Astronomy, Astrophysics, Cosmology Forum

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Join in expert discussion on the topics of Astronomy, astrophysics and cosmology. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Undergrad White Dwarfs,Black Dwarfs & neutron star
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Graduate The 'fermi Line' (the 130 GEv gamma ray signal)
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Graduate How orbiting bodies arrange themselves in orbital resonance?
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Graduate Questions on the Inflation Debate
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Graduate Is the universe expanding or it is circuiting?
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Graduate Black Hole Radiation: Stephen Hawking's Theory Explained
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Graduate The size of the universe at the big bang?
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Graduate Singularity and size of universe
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Graduate Big Bang Matter-Antimatter Annihilation
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Graduate Inconsequence in Lawrence Krauss lecture
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High School Intuitively - why aren't black holes hot?
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High School Please, help with observation plan
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Undergrad What is different in Solar Radio vs Radio Flux 10.7 cm?
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Undergrad Is there some liquid planets out there?
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Graduate No Inflation in Brane Cosmology: Is Dark Energy the Driver?
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Graduate Where Can I Find Reliable Information on Dark Flow?
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Undergrad Active Galaxies and the Unified Model
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Graduate Classsification of Pre main sequence(PMS) stars
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Graduate Unleashing the Power of the Universe: The Mystery of Universal Energy
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Undergrad Are static models totally static?
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Graduate Where does dark energy come from
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Undergrad Low and high orbital energy differences (getting there and back)
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Undergrad Discovering the True Speed of Light: A Question on Its Absolute Nature
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High School Why Is the Solar System Structured the Way It Is?
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High School Where can I find a downloadable database of stars?
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Graduate Luminosity Distance, Determination From Type Ia SN
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How Can One Reach Outside of Time and Space?
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High School What Existed Before the Big Bang?
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Graduate Location of Earth in the Universe
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Graduate Confusion about redshift in a universe with accelerating expansion
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Undergrad Is light pollution causing wasted energy and costing billions of dollars?
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Undergrad What Is It Like at the Edge of the Universe?
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Graduate Deuterons used up before reaching the A=5 and 8 bottlenecks?
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High School General question, where can I learn about all the constellations and
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Graduate Hey, I was reading Neil Turok's book (The Universe Within) and it got
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Stargazing Telescope Resolving Power Limits
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Graduate Does Photon Emission Influence Celestial Body Movement?
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Graduate Can We Move in Planck Length and Dimension at the Time of the Big Bang?
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Graduate New hab-zone planet HD40307g distance 42 ly, estim 7 earthmass
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Graduate Is There a 100 Solar Mass Black Hole in Orion Nebula?
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Graduate What is the nature of matter and its relation to eternity?
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Graduate Help understanding solar imaging wavelength and coronal temp
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Graduate Z ~ 11 galaxy observed by CLASH most distant as of Nov 2012
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Undergrad Is Space Considered a Medium for Photons and Other Waves?
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Graduate Quasar Mass-Luminosity, High Mass Turnoff Evolution and a Synchronization Puzzle
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High School What is the Definition of Space in Physics?
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Undergrad Big Bang Singularity: What is it?
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High School Method for spaceship to be absolutely still in space
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Undergrad Orphan planets, i.e., planets not in a solar system
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Undergrad Is a Webcam Better than a DSLR for Astrophotography?
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Undergrad Searching for Colliding Stars: Has the Phenomena Ever Been Observed?
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Adjective term of pertaining to a non-Earth moon
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Graduate Is spacetime not the same as space and time ?
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Graduate If doppler shift can be caused by gravity
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Graduate Is the Universe Truly Infinite and Ever-Expanding?
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Undergrad Will Earth pass through the galactic plane in 2012?
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Graduate Since the Sun is losing mass, can a planet's orbit change be measured?
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Graduate Observable universe and events between vast distances
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Graduate Understanding Jeans Instability & Masses
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Undergrad You always hear people say that the universe is made of matter and energy
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Graduate Measuring the Distance Between First & Last Particles of the Big Bang
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Undergrad Need Help Understanding Angular Resolution
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Graduate Longitude of the Ascending nodes (calculation, wrong data perhaps?)
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Graduate Inverse square law resolves Olbers' paradox
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Graduate Recent papers relevant to cosmology that seemed extra interesting
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High School Since the earth orbits in an ellipse, not a circle
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Graduate What Is the Nature of the Space Left Behind After the Big Bang?
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Undergrad Does Dark Energy Repel Light and Cause Damage?
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Graduate An amusing paper about the size of the Universe
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Undergrad Can Black Holes Bend Time?
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Graduate Does time run fast near universe's edge?
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Stargazing 60-80 mm refracting telescope for beginners
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Graduate Correct interpretation of terms in proper velocity expression?
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High School Gravitational Constant: Questions and Ideas
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Undergrad How does momentum dumping work on the Hubble Space Telescope?
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Graduate Can a Spacecraft Achieve Light Speed Using Jupiter's Magnetic Field?
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Graduate What is the Color of a Neutron Star?
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Stargazing How do radio telescopes form images?
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Graduate Measurment that proves that the universe is flat
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Undergrad How to convert flux from counts to erg.
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Graduate Expansion of Universe but no expansion of galaxies
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Graduate Are there non-spherical blackholes?
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Stargazing World’s largest Cherenkov telescope opens
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Graduate Is the speed of light constant for a co-moving observer?
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Graduate Are rays from opposite sides of a hot spot of CMB parallel or not?
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Undergrad Urban Space Saving: Reducing Traffic with Raised Roadways and Shops
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High School Does the Earth actually revolve around the Sun
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Graduate Heat of the Big Bang: Understanding CMB & Accuracy
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Graduate Is age of universe adjusted for gravity?
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Undergrad Can Amateur Telescopes Detect Exoplanets?
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High School Planet Found Orbiting Alpha Centauri
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Graduate Does energy dilate time like mass?
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Graduate Problem interpreting Mpc/h in maps of DM
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Undergrad Just how dark is Pluto from orbit? How about Saturn?
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Undergrad Position and angle of Earth/Moon/Sun and timing
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High School Can I see stars through the moon?
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Undergrad Could Ice Form Inside the Sun?
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Undergrad What is the Scientific Understanding of Gravity?
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Interesting simulation of a spiral galaxy evolution.
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Undergrad What Determines the Diameter of a Moon Halo?
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