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.
Gigantic Full Worm Moon this Weekend
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Undergrad Reasonable mass and surface gravity of fictional planet based on radius
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High School High School Debate topic: Space development and Exploration
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Graduate How can hawking radiation escape?
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Graduate Universe - bubbles of Dark Matter?
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Graduate Exploring the Lambda Constant and the Big Bang Theory
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Graduate The Grand Speculation - Investigating Hawking's Theory
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Undergrad Jovian Moons: Is a Small Jovian a Moon of a Larger One?
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Undergrad When the sun becomes a black dwarf
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Graduate Do wormholes allow for time travel and travel to other dimensions?
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Graduate What Happens if a Scale Model of the Sun Weighs as Much as the Real Sun?
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High School Debunking Equinox Myths: Balancing Silver Dollars and Eggs on the Vernal Equinox
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Graduate What is the color of a neutron star?
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High School Positioning of the artificial satellite
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Graduate Is Energy Truly Conserved in an Expanding Universe?
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Undergrad Space saver compartments with mechanical crank device
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Undergrad Doppler Shift at Right Angles Confusion
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Graduate Variable light speed and speical relativity
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Graduate Calculating the Hubble Constant at Different Redshifts
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Graduate Naked singularities and traversable wormholes
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High School Travel in Space: Electric or Fuel?
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Uranus’ atmosphere – creative help
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Graduate Is the fate of black dwarfs to become neutron stars without proton decay?
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High School EDIT: Guys I just need someone to take me under their wing for a
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Size comparison, from the moon to the largest known star
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Graduate Evidence for spatial variantion of the fine structure constant
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Undergrad How did the planets acquire their spin?
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Graduate Dark Energy: Mass, Distance & Gravity Relationships
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Graduate Questions About Time Before the Big Bang
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Graduate Is my analysis of star observations in Orion accurate?
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Graduate Does the Big Bang Theory Contradict the First Law of Thermodynamics?
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Undergrad Understanding Retrograde Orbit: Velocity Requirements for Artificial Satellites
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Graduate Pulsating variable star mathematics question
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Graduate Spherical star in a hydrostatic equilibrium
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Undergrad Velocity of a star for Doppler Spectroscopy
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Graduate The degree of order in the Universe
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Graduate Coliding Galaxies: A Highly Ordered Event?
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Discover Gliese 581g - Just 20 Light-Years Away!
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Graduate How did the big bang ever stop being a black hole?
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Graduate Puzzle of scalar dynamic in the early universe
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High School What would happen if the Earth become completely solid?
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Graduate Gravitational Speed: Is Removal & Creation Equal?
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Graduate Calculating Moon's Total Kinetic Energy
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Graduate What is the meaning of expansion in Loop Quantum Cosmology?
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High School Are Private Companies the Key to the Future of Outer Space Exploration?
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Graduate Measuring Distances Across Billions of Light Years
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Graduate Dark Energy Theory Gets Boost From New Measurements
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Graduate Simulating Galactic Evolution in a Game
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Graduate Getting the hubble constant from time delay in a gravitational lens
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1st law of thermodynamics & a theist
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Graduate Initial state of the Universe (order or chaos)
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High School Movement of spaceships versus spacewalkers
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Graduate Is a Constant Velocity Dispersion a Solution to the Jeans Equations of Galaxy?
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Graduate Travel from one spacetime to another?
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Japan's Seismic Activity Altered the Earth's Axis
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Did the Sun Go Dark Last Night?
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Graduate Looking for defunct papers/theories
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Graduate Requirements for Light Speed Travel (as we understand now)
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Graduate What happens to mass when it approaches the speed of light?
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Graduate Why Is There More Matter Than Antimatter in the Universe?
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Graduate What Energy Sources Could Sustain a Refuge in an Expanding Universe?
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Undergrad A manned mission to Mars and its obstacles
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Graduate Does the Event Horizon of a Black Hole Only Form on the Equitorial Plane?
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Undergrad Red Giant: The Death of a Star & Its Expansion
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Undergrad What happens to entropy in a cyclical universe?
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Graduate Could All Matter Be Curved Space Itself?
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Graduate How does the 'atmosphere' of the sun affect ligth from stars passing behind it.
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High School Position of stellar bodies in space.
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Graduate Summer Solstice Prediction: Effects of Phase Shift Parameters & Assumptions
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Undergrad Could the Big Bang really have happened in an instant?
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Undergrad Is space made up of individual units?
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Graduate Can a Maximally Rotating Black Hole be Defined by the Kerr Metric?
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Undergrad How Does the Gravitational Slingshot Effect Propel Objects?
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Undergrad What is the connection between antimatter and dark matter?
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Graduate The eccentricity of binary stars' orbits
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Graduate Total radiation flux from a star
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Graduate Cyclic Universe, Big Rip version
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Undergrad Do Wormholes Exist in Our Universe or Just in Apples?
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Graduate What is the critical density of the Universe using hubble's constant?
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Graduate How is Hubble's equations H(t) = 2/3 t^-1 derived?
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Undergrad Can galaxies separate at speeds faster than the speed of light?
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Graduate What is the definition of adiabatic CMb spectrum in simple inflationary models?
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Graduate Are Event Horizons Different for Quantum and Supermassive Black Holes?
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Graduate Doesn't the big bang model rule out an infinite universe?
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Graduate What Happens Inside a Black Hole Beyond the Event Horizon?
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Graduate All forces neuralized at big bang, & space expansion
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Undergrad Universe Expansion: Is a Big Crunch Imminent?
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Last chance to see Discovery in orbit
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Undergrad Gravitational Force: Why is Normal to Path of Satellites, Planets?
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Graduate CMB Power spectrum/CMB anisotropies -> Geometry of Universe
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Graduate Maximum value of Hubble parameter (near start of expansion)
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Graduate What Are the Mysteries of Black Holes and Their Impact on Time and Motion?
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Graduate How do you explain the CMB anisotropy diagram?
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Graduate Exploring Long-Range Coulomb Interactions in Space
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Graduate How is the observed redshift caused by a recessional velocity?
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Graduate Book about Measurements in Astronomy and Cosmology
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Undergrad Earth's position relative to the Sun.
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Graduate Substellar temperatures comparable to that of the Earth
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Graduate Source of energy for white dwarf and neutron star
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Graduate Hawking radiation from a black hole?
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