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 Given expansion, finally each particle will have only 1 neighbor
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Graduate Why Stephen Hawking says universe can create itself from nothing?
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Graduate Singularity Paradoxes: Nothing or Something?
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Undergrad What Is Space in Physics?
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Graduate Did Quasars Play a Role in the Formation of Galaxies?
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Conspiratorial cosmology - the case against the Universe
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Undergrad The time it takes the Earth to go around the Sun.
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Graduate When Will the Big Crunch Happen According to Current Models?
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Undergrad Why are Cosmic Rays and Hard X-rays Essential for Heating Molecular Clouds?
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Redshift FAQ article development
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Graduate Is Inflation the Key to Understanding a Flat Universe?
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Undergrad How big was the Universe 13 billion years ago?
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Graduate Energy has mass & therefore gravity. Yet dark energy is repulsive ?
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High School The Earth-Sun Relationship: A Matter of Perspective
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Graduate HR diagram: magnitude - luminosity relation
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High School How does the sun burn without oxygen?
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Graduate Gravitational Acceleration Differences in a Pulsar: Calculation and Comparison
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Graduate Decent papers/articles on black holes
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Graduate Trying to understand the oscillation of electrons in the magnetic fiel
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Graduate How did the CMB Lorentz frame get chosen?
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Graduate Does the boundary of the causal universe function as an event horizon?
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Undergrad Cosmological constant calculation
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Graduate Higgs/vacuum stability and the universe
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Graduate Understanding the Nature of WIMPS: Bosons or Fermions?
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Graduate Definiton of Schwarzschild radius clarification request
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Undergrad How should I see the CMB picture
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Graduate A Gravitational Entropy proposal from Ellis, Tavakol, and Clifton
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Graduate Problems with living outside the Heliosphere?
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Graduate Possible reason for dark energy (?)
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Graduate What slowed or stopped inflation?
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Graduate Article on New Planck Satellite data
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Graduate Composition of the Universe can be Derived from PI?
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Undergrad Life in Universe: Is Intelligent Life Inevitable?
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Interesting facts about the Universe
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Stargazing New cosmic model parameters from South Pole Telescope
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Undergrad Can anything truly be stationary in our constantly moving universe?
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Graduate A history of the universe using the new Planck numbers
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Graduate How Does a Comet's Path Relate to Relativity and Spacetime?
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Undergrad What Are the Fastest Moving Objects in the Universe?
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Graduate Where in the universe am I absolutely still ?
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Graduate How Does Particle Size Influence Emissivity in Circumstellar Dust?
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Graduate Large Scale anomaly in Planck data
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Graduate Is Wikipedia's Explanation of Olber's Paradox Misleading?
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High School From where did our earth get its initial velocity ?
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Undergrad Best tables for data of objects in our solar system?
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Graduate The Higgs mechanism and the Beginning of the Universe
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Graduate Planck Mission Reveals Universe Features: String Theory Hits
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Graduate Inflation of singularity at moment of evaporation?
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What Exciting Discoveries Will the Live Planck Results Reveal?
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Undergrad Mystery of the Pushed Away Black Hole
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Undergrad Exploring the Habitable Zone: Limits and Possibilities for Detecting Alien Life
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Undergrad Evolution of a star from a nebula
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Graduate Is the universe large and finite, or infinite?
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Graduate How can the universe be infinite, if it has a finite age?
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Graduate On the formation of larger bodies in space after dust attraction.
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Graduate What is a Vacuum in General Relativity?
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Graduate Understanding Magnetars and Neutron Stars
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Graduate Neutron Stars: Quantum or Classical Objects?
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Graduate Questions about nuclear physics inside a star
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Undergrad Gravitation as answer to whether the Universe is infinite?
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Undergrad Interpreting Gravitational Lensing Images?
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Undergrad Time Space Matter Characteristics
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Graduate What would happen if a black hole sucked in a cloud of hydrogen gas?
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Undergrad Can Planetary Gravity Flatten an Egg-Shaped Planet?
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Graduate Is Dark Matter Absorbing Photons and Emitting Undetectable Radiation?
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Graduate Differences between polarisations and temperature anisotropies in the
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Graduate History of speed of the expansion of the universe?
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High School Looking for some good websites for Physics and Cosmology
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Graduate What speed do quasars eject matter out the galaxy?
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Photo of Jupiter's moons with cellphone
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Graduate Do Black Holes *actually* exist?
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Graduate Could the LHC potentially form a black hole?
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Undergrad Near earth Asteroids and a space elevator
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Graduate Normal&good question about redshift
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Graduate Could the universe just be a piece of something bigger?
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Graduate Is dark energy or dark matter created to keep the Cosmological constant
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Graduate Evidence of Dark Matter within the Solar System?
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Graduate Questions about Nuclear Fusion in the Sun
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Graduate Gravitational Waves: Cosmic Inflation Equation
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Graduate How to calculate orbitals of celestial bodies using calculus?
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Compiling Common Star Names for FK5 - Help Needed!
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Graduate Can We Really Understand Black Holes If Nothing Can Escape Them?
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Stargazing Telescopes 101: Intro Guide For Beginners Under $500
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Graduate Is the big bang singularity really a rapid expansion of spacetime?
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Graduate Can we expect stars to become visible only in infrared after a while?
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Graduate Does Matter Truly Occupy Space or is it Merely Energy in a Certain State?
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Graduate For how long the Cosmic Microwave Background was emitted?
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Graduate Can Gravity Act Faster Than Light?
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Graduate Rethinking Cosmology (Steinhardt)
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High School Why are we crashing with Andromeda?
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Graduate Dark Energy Confusion - Unraveling the Mystery
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Graduate Poincaré recurrence and maximum entropy
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Graduate Why is Mars so easily visible to the naked eye?
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Undergrad What Form Does Matter Take When a Star 'Explodes'?
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Undergrad See far away objects in space in real time?
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When Will We Know If Planck Discovered B Mode Polarisation?
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Graduate Coincidence of asteroid and Russian meteor at same time.
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Graduate Largest structure in the universe discovered so far
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Graduate Original location of the Big Bang
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Undergrad Is the Moon's Orbit Influenced by Earth's Warped Space and Tidal Friction?
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