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 The Effect of Planets Rotation within its Galaxy?
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Undergrad Questions about the structure of the universe
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Undergrad Astronomy Resources for Learning & Research
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Russia plans to leave International Space Station
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Graduate Andromeda vs Milky Way dust emissions
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Graduate Initial conditions for tensor perturbations
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Graduate The application of of Fermi Dirac statistics in the white dwarf
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Graduate Gravity causing distances smaller than a Plack length?
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Graduate Data on the Velocity of the Celestial Bodies Orbiting a Galaxy
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Graduate Holographic principle in reverse
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Undergrad How was the core temperature of sun estimated ?
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Graduate Several questions regarding the nature of the universe
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Undergrad Galactic Habitable Zone Theory: A Physiologist's Inquiry
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Graduate Can the Boltzmann equation accurately predict the relic density of dark matter?
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Graduate Dark Energy/Matter: Why Does It Make Sense?
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Name Exoplanets: IAU Plans to Name 305 Exoplanets
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Graduate Is there a "missing light crisis"?
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Graduate Traveling to Andromeda in 2 Months with a Spaceship
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Graduate Is Redshift Only a Result of Universal Expansion?
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Graduate Conversion between density and column density
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High School Do Objects in Space Float or Maintain a Fixed Position?
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Undergrad Stopping a star from going supernova
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Graduate Lay-ish approach to *both* Friedman equations (2nd try)
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Undergrad Could we read a newspaper from a satellite image?
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Graduate A speculative explanation why universe accelerates
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Graduate Is There a Maximum Distance Limit in Our Universe?
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Graduate Chandrashekhar paper on white dwarf
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Graduate Questioning 3D Model views of effect of large bodies on curving space.
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Graduate Chandrashekhar limit for relativistic fermion gas
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Graduate How Do You Evaluate a Line of Sight Integral for Dark Matter Annihilation?
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Graduate Passing of time in Bolzmann's entropy curve. Is it all wrong?
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Undergrad Why can we see light emitted near the beginning of the universe?
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Graduate Expansion, redshift, and conservation of energy
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Start planting trees on mars now
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Graduate Does the Existence of the Axis of Evil Mean a Special Frame of Reference?
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Graduate Light Cone - Hubble Radius & Time T and R Relationship
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Graduate What is "empty space" composed of?
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Graduate Problem in Dodelson Modern Cosmology
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Graduate What Triggers a Supernova Explosion During a Star's Core Collapse?
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Graduate Big Dipper Cosmic Ray Hotspot Homogeneity question
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Graduate Solar System destroyed vs Supernova
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Graduate Momentum transfer when object falls into black hole
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Is Intelligent Life in the Universe a Waste of Space?
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Graduate Why Do Io and Titan Exhibit Unique Surface Phenomena?
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Graduate CMB cold spot explanation proposed (looks good)
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Graduate Were the first stars much larger and shorter-lived than our sun?
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Graduate Expansion of Space vs Velocity in Space
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Graduate FRW cosmology [itex]Ω_{Λ}[/itex] domination
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Undergrad Are We Also Expanding with the Universe?
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Moon occultation of Mars tonight
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Graduate Why the Universe is accelerating as it is expanding
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Graduate How many infinite universes can fit within a multiverse?
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Undergrad Hubble Finds Vast Reservoir of Gas Near Milky Way
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Undergrad What is the basis of Rotation Curve?
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Undergrad Understanding and Creating an O-C Diagram
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Graduate Cosmology, Quantum fluctuations,and entanglement
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Undergrad Is There a Simple Equation for Hubble's Constant and Time in Astronomy?
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Graduate Why does A black hole need a massive center
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Graduate Are Wormholes Really Impossible Without Exotic Matter?
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Undergrad Why didn't the big bang just become a black hole?
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Graduate Calculating the Density and Volume of Matter in the Expanding Universe
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Graduate Decoupling condition for dark matter WIMP
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High School Battery in Space? Current Flow in Vacuum?
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Graduate Chronology of recessional velocity
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Undergrad Can the Sun's size affect the orbits of planets around it?
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Graduate Why should the universe succumb to our measurments
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Graduate Infinite Universe: What does it mean?
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Vale Bill Bradfield - The loss of a comet hunter
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Graduate Trio of Big Black Holes Found in Galaxy Smashup
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Graduate Discovering the Oldest and Most Distant Star: HD140283 Subgiant Star
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Graduate Dark Energy: A Total Nuisance to Physicists?
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Graduate Reason the early Universe was opaque?
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Graduate The Probability of an Infinite Universe
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Graduate Size of Universe at CMB last Scattering
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Graduate Acceleration of Universe: Friedmann Equations
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Graduate Proof of/Reason for SVT Decomposition
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Undergrad Why do most galaxies have a flat, disc-like shape?
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Undergrad Large Body Orbiting a Small One?
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Does anyone know which paper that this figure come from?
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Graduate Boundaries of Time in The Evolution of The Universe
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Graduate Does the Block Universe Theory Suggest Time and Motion Are Illusions?
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Graduate What is the relationship between the Hubble radius and the age of the universe?
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Graduate How Can the Big Bang Occur Without Time?
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Graduate Boltzmann equation for photons
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Graduate Discover the Relationship Between CMB's Temperature and Redshift z in Cosmology
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Graduate Was the expansion of the universe always greater than c?
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Graduate Scalar field in Expanding Universe EOM
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Graduate Couldn't the universe be finite if Omega =1?
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Graduate Ratio of matter to radiation density
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Undergrad Will the Universe Shrink and Reignite Life?
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Graduate Is dimensionless singularity truly dimensionless?
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High School Structure of galaxy and the laws behind it
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High School Earth as a Capacitor: Lightning & Rain
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Graduate Interaction of three black holes
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Undergrad Can Black Holes Be Broken Apart?
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Undergrad Radio Waves from Stars: Investigating the Mysteries
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Undergrad Where Do Electrons Go in the Plasma State of Stars?
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Graduate Is Dark Energy Actually the Pull of Black Holes?
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Graduate Did Matter Exist Before Time? - Hartle-Hawking State
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Graduate Properties of Matter in Vacuum (Space)
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