Astronomy and Astrophysics Forum

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Join in expert discussion on the topics of Astronomy and astrophysics. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Graduate Would a single black hole form in the big crunch scenario?
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Undergrad All stars in Milky Way equal one square light year?
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High School What Pope wanted Galileo to include in his book
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High School How Does Sunlight Reach the Moon During a Full Moon?
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Undergrad Is Empty Space Truly Void of Energy and Matter?
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Undergrad Doppler effect vs expansion effect on wavelength
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High School Questions About Things in Orbit and Why They Don't Descend
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Graduate Synchronization of time impossible?
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Undergrad Kepler's 2nd.law and calculation
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Graduate First detection of pop III stars?
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Graduate Titan's atmosphere vs temperature.
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Undergrad Calculating HZ for Contact Binary Systems
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Undergrad How Large Can a Planet be and Still Have Earth's Mass?
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Undergrad Satellites in various orbits above the earth exploded?
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Graduate What is Plasma-Fire and Why is it So Dangerous?
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Graduate Mass: Accretion Disk vs. Black Hole
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Undergrad Deteriorating Orbits of Satellites and Objects
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Undergrad Planetary Composition: Elements Beyond Silicon, Iron & Carbon
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What is the bright, changing light in the southwestern sky in France?
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Undergrad Unraveling the Mysteries of Speed: From Particles to Galaxies
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Graduate Could life arise on a brown dwarf?
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High School Enormous alien planet discovered
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High School What would happen to a human body exposed to space without a spacesuit?
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Are there road traffic rules in Space?
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Graduate What is the largest reflection angle in the Chandra X-ray telescope?
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Undergrad How Does the Oberth Effect Work?
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Graduate Meta Materials as Cosmic Ray Shielding for Spacecraft?
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Undergrad Is constant planetary alignment (syzygy) possible ?
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High School Understanding Planet Orbits & Revolutions Around the Sun
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Graduate Earth's Atmosphere Without Magnetic Field & Geology
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High School Why Sun Rays Lose Heat in Space: Examining the Unknown
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Graduate Maximum velocity of ISON and some other stuff
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Undergrad How do Planets generate electromagnetic waves?
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Stargazing Will the James Webb telescope see past the big bang?
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Graduate Is There a Different Event Horizon for Dark Matter?
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Undergrad Does the center of the galaxy intersect the ecliptic?
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Graduate Evidence of Orbiting Black Holes?
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Graduate Why is there any residual angular momentum left over from the big bang
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Graduate Prevalence of Earth-size planets orbiting Sun-like stars
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Undergrad Solar eclipse - magnitude and albedo
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Anybody here keeping track of ison
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High School Time lapse image of Comet ISON, what looks like snow?
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Graduate How Do You Calculate Delta V in a 1-D Gravitational Field?
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Undergrad Can a Running Tap Water Basin Be an Analogy for a Black Hole Event Horizon?
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Graduate Is the Quantum Vacuum in Deep Space the Same as on Earth?
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Graduate Gamma Ray Burst GRB 130427A: The Brightest Explosion in the Universe
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Graduate Where Does Gravity Get Its Energy From?
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Graduate Hawking radiation and its significance
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Graduate What was the primordial composition of U isotopes in solar system?
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Undergrad Gravity, center of planets, stars
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Undergrad Cygnus X1: Date of Highest Excursion
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High School Are We Discovering New Stars in the Observable Universe?
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High School Can a Planet Collect Enough Mass to Become a Black Hole?
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Graduate Is the universe really expanding?
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Graduate How Are Heavy Nuclei Produced in Black Hole Jets?
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Undergrad Calculating Apparent Magnitude of The Moon
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Undergrad Space Cold: Is a Vacuum of Space Really Cold?
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Undergrad Earth's shadow in the atmosphere
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Graduate Orbit of figure eight 3 or more bodies
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Graduate Could black holes be empty points of spinning systems? A scientific exploration
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Graduate How do we know blackholes are dense? Could instead they be a vortex?
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Graduate Tidal forces,moons & changing orbit in solar system.
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Hyperbolic Comet C-2012 S1 (ISON)
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Undergrad Why are Black Holes such massive gravity pools?
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Graduate Star formation activity and SMBH activity
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Graduate How does this relate to the size and mass of gas giants like Kepler 7b?
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High School Layperson's question regarding earth's rotational wobble
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Graduate Mass loss in relation to radius of a star
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Undergrad Why does the sun's heat & light intensity decrease over AU distances?
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Undergrad Dimensions - how many are there in universe?
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Graduate Is Motion Possible in a Continuous Space?
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Graduate Calculating physical separation of 2 sources at unknown angle.
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Graduate Hells Angels bikie in a Beijing Opera Concert
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Graduate Could WIMPs Interact to Form Dark Planets and Stars?
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Graduate Calculating Consistency of a Point Mass System w/ Dark Matter
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That galaxy at the end of 'Empire Strikes Back'
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High School Silly Question Re Distance and Time
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Graduate The paradox of Hawking radiation - is matter infinitely compressible?
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Undergrad How does jupiter's moon get so hot?
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Graduate Question on Gravity, Big Bang, Dark Energy and Black Holes
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Website For Universe map, and Matter Totals
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Graduate Estimate the number of stars with present-day luminosity function
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High School Is it possible for the earth to come off orbit and crash into the sun?
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Undergrad Radiated Energy from the Sun: Is It Diminishing?
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Odd Body in Asteroid Belt with 6 Tails
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Undergrad Forgotten force: The other great cosmic attractor
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Finding an Astronomer for Your Fictional Galaxy: Tips and Tricks
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Graduate Giant monopoles as a dark matter candidate
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Graduate Can electric fields/currents be seen on the sun?
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Graduate Can neutrinos travel faster than light?
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Graduate What's on the other side of a black hole?
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Graduate Conceptual problem on black hole singularity
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Undergrad How Many Universes Exist in the Multiverse?
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Graduate What is the estimated mass flow in relativistic jets from black holes?
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Undergrad Calculating Mass Lost of Iron Asteroid Hitting Earth
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Graduate How to Calculate the Lower Limit of the Diameter of an Icy Minor Planet?
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Undergrad How long do you expect transit to last?
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Graduate Pulsar Orbiting another body, doppler shifted pulse rate problem
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Graduate Flywheel inside a spaceship experiment
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Undergrad Achievable orbit from launch location
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