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 Neutron Star Collisions: Effects & Stages
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Graduate Revisiting the Big Bang: Galaxy HUDF-JD2
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Graduate Hartle-Hawking Model (How the Universe Can Appear From Nothing)
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High School One question [size of the universe]
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Stargazing What is the bottom limit of telescopes and why can't they detect visible light?
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Undergrad Can Black Holes Consume the Entire Universe?
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Graduate Does the Universe's Expansion Affect Time Travel?
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Graduate Hubble Ultra Deep Field baby galaxy examination
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Graduate Nearby supernova risk discussed by Sigurdsson
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Graduate T Pyxidis Supernova: Energy Release Compared to SN1054
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Graduate Why is the dark matter: baryonic matter ratio about 5:1?
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Graduate Orbital period decay and gravitational waves
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Graduate Understanding the Limits of the Universe
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High School Is the Universe Expanding Without Boundaries?
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Graduate Current CMB photon number density?
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High School Does the moon cause the flux and reflux of the tides?
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Undergrad How Do We Measure the Size of the Universe?
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Graduate Effects of Magnetic fiedon the Dark Energy and Cosmic String
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Graduate Gravity on the surface of Gliese 581 d
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High School How did universe start to expand
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Fermi Telescope Spots Giant Explosion in Space
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Graduate How to calculate r.m.s radius of a N-body system?
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High School If the universe is infinite, does it mean that everything exists?
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Graduate Are Hubble's Sphere and the Universe's Age Coincidentally Similar?
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Graduate Do black holes evaporate or go bang ?
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High School See the Diffraction of Moon Light at Night
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Undergrad Inflation - can someone please explain it?
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High School Paper on the physics of big bang: what should be included
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Graduate Shouldn't All Black Holes Have EM Wave Halos?
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Possible misenterpretations of the known universe
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Graduate A giganitc wavefuntion of the universe = determinism?
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Graduate What Are the Biggest Mysteries of the Universe and How Can We Understand Them?
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Graduate Cellular phones and reverse SETI
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Graduate Is a flat universe better imagined as an expanding sphere or a cube?
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Graduate What Is the Physics Behind the Expansion of Space?
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What Are the Different Theories on the Creation of Our Universe?
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Graduate Understanding Magnitude Systems in Extragalactic Imaging
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Graduate Producing a CCD Image: Corrections, Calibration, Subexposures
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High School What is the Direction of Orbiting Planets around the Sun?
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Graduate Distinguishing between flatness
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Graduate De Sitter universe, is it compatible with darkenergy?
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Graduate If Hubbles constant is decreasing?
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Graduate Does any model predict the mass (or total energy) of the observable Universe?
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Graduate Variation of Density Parameters with Redshift
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Graduate Accelerating Expansion: Is there a Positive Feedback Loop?
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Graduate Universe expanding or time speeding up?
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Graduate Potential Vacuum Energy: Does it Double Every 11B Years?
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Graduate Cosmological constant or dark energy or vaccum denisty/energy/energy density
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Graduate Confused about the event horizon
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Graduate Is Space-Time Really a Woven Fabric?
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Graduate Thermodynamics in Friedman World Models
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Graduate Expansion of space and looking back in time
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Graduate Could dark energy have existed before the Big Bang?
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Graduate Big Bang Expansion: White Hole Theory
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Undergrad How to calculate the orbit of a minor planet?
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Undergrad Why Do Some Galaxies Have Warped Structures?
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Undergrad Why has no one seen Neptune with the naked eye?
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Undergrad Is dark matter hiding in plain sight?
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Graduate Is the Inertial Frame Defined by the Universe's Center of Mass Unique?
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Fat Guy vs Skinny Guy: Universe Size Dependent?
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Undergrad Does Gravity Affect Nuclear Reactions in Space?
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Graduate The Conundrum of the Speed of Light and the Expanding Universe
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Undergrad Edge of Universe: What's Beyond the Limit?
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Undergrad Question about expanding universe VS gravity pull.
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Undergrad Are LMC, SMC approaching the Milky Way ?
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Undergrad Qualifying Radiation Detectors for Space: Homework Help Needed
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Graduate Why does gravity cause lower orbit speed at smaller radii?
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Graduate Evidence for pre Big Bang physical universe?
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Undergrad Death of Mars: How a Volcano Could Trigger Planetary Extinction
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Undergrad Calculating Kinetic Energy for Rotating Planets
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Stargazing My New Telescope - Review and EP Advice
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High School Is a Used Telescope a Good Choice for a Beginner Astronomer?
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Graduate Why are blue-shifted galaxies concentrated in specific sky directions?
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Undergrad What is the true scope of our universe?
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Graduate The metric expansion of the Universe
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Graduate Mercury's Orbital Precession Anomaly
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High School WR104 Gamma Ray Burst: Fact or Fiction?
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Undergrad Astronomers use earth-based spectroscopy
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Is Nibiru Really Going to Collide with Earth in 2012?
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High School Will the Moon escape Earth's orbit in billions of years?
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Graduate What is the true essence of the universe beyond human perception?
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Graduate Why is the term 'Big Bang' a misnomer?
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Graduate How to Calculate the Scale of Venus's Atmosphere Using the Barometer Equation
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Undergrad Calculate Aphelion Distance & Velocity of Comet at Perihelion
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Graduate What Is the Temperature Differential of Hawking Radiation?
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Undergrad Is There a Massive Time-Image Gap in Observing Distant Galaxies?
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Undergrad What Causes Pluto's Elliptical Orbit Around the Sun?
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High School Was there more than one Big Bang?
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High School Are Quasars Still Present in Our Universe?
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Graduate How Does the Integrated Sachs-Wolfe Effect Support the Concept of Dark Energy?
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Graduate Cephid Variables: Finding Distance from Parallax & Magnitude
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Graduate What Would an Infinite Universe Look Like at the Time of the Big Bang?
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Graduate Are Black Holes Real? Investigating Gravitational Collapse
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High School How do I calculate light years to years?
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Undergrad Transmission Bandwith though space
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Graduate Did the Big Bang Create Time or Reveal an Infinite Paradox?
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Graduate Pauli Exclusion Principle: Finite Creativity or Philosophy?
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Graduate Is this not mathematical evidence that the universe is an open system?
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Undergrad Trying to find out how exactly we find out how big the visible universe is.
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Dark matter discoverd? link inside
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