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 What would a toroidal planet be like?
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Undergrad Why there is so little carbon in Earth crust?
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Graduate Question about the expansion of the universe:
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Graduate Big Bang Origins: "Nothing" of Physics vs. Philosophy
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Undergrad What Causes Elliptical Galaxies to be Elliptical?
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Graduate Planetary Formation Based on Matter Condensation and Accretion
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Undergrad Is the Universe Expanding or Has it Already Expanded?
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Graduate Can torsion avoid the big bang singularity
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Undergrad Universe expansion beyond c at some distant point?
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Undergrad Gravity & Shapes: Ellipse, Parabola, Hyperbola?
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Undergrad Can you reach absolute zero in complete empty space
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Undergrad Redshift & Far Distant Stars: Effects on Temperature
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Undergrad Importance of a standard candle?
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Undergrad Measuring the distance to stars using parallax
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Undergrad Quick question about negative declinations
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Undergrad Maintaining orbit around the moon
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Graduate Perpetual acceleration of the universe expansion?
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Graduate Million Kelvin gas clouds? Really?
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Graduate How Does Gravity Balance Forces Without Mass in a Pre-Big Bang Energy Scenario?
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Graduate Formula for the star density of the milky way?
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Graduate Mechanism for generating the energy in supernova
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High School Has Andromeda Moved Closer in 2.5 Million Years?
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Graduate Why would gravity slow down the Universe's expansion?
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Undergrad No Earth, No Gravity: What Would it Be?
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On which altitude does the heaven turns in black?
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Undergrad How can knowing parallax of a farther object help with finding a nearer object?
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Undergrad Milkyway Black-hole vs Andromeda Collision
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Graduate Quasar Turn On z<1 Quasar Clustering
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Graduate Most logical answer for the universe
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Graduate Flat Universe, dark energy and accelerating expansion
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Graduate Help: Explaining Expanding/Accelerating Universe Without Redshift Fallacy
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Graduate Can the Multiverse Expand Without a Realm to Expand Into?
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High School Astrophysics Prerequisites Question
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Graduate Largest Structure in Universe: 4B Light-Years Long LQG
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Graduate Question about gravity on the large scale.
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Graduate Thought this would be interesting - largest structure in Universe Discovered
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Undergrad Did Astronauts Face Dangerous Radiation During Apollo Missions?
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Graduate Unveiling the Mystery of Dark Matter: A Comprehensive Lecture on DM
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Stargazing Celestron UpClose Porro Series 10-30 x 50 Zoom Binoculars
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Undergrad Is KOI 172.02 the Most Earth-Like Exoplanet Discovered?
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Graduate Is the Local Fluff Causing Warming in Our Solar System?
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Undergrad What is the Solar Constant in the Kuiper Belt?
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Graduate Accelerating Universal Expansion
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Undergrad The lost energy of Cosmic Background Radiation
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Graduate Velocity Dispersion Questions - Shounak
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Graduate How can we reconcile the paradox of seeing the Big Bang?
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Graduate Does an Infinite Universe Challenge the Laws of Thermodynamics?
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Undergrad What is the Role of Earth's Axis in Copernican Astronomy?
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Graduate The significance of the existence of the universe
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Graduate Dwarf Galaxies Orbiting the Andromeda Galaxy unexplained by Dark matter
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Graduate Could pre-big-bang evidence survive the crunch?
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High School Unraveling the Mystery of Sagittarius A and A*
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Graduate Projected Separation and 3D Distance Problem (Code Included)
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Graduate Similarities of negative absolute temperature to dark energy?
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Graduate Role of Strong Force in Neutron Stars
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Graduate What's the Deal with Astrophysical Jets?
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Graduate Relativistic at freeze out? Definition of HDM
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Undergrad Exoplanet Maps: Northern and Southern Hemisphere Locations
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High School Does the Milky Way Orbit Anything? Investigating Our Galaxy's Center
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Graduate Does dark matter act as a medium for sound to go through?
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Undergrad How does Angular Momentum relate to the rapid rotation of Pulsars?
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Undergrad Stars heat up when they lose energy
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Undergrad The equilibrium in the universe ?
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Graduate Exploring Beyond Absolute Zero: Thermodynamics Re-examined
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Undergrad How Does Gravitational Lensing Bend Light in Space?
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Undergrad Black Holes: Mass, Schwarzschild Radius & Size
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Graduate Alpher Bethe Gamow: Factor characterizing the decrease of density with time
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High School The Universe. Orderly, Chaotic, or some of both?
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Undergrad Is it possible at all to go faster in an orbit around the earth?
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Undergrad Calculate Mass of Moon from Earth & Diameter
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Graduate Some questions for want of answers:
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Graduate How do we determine the production of H and He during BBN?
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Graduate Planck Intermediate Results. IX. Detection of the Galactic haze with Planck
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Graduate Distribution of stars by Metallicity and Redshift
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Stargazing Zhumell Z12 vs Meade Light Bridge 10
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Can the moon be viewed an night at the same time from two positions 77deg apart
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Undergrad Which mathematical formulas are used in the search for extraterrestrial planets?
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Graduate SPT-SZ Survey Results: New Neutrino Species Suggested
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Graduate Cannot stand the eternity in cyclic models
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Graduate Can Black Holes Be Used for Faster-Than-Light Travel?
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High School Earth revolves in eliptical path?
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Undergrad Launching an object into OUTER space
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Graduate Mass distribution and gravitational field
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High School Entropy: Definition, Explanation & Meaning
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Graduate Integrating Friedmann Equation of Multi-component universe respect to a and t
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Undergrad How Do You Choose What Scientific Papers to Read?
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Graduate Higher sensitivity CMB mapper (EBEX) launched
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Graduate Can We Determine the Center of the Universe Using Comet Orbits?
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Graduate Question involving space travel and the expansion of the universe
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Graduate Unraveling the Mystery of the Universe's Origin
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High School Sun's path in the sky during Equinox if watching from equator?
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Graduate Time Before Big Bang: Stephen Hawking & Other Universes
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Graduate Explaining the Virial Theorem in Astrophysics
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Undergrad How will the pattern of stars in the milky way change over time?
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Graduate Black holes: Some astronomers detected flashes of x-ray in the cosmos
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Graduate Faber-Jackson Relation: Explained | Shounak
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Graduate Why do smaller black holes emit more Hawking radiation?
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Graduate Was Energy in the Expanding Universe Traveling at the Speed of Light?
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Graduate What Exists Beyond the Reach of the First Photon in the Universe?
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Undergrad Dark Matter and Dark Energy: WTH are they?
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