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 I have always wondered if Photons are magnetic and if so are
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Graduate Evolution of Life-Supporting Elements
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Graduate Q: Measured changes in the CMB radiation?
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Graduate High resolution observations of dark matter?
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High School Why does the Earth have a tilt but the moon doesn't?
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Graduate Coordinate conditions in cosmology
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Undergrad Could We Hear the Sun If Sound Waves Travelled Through Space?
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Graduate Black holes swallow space and time?
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Graduate Effect of high intensity electric and magnetic fields on gravity
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Graduate Simple explanation of the Boltzmann Brain paradox
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Undergrad Question about the astro imaging program ds9
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Undergrad Origin of Galaxies and Super Massive Black Holes
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Undergrad Why does gravity collapse and stars explode?
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Graduate Why must dark matter interact weakly?
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Graduate Something about calculating the Age of the Universe
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Graduate Collapsars vrs. QM degeneracy pressure
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Undergrad Hubble's Law and Hubble's Constant
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Graduate Do geodesics of measure zero allow past-eternal inflation?
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Graduate Earth moon motions, distance etc.
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Graduate Is a Black Hole's Entropy Truly Lost?
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High School Help in Understanding Black Holes
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Graduate How do we know black holes exist beyond the theory of relativity?
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Graduate New approach to cosmological bulk viscosity
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Graduate What Other Theories Exist for Modifying Gravity Besides Mond?
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Graduate Dark matter, Mach's ether and the QCD vacuum
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Graduate Thermodynamics at the apparent horizon of the universe
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Graduate CMB at 50: Princeton early universe panel discussion
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Graduate From RTN reference frame to ECI and orbital elements
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Graduate Kinetic equilibrum and chemical equilibrium
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Graduate Any solid theories re: where it all came from?
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Undergrad Solar System barycenter - Orbit of planets
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Graduate Isn't space expansion logically required?
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Nice lunar and planetary conjunction
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Milky Way Composite: Vacation Night Photo
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Graduate Do neutron stars, pulsars, magnetars etc. have weather?
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Graduate How Can we Find the Escape velocity of a black hole
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Graduate I don't understand what is the meaning of phase? (phase space, phase point, etc)
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High School Why do planets and stars flicker?
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High School Large, Persistent Eclipse/Shadow On Earth?
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Graduate Size of the visible/observable universe
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Undergrad What Are the Physical Components of Space?
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Graduate What Does Lambda Represent in Cosmology's Expanding Universe Model?
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High School Avoid Killer Asteroids: Simple Solution Discovered
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Undergrad What materials can a star produce before dying?
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Undergrad Question about interstellar travel
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High School Why does the moon orbit the sun?
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Graduate Are Universal Oscillations Causing Changes in Cosmological Expansion?
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Graduate Geo Coronal Absorption Frequency
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Graduate Solidity & Illusion: Is Universe Solid or Illusory?
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Undergrad Ceres Craters: Investigating NASA's Dawn Animation
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Graduate How Does the Expansion of the Universe look?
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Graduate How to know there is a frequency shift?
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Graduate Does universe expansion separate photons, traveling parallel?
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Undergrad Intensity of light along the iridium flare
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Undergrad Cosmological Expansion: Is There a Limit?
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Undergrad Distance of GJ 436b to GJ 436 - doesn't work out.
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Graduate 800+ ultra-diffuse galaxies in Coma cluster
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Undergrad What Causes Radio Blackouts During Space Capsule Descent?
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Graduate Graviton vs Einstein's Curvature of Spacetime
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Universe Splitter iPhone App: Randomly Split Universe?
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High School After supernova explosion sound is created....
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Graduate Like spacetime -- can sound be taken as a fifth dimension?
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Undergrad Has the Value of G Constant Changed Recently?
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Graduate Spatial Expansion Interpretation with Quantum Graphity Model
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Graduate Does Infinity mean 'potential' Infinity?
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Undergrad How do different bodies in the Solar System affect Earth's gravitational pull?
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Undergrad How did Kepler derive his laws WITHOUT law of gravitation?
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Graduate Baryon oscillation peak a cosmological standard ruler
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Graduate Higgs Bosson, manipulate gravity, 4 dimensional space.
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Graduate Determining The Size and Age of Our Universe
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Undergrad Variations between Sunrise & Sunset timings
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Graduate Are there current efforts on ritz-type cosmology?
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Graduate What force is needed to overcome expansion?
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Graduate NYT: David Sobral et al "CR7" PopIII galaxy article
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What Does the Observable Universe Look Like?
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High School Living in a Rotating Space Habitat: Perception and Challenges
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Graduate Speed of light inside a black hole
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Undergrad Understand 5th Dimension: Get Help Understanding 4th Dimension
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Graduate Argument of the Perihelion Projection
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High School What absorbs Ultraviolet radiation?
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Graduate Could Velocity Exceed c in Comoving Worldlines?
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Stargazing Create homemade reflector telescope by own
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Undergrad Where is my calculation of sun angle incorrect?
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Undergrad Possible observation of Pop III stars....? -NY Times article
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Graduate Is Time Measured Differently Due to Time Dilation Since the Big Bang?
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Graduate Effect of Rotation on the Earth and Planetary Disk(s)
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Graduate How Do Planetary Distances Influence Retrograde Motion Durations?
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High School The Mystery of Gravity: Doubts Answered
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Graduate Marginal evidence for cosmic acceleration from Type Ia SNe
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Graduate Infinite Universe and Parallel Universes
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Graduate Could Lee Smolin's Fecund Universes Theory Solve Black Hole Information Paradox?
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Undergrad Difference between conductors and empty space
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Are Multiverses and Intelligent Life More Than Just Beliefs?
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Undergrad What would it be like to be at a Lagrange Point?
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Graduate Speed and / or expansion rate of the Universe?
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Graduate What is the role of dark energy in the expansion of the universe?
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Graduate Gravitational Slowing Justified in Flat/Near-Flat Universe
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Graduate Introducing the Model T time unit "Lizzie": key to H_infinity
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Graduate How Can I Measure Stellar Aberration Accurately?
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Graduate Interstellar Exocomets Density & Impact Probability
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