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.
Graduate Gravitational attraction between two atoms
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Graduate Evidence that time and space began at the instant of the big
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Graduate Star post-main sequence timescale
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Graduate Test set-up for full dark matter simulation
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Is Stacking RAW Images the Key to High-Quality Astrophotography?
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Graduate Does the Expansion of the Universe Affect Thermal Equilibrium?
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Undergrad Venus Transit - What should be a simple problem
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High School Need to exchange a helical focuser for a rack and pinion one
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High School How large an area is that brightly illuminted patch from stars covering?
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Graduate Properties of an evolved universe
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Graduate Could energy be extracted from spacetime expansion?
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Graduate Can the CMB Reference Frame be Changed in the Newtonian Friedmann Equation?
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Graduate 814 Ghostly Galaxies in the Coma Cluster
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Graduate Radiation dominated universe in Newton's approximation (no )
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Graduate Inflation & Pertubative 1st order Cosmology: A timeline?
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Graduate Age of universe -- Probability why it is so young?
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High School Will the Voyager Golden Records withstand the harshness of space?
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Graduate Does the Equation 1=Ω_k+Ω_m+Ω_Λ Hold for All Universe Types?
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Graduate Chemical potential equilibrium cosmology
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Graduate White Dwarfs Catalogue - Find Mass & Radius Data
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Graduate Hubble redshift and calculation of galactic rotation curves
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Graduate Early Universe Black Holes: A Challenge to Standard LCDM?
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Graduate Adiabatic perturbations -- why the name?
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Graduate Why Does Everything in the Universe Rotate?
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Graduate Integrated Boltzman equation for dark matter
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Graduate Recent Early Universe Cosmology Review - Funding Essay
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Graduate Interpretting the cosmological constant
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Graduate The impossible early galaxy formation
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Undergrad Pluto's moon Nix and its wild tumbling orbit
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Graduate Does universe expansion create new points in space?
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Undergrad Will future stars create new elements through evolution?
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Graduate Massive primordial tensor perturbations?
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Undergrad Discover Earth's Plasma Rings | Cleo Loi Proves Existence of Plasma Tubes
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Graduate Understanding Solar UV Radiation and Its Impact on Earth: A Brief Overview
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Graduate Functional dependence of the size of the visible universe
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Graduate Are Primordial Black Holes Still a Viable Candidate for Dark Matter?
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Undergrad Is it theoretically possible for a star to orbit a planet?
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Stargazing Reflector telescope, what to do?
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Graduate Is Deja Vu the Brain's misinterpretation of Spacetime?
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Undergrad Milky Way Mass: 60,000 Ly from Galactic Center
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Graduate Debunking the Mathematical Proof Against the Big Bang Theory
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Undergrad Number of Particles in Universe: Protons, Neutrons, Electrons
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I just saw a fireball and nobody cares
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Undergrad Does Inflation Refer to the Expansion of Space or the Entire Universe?
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Graduate Does Isotropy Necessarily Imply Homogeneity in the Universe?
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Graduate Star Nuclear Reaction: P+P, D+P, He3 and CNO Cycle
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Undergrad Why do small bodies stay in orbit around large bodies?
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Graduate Sky temperature profiles and black body radiation
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Graduate Emergence of much smaller stars in early Universe?
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Graduate Where Does the 10^-35 s^-2 Cosmological Constant Value Come From?
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Graduate Excluding the Standard Model from Dark Matter?
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Graduate Article with good analysis of different models?
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Graduate Did a Giant Impact Make the Martian Moons?
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Graduate Is There Evidence of a Type Ia Supernova Formed via the Single Degenerate Mode?
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Graduate A Question about the formation of white holes off black hole
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Graduate What is the limit of classical GR in describing the singularity of a black hole?
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Undergrad Is the Density of Points in an Interval Twice as Much with Double Length?
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Undergrad Understanding the Units of Permittivity of Free Space in Coulomb's Law
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Graduate How Do Direct Collapse Black Holes Form in the Early Universe?
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Undergrad Are Asteroids Formed by Collisions or Accretion?
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Graduate Where Can I Access a Database for Universe Mass Distribution and Movement?
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Graduate CMB photons, why are they still around?
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Graduate Where do things go after they were sucked by a Blackhole?
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Micrometeorite caught on camera in Oklahoma?
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Graduate Sagittarius A*: the riddle of gas cloud G2
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Graduate Ceres/Mars as manufacturing outposts (analytic exercise)
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Graduate How to calculate the Age of the Universe, from observations
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High School Is This Picture Really About the CNO Cycle?
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Graduate Is Matter/Energy Eternal? Mechanisms for an Endless Universe?
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Can You Spot All the Galaxies in This Virgo Supercluster Photo?
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Graduate Trajectory opimization: Fast preview algorithm
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Undergrad Can Kepler's 2nd Law be applied to more than one planet?
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Graduate Other evidences of the Galaxys' Acceleration
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Graduate What does it mean by a flat universe?
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Undergrad Question about Kepler's 1st law and barycentric orbits
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Graduate Can We Harness Black Holes for Faster Flybys?
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Graduate Four random quasars in a straight line?
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Graduate When can globular clusters be considered collisionless?
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Graduate Distances for classical objects vs. photons
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Graduate Can you have an antimatter black hole?
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Graduate Just for fun: recast the Friedmann eqn. to be about volume instead
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A&C Reference Library - Astronomy & Cosmology Resources
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High School Are Galaxies in Hubble Telescope Photos of Clusters?
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Graduate Can Anti Matter Galaxies and Black Holes Exist Together?
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Graduate Center of mass - cant find error in derivation
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Graduate Questions on the Lyman Alpha Profile
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Undergrad Can light pressure affect the motion of galaxies?
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Graduate Do clocks measure conformal time?
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High School Is Time an Illusion? A 13-Year-Old's Take on the Block Universe Concept
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Graduate Conformal symmetry of FRW spacetime
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Undergrad Calculating an Escape from Earth's Gravity: Can It Be Done?
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Graduate Intuition Behind Scale Invariance Power Spectrum
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Graduate Penrose's cyclic universe - question
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Graduate Why isn't everything expanding in an expanding universe?
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Insights Animating Black holes and Singularities - Comments
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Graduate Killing vectors and momentum conservation
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Undergrad Does the Universe Have its Own Clock and Period?
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High School Proof that the moon is closer to Earth than the sun
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Undergrad Could you send an object into space completely without fuel?
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High School Discover the Fascinating Rotations of the Moon | Gibraltar to Auckland Views
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