 350 of 2004 (2004/350), V1observed an intensity spike of ions and electrons that was followed by asustained factor of 10 increase at the lowest energies and lesserincreases at higher energies, larger than any intensities since V1 wasat 15 astronomical units in 1982. The estimated solar wind radial flowspeed was positive.(outward) at similar to +100 kilometers per second(km s(-1)) from 2004/352 until 2005/018, when the radial flows becamepredominantly negative (sunward) and fluctuated between similar to -50and 0 km s(-1) until about 005/110; they then became more positive, withrecent values (2005/179) of similar to +50 km s(-1). The energeticproton spectrum averaged over the postshock period is apparentlydominated by strongly heated interstellar pickup ions. We interpretthese observations as evidence that V1 was crossed by the TS on 2004/351(during a tracking gap) at 94.0 astronomical units, evidently as theshock was moving radially inward in response to decreasing solar windram pressure, and that V1 has remained in the heliosheath until at leastmid-2005.TC 206ZB 1Z8 0Z9 206SN 0036-8075UT WOS:000232181900039ERPT JAU Gurnett, DAKurth, WSTI Electron plasma oscillations upstream of the solar wind terminationshockSO SCIENCEVL 309IS 5743BP 2025EP 2027DI 10.1126/science.1117425PD SEP 23 2005PY 2005AB Electron plasma oscillations have been detected upstream of the solarwind termination shock by the plasma wave instrument on the Voyager 1spacecraft. These waves were first observed on 11 February 2004, at aheliocentric radial distance of 91.0 astronomical units, and continuedsporadically with a gradually increasing occurrence rate for nearly ayear. The last event occurred on 15 December 2004, at 94.1 astronomicalunits, just before the spacecraft crossed the termination shock. Sincethen, no further electron plasma oscillations have been observed,consistent with the spacecraft having crossed the termination shock intothe heliosheath.TC 50ZB 0Z8 0Z9 50SN 0036-8075UT WOS:000232181900040ERPT JAU Burlaga, LFNess, NFAcuna, IHAcuna, MHLepping, RPConnerney, JEPStone, ECMcDonald, FBTI Crossing the termination shock into the hetiosheath: Magnetic fieldsSO SCIENCEVL 309IS 5743BP 2027EP 2029DI 10.1126/science.1117542PD SEP 23 2005PY 2005AB Magnetic fields measured by Voyager 1 show that the spacecraft crossedor was crossed by the termination shock on about 16 December 2004 at94.0 astronomical units. An estimate of the compression ratio of themagnetic field strength B (+/- standard error of the mean) across theshock is B-2/B-1 = 3.05 +/- 0.04, but ratios in the range from 2 to 4are admissible. The average B in the heliosheath from day 1 through day110 of 2005 was 0.136 +/- 0.035 nanoteslas, similar to 4.2 times thatpredicted by Parker's model for B. The magnetic field in the heliosheathfrom day 361 of 2004 through day 110 of 2005 was pointing away from theSun along the Parker spiral. The probability distribution of hourlyaverages of B in the heliosheath is a Gaussian distribution. The cosmicray intensity increased when B was relatively large in the hetiosheath.TC 145ZB 0Z8 0Z9 145SN 0036-8075UT WOS:000232181900041ERPT JAU Kerr, RATI Planetary science - Voyager 1 crosses a new frontier and may save itselffrom terminationSO SCIENCEVL 308IS 5726BP 1237EP 1238PD MAY 27 2005PY 2005TC 3ZB 0Z8 0Z9 3SN 0036-8075UT WOS:000229482300005ERPT JAU Reichhardt, TTI NASA's funding shortfall means journey's end for Voyager probesSO NATUREVL 434IS 7030BP 125EP 125DI 10.1038/434125aPD MAR 10 2005PY 2005TC 0ZB 0Z8 0Z9 0SN 0028-0836UT WOS:000227494500003ERPT JAU Sanchez-Lavega, ATI Viewpoint - How long is the day on Saturn?SO SCIENCEVL 307IS 5713BP 1223EP 1224DI 10.1126/science.1104956PD FEB 25 2005PY 2005AB Determining a planet's rotation period can be difficult if the planettacks a solid surface. However, for planets with an internal magneticfield, emissions at radio wavelengths are modulated by the planet'srotation rate. The latest results from the Cassini spacecraft seem toindicate that Saturn's rotation rate has slowed down by 6 minutes sincethe Voyager 1 and 2 spacecraft flew by the planet in 1980 and 1981, butit is unclear whether a slowdown has in fact occurred. Future datacollected by Cassini may be able to resolve the question.TC 21ZB 0Z8 0Z9 21SN 0036-8075UT WOS:000227313200036ERPT JAU Prange, RPallier, LHansen, KCHoward, RVourlidas, ACourtin, GParkinson, CTI An interplanetary shock traced by planetary auroral storms from the Sunto SaturnSO NATUREVL 432IS 7013BP 78EP 81DI 10.1038/nature02986PD NOV 4 2004PY 2004AB A relationship between solar activity and aurorae on Earth waspostulated(1,2) long before space probes directly detected plasmapropagating outwards from the Sun(3). Violent solar eruption eventstrigger interplanetary shocks(4) that compress Earth's magnetosphere,leading to increased energetic particle precipitation into theionosphere and subsequent auroral storms(5,6). Monitoring shocks is nowpart of the 'Space Weather' forecast programme aimed at predictingsolar-activity-related environmental hazards. The outer planets alsoexperience aurorae, and here we report the discovery of a strongtransient polar emission on Saturn, tentatively attributed to thepassage of an interplanetary shock - and ultimately to a series of solarcoronal mass ejection (CME) events. We could trace the shock-triggeredevents from Earth, where auroral storms were recorded, to Jupiter, wherethe auroral activity was strongly enhanced, and to Saturn, where itactivated the unusual polar source. This establishes that shocks retaintheir properties and their ability to trigger planetary auroral activitythoughout the Solar System. Our results also reveal differences in theplanetary auroral responses on the passing shock, especially in theirlatitudinal and local time dependences.TC 40ZB 0Z8 0Z9 40SN 0028-0836UT WOS:000224854900041EREF