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 Is all the space there is here now or is space being created
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High School Can We Use Silicon Oxide Bags to Fly to the Moon?
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Graduate Gravitational Collapse: How Long Does it Take?
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Graduate You think there's a multiverse? Get real
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High School What Would We See When Traveling to a Star at Light Speed?
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Graduate What Fundamental Force Played a Key Role in the Big Bang?
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A couple of new pix -- M42 and Eta Carina
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Graduate What lies beyond the edge of the universe?
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Undergrad Astrophysics Books by Frank Shu | Student Guide
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Undergrad Heat and Magnetism: How Does the Sun Maintain Its Magnetism?
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Graduate In depth Mars flight trajectory studies
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Graduate Can a singularity expand in volume?
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Graduate How Does the CMB Power Spectrum Relate to Angular Scales?
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Graduate Did space time be created at the Big Bang?
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Graduate What is the Jeans Anomaly and How Does it Relate to the Birth of a Star?
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Graduate Was the announcement that BICEP2 has detected Inflation Gravity Waves premature?
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Graduate How to calculate the mass of a star using redshift?
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Undergrad Is the Big Bang Theory Just a Pseudo-Issue?
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Graduate Is Nature Symmetric? A Deeper Look
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Graduate Is my reasoning correct? Energy "before" the big bang?
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Undergrad Scenarios for end of the universe
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Graduate Why was the flat, no Lambda Universe previously favoured?
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High School Gravity -- Does gravity depends on atmosphere?
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Graduate Heavy water mismatch between comet 67P and Earth's oceans
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Undergrad Space Hazards on ISS: How Much Is at Risk?
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High School Dawn distance to Ceres ≈ distance to moon
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Graduate CMB dipole anisotropies- we are moving towards cmb?
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Graduate Hypothetical Galactic Navigation System Question
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Graduate Assumptions in dark-energy density parameter measurement
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Graduate Giant ring system around exoplanet discovered
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Undergrad What would Kessler Syndrome really look like?
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Graduate Natural Spectrum of the Universe?
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Space Burial: A Futuristic Dream or a Possible Reality?
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Graduate Microbial mats traced in Mars sediment? Noffke's hypothesis
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Graduate First cosmology computer simulations
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Can Radio Telescopes Capture Detailed Images of Asteroids and Their Moons?
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Graduate Comets' High Deuterium-to-Hydrogen Ratios Explained
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Top Sky Viewing Apps for iPhone: A Comparison
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Graduate Expansion of the Universe Question
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Graduate Confused about binary star systems?
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Graduate What Makes the Present Moment Special in an Expanding Universe?
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Graduate Is Space-Time Curvature Just a Force Field?
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Will Dawn successfully enter orbit around Ceres?
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Undergrad Do Pulsars Really Produce Sounds or Are They Just Radio Wave Representations?
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Graduate Event Horizon in a closed, matter (dust) dominated universe
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Undergrad What is the definition of disc scalelength?
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Graduate Pre big bang infinite cold inflation?
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Graduate What Happens to Gravity When an Object Travels at the Speed of Light?
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Undergrad Diameter of Earth-like planet / gravitational force
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Graduate Thermalized components/virialized
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Graduate Most total e-folds from inflation
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Graduate Methods to find exoplanets more easily
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Graduate How to determine the mass of a planet using redshift?
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Undergrad How can you tell what kind of orbit a body will have?
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Graduate Can Weibel Instability Generate Cosmic Magnetic Fields?
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Graduate CMB Hemisphere of Evil: Planck Asymmetry Examined
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Graduate Modelling The Sun’s Magnetic Field
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Graduate What Makes a Black Hole a 'Hole' If It's a Point Mass?
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Undergrad What creates energy in a nova, supernova?
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Graduate Stability of Orbital Resonance Ratios
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Cosmology/QED/Astrophysics Lectures: Ideas Welcome!
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Graduate So what is your favourite theory for the beginning of the universe
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Graduate How massive do neutrinos need to be to account for all dark matter?
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Graduate Integrated Sachs Wolfe Effect - redshifting?
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Graduate Does energy level determine the smallest region of spacetime that can be probed?
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Graduate Paradox on the Chandrasekhar Limit
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Graduate Earth-Like Planets & Iron: Questions Answered
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Graduate Why aren't there any space tugs in use?
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Undergrad How did "Visible light" come into existence?
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Graduate Is Dark Energy a Myth?
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Stargazing How Can I Build a Telescope?
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Where Can I Find Comet Lovejoy in the Sky Right Now?
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High School Earth-Sun Distance: Perfect for Life?
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Undergrad Image reduction and analysis software for windows
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Graduate Diapl - Difference Image Analysis Package
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Graduate Question about the Penrose process
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Graduate Is it possible to understand inflation through Einstein?
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Graduate Understand CMB Anisotropies & Interpret Figures
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Graduate CMB dipole anisotropies & Hubble's Law
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Undergrad Floating in space and angles of galaxies
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Graduate Making sense of distance and speed of expanding universe
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Graduate Quick help with equation P = a * T^4
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Graduate Anti-matter annihilation and the CMBR
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Graduate Size of the Observable universe at the Big Bang Singularity
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Graduate I Simply Cannot Understand Olbers' Paradox -- Finite/Infinite Universe
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Graduate Differential equation for motion within stars
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Graduate What happens in the center of mass of binary star system ?
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Graduate Is Time Quantized? | Scientific American
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Graduate How to estimate/calculate stellar wind from a star?
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Graduate How Does Motion Influence Wave Frequency in Doppler Shift?
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Stargazing How Can I Build My Own Telescope Without a Tube?
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Graduate Are Dark Matter Oscillations Possible Like Atomic Vibrations?
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Graduate Velocity of receding galaxies. Hubble <-> scale factor
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Graduate Apparent size of objects at cosmological distances
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Graduate Why is there an observable universe?
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Graduate Why does the h tensor represent gravity waves?
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Graduate What Factors Influence Radiation Production from Cosmic Ray Particles?
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Undergrad How do we accurately measure distances in space?
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Graduate Density perturbations made simple
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Graduate How much matter goes into making black holes?
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