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.
Nice ongoing planetary alignment
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Undergrad Juno Flyby Anomaly - Searching for Answers
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Undergrad Infinite Universe: Can It Ever End?
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Graduate How can light have momentum if it has zero mass?
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Graduate Is a Magnetic Levitation Space Launcher Possible?
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Graduate Is Multiverse proven by Plank data?
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Graduate Metric expansion misunderstanding
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High School Is this a photograph of water on Mars?
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Graduate Is the Universe's Expansion Actually Slowing Down?
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Graduate MOND and the missing baryons problem
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High School What are the ways we can search for alien life?
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Graduate No Dark Matter or gravity modification for flat rot
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High School Explore the Solar System with a Dynamic Simulator for Teaching - Free Download
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Proper motion of Ursa Major (Big Dipper)
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Graduate Gravitational lensing as a way of observing Milky Way?
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Graduate The Inflaton Field And Repulsive Gravity
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High School Move Mass in Space: How Much Pull?
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Graduate Expansion then Contraction....an infinite Elastic Collision?
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Graduate Saturn: Helium Rain, or non-indigenous planet?
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High School What Are the Physical Limitations of a Dyson Sphere?
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Graduate Time, Mass & Space: Does Time Stay Consistent?
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Graduate Heliocentric polar orbit crossing the Earth's orbit twice
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Graduate Is the universe fine tuned for life
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Graduate Collision of massive star with black hole
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Undergrad Kepler's 2nd across a system of planets
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High School Suggest a Quantum Physics Book for a 16 Year Old
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Graduate Question re Galaxy Rotation Curve
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Graduate Mass of a Black Hole: Answers & Questions
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Graduate Likelihood of confirming past life on Mars
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Undergrad Cosmology looks beyond the standard model
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High School Venus Info: Is It Hot & How to Cool It Down?
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Graduate Consequences of Overlapping Event Horizons in Supermassive Black Hole Mergers
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Graduate What happens to matter when it enters a black hole?
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Is the Celestron Omni XLT 120 Refractor Telescope worth the investment?
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Undergrad Calculating Universe Density: Cosmology Equations
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Graduate Can Neutrons Emit Light Without Electrons to Swoosh Them Away?
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Graduate The Universe Never Expands Faster than the Speed of Light
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Undergrad At what speed is our universe expanding?
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Undergrad Does an Expanding Universe Alter How Quickly Light Travels Through Space?
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Graduate Will a bouncing cosmology lose information
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Graduate Why Does Increased Baryon Loading Shift Power Spectrum to Higher Multipoles?
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Graduate What Happens to Electrons in Synchrotron Radiation?
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Graduate Are Atoms Just Empty Space If Fundamental Particles Are Zero-Dimensional?
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Graduate Alternative Theories: Ghirardi-Rimini-Weber and the Many Worlds Interpretation
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Graduate What Is the Impact of Shape on Escape Velocity in an Expanding Universe?
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Graduate Why should the Bullet Cluster focus light?
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Undergrad Understanding Observing Frequency and Its Significance in Radio Astronomy
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Stargazing What are the upper physical resolution limits on telescopes?
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Graduate Comparing Radio and X-Ray Galaxies: Redshift vs. Emission Mechanism
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Graduate First detection of direct collapse black holes?
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Graduate Possible to derive an approximation of G from a Saros ?
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High School Could Life Exist on Mars with the Discovery of Flowing Water?
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Undergrad Does the black matter has weight?
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Graduate Solving Freidmann Equation: Understand Calculations & Cosmology
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Graduate What can the Anthropic Principal predict?
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Graduate Event Horizons = Cosmological Horizons?
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Graduate Confusion re Laniakea Super Cluster
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Undergrad Dependence of rotational angular velocity of planets
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Graduate What is the purpose of the Einstein stress-energy tensor?
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Undergrad Why are photons affected by gravity?
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Undergrad About doubling the mass of the planets and the sun of our solar system
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Graduate How Does Synchrotron Radiation Influence Observations in Radio Astronomy?
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Graduate Radiation from the surface of a star
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Graduate Gas Mass Calcuation in Galaxy Cluster
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Stargazing Why Aren't There Telescopes on the Moon?
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Graduate Spaghettification and gravity in theory of relativity?
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Graduate Are Interstellar Extinction Variations Misleading Cosmological Measurements?
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Graduate Time at the big bang and in very early time after that
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Graduate Population 1 vs Population 2 Stars: Metal Rich vs Metal Poor
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Graduate Is the X-Ray Mass of the Coma Cluster Accurately Measured?
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George Will endorses space research
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Graduate Random Walk Question re Inflation
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Graduate Does the Bullet Cluster Disprove MOND and Challenge ΛCDM?
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Graduate Origin of Quantum Perturbations?
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Graduate Good 1st year grad level texts in galaxies and cosmology
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Graduate How Does the CMB Frame Differ from Other Frames in Relativity?
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High School I've heard gravity can "fling" stuff, how does this work?
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Graduate Computing osculating orbital elements
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Graduate How many hypothetical particles do we need
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Undergrad Why can dark matter make our planets move in same velocity?
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Graduate Fine tuning, muitverse and a double standard
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Graduate How does gravity get out of a black hole?
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Graduate Destruction of Solar System by passing Star
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Graduate What is the evidence for dark matter in the solar neighborhood?
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Graduate How Do Scientists Determine the Composition of a Star's Core?
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Graduate Do Galaxy Clusters follow De Vaucouleurs' Law?
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Graduate Why don't all neutron stars collapse into black holes?
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Graduate Distinction between special and general relativity
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High School Sun & Horizon: Why Does it Look Different?
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Graduate Re Dark Matter and the Horizon Problem
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Graduate What Causes the Higher Peaks and Damping Tail in the CMB Power Spectrum?
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Undergrad How Would a Halved Earth Mass Affect the Moon's Rotation Period?
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Graduate Is the location of galaxy X in the universe constant?
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Lunar super eclipse Sept. 27th. 2015
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High School Find 1.25" Focuser for 8" Newtonian Telescope
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Graduate Negative energy is repulsive, but PE is negative, so?
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High School Need reliable resources on basic astronomy and quantum physics
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Graduate How to measure CMB anisotropies *In Practice*
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Graduate Pre-Big Bang Environment & Rules: Insights on the Known Laws of the Universe
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Graduate Does Gravity Gravitating Alter Cosmology?
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