Astronomy and Astrophysics Forum

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Join in expert discussion on the topics of Astronomy and astrophysics. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Textbook on Numerical Celestial Mechanics
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What is the Statistical Challenge in Understanding Dark Matter and Energy?
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Intensity-wavelength graph for emission spectra; why is frequency in the x-axis?
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Hubble down, Repair mission delayed
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Epsilon Eridani: 2 Asteroid Belts and an Icy Ring
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Position of Planetary systems at given time
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Dipole Moments of the Planets and the sun
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What Do Non-Scientists Think of Color-Enhanced Astronomy Images?
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Does Moon have North and South Poles ?
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What Is the Composition of Black Holes?
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Investigating the Authenticity of a Shooting Star Picture
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The Smell of Space: Mystery & Explanation
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Mass-Radius relation of a Neutron star
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Supernova gravitation field and Newton
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Polytropic Models: Solving Problem at Slide 5
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Use Sun to dispose of radioactive waste?
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How Has the Universe Expanded Over 13.7 Billion Years?
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Find Longitude of Sun - Learn How Now
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Spider free mount for secondary mirror
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Can Variance of Variances Define Higher Dimensions?
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More about that gamma burst (the brightest ever recorded)
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Zeroth Law of Thermodynamics
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Can a Star Exist with Negative Pressure?
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Will Sudan Experience a Predicted Minor Impact Tomorrow?
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Stargazing Discover the Capabilities of 25+ Meter Telescopes Beyond Engineering Projects
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What is the Solar Evaporation Time?
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Hurricane size whirlpool on the Sun
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Throwing paper airplane towards space question
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Singularity in reference to blackholes and right before the big bang?
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Earth's Orbit & Tilt in N. America: Winter Closest, Summer Farthest
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Virial Theorem in Stellar Dynamics
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Why is the closing velocity of Andromeda and our galaxy so high?
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JDEM/Beyond Einstein, is it still alive?
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Astrophysics Help: Calculating Mass of Hydrogen Converted in Sun Over 10B Years
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The Secrets of the Universe: Measuring Age through Light Travel
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Abundances for Small Magellanic Cloud
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Calculating the Earth's Elliptical Orbit around the Sun
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Will a Halved Earth Orbital Period Affect Solar and Sidereal Days Differently?
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Why Do We See the Same Stars All Year?
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What are we waiting for to get into space?
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What New Images Did Messenger Capture During Its Mercury Fly-by
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Center for Exoplanets and Habitable Worlds (news of improved instrumentation)
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Counting Subfields of F_p in Algebra
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Where Can a 9th Grader Find Advanced Astronomy Resources?
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What Aspects of the Universe Were Inflated During the Big Bang?
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Figuring out mass of a star based on diameter
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Prove that the earth goes around the sun
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Simple question about certainty/confidence in astronomy
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Do Population II Stars Have Planets?
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Can Light Travel Forever in Space While Baryonic Matter Decreases?
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Do Orbital Inclinations Affect Hohmann Transfer Efficiency?
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Are We Real? Universe Baryons, Photons, Asymmetry
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Are G-forces smaller when traveling in space?
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Light travelling through a black whole
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Apparent Magnitude of Binary Star System
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Can a black hole be stabilized through Hawking radiation and mass feeding?
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Why Do Stars Appear to Move Away From Us?
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Time coordinate in the rain frame
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No Green Stars: What's the Story?
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Understanding the Chandrasekhar Limit: Neutron Stars & Spin Effects
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Why the earth is rotating along its axis?
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Does a Schwartzchild blackhole have a singularity?
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Stargazing Need Help - Learning to use a telescope
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Benchmark redshifts to tell your kid brother or sister
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Question about the orbiting plane of the moon
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Single Dish Radio Astronomy Inefficiencies
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Understanding Mass, Energy & Space: How Much Energy Does it Take to Move 1 Ton?
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How long does it take for a white dwarf to go supernova through accretion?
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Stargazing Is a Radio Telescope Less Sensitive on the Galactic Plane?
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How many more dwarf planets can be named after deities?
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Can we reach Mars using thrusters and maintain a constant velocity?
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HELP .The Azimuth and Altitude of Star Vega
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Does Geological Evidence Support the Existence of Planet X?
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Can anything fall into a black hole?
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Why Do We Get an Einstein Cross Instead of a Skewed Ring?
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Building a Telescope with 6" Mirror & Focal Ratio of 3.3 - $50
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Earth's magnetism and Sun's temperature
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Identifying Cepheid Variables from Spectrum
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Is dark energy constant to emtpy space?
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Collapse calculation (surce code?)
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Stargazing Shaving mirror for reflecting telescope
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Help Calculating Parallax Error - Physics Forums
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What Is the Fourth Dimension: Time, Space, or Something Else?
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Hundreds of Rogue Black Holes in Our Galaxy - Is Earth at Risk?
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Matter, Antimatter, and Micro Black holes
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Inventing Moons and their Eclilpses-help
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How do we know how much visible matter exists?
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Orbital question(elliptical vs circular orbit)
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Evaluating the age of a universe
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Blue Shift objects; is there a list/table?
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Can Relativity Explain the Possibility of Aliens Visiting Earth?
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Does MySpace Tom have a public personal email?
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What is the true nature of dark energy and its gravitational effects?
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Understanding Matter and Antimatter Interactions in Black Holes
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Identifying a Bright Celestial Object in FL, USA - Eraniamayomii
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What is the cause of the rotation of the planets
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3 questions on Physical Cosmology
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Like a diamond in the sky(with video)
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Motion of randomly generated stars
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Can Two Stars in a Static Universe Ever Collide Due to Gravitational Influence?
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