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.
Undergrad Why do the Sun's/star's luminosity increase during the main sequence?
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Undergrad Standard gravitational parameter
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High School Why at the south hemisphere the sun rises from the west?
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Undergrad Why Is There a Hexagon Shaped Cloud on Saturn?
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Undergrad Space Based Power: Is it Practical? Safety Concerns & Benefits Explored
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Undergrad How much mass do you need to create Gravity?
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Graduate If the gravitation has very very tiny deviation from inverse square law！
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Undergrad Gravity verses electromagnetic attraction
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Graduate Can empty space or emptiness conceive a form from which matter arise?
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Undergrad Does Time Change at Different Depths Inside the Earth?
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Graduate Help with Life expectancy of Main Sequence stars.
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Undergrad What are causing the Eccentricity of the planets?
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Graduate Background radiation and intensity
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Stargazing New to astronomy, what telescope should I get?
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Graduate Space at Singularity: Pre Big Bang Theory?
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Undergrad Image Processing Software; suggestions?
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Graduate Big Bang starting Mass (mater/antimatter)
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High School Relative Intensity in Spectra: What Does It Mean?
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Undergrad Calculating L2 Lagrangian Point: A Beginner's Guide
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Graduate Tolman-Oppenheimer-Volkoff equation
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Graduate Textbook on Numerical Celestial Mechanics
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Graduate What is the Statistical Challenge in Understanding Dark Matter and Energy?
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Graduate 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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Undergrad Epsilon Eridani: 2 Asteroid Belts and an Icy Ring
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Undergrad Position of Planetary systems at given time
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Graduate 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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High School What Is the Composition of Black Holes?
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Investigating the Authenticity of a Shooting Star Picture
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Undergrad View from the Earth-Moon L5 point?
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The Smell of Space: Mystery & Explanation
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Graduate Mass-Radius relation of a Neutron star
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Graduate Supernova gravitation field and Newton
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Graduate Polytropic Models: Solving Problem at Slide 5
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Graduate Use Sun to dispose of radioactive waste?
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High School How Has the Universe Expanded Over 13.7 Billion Years?
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High School Find Longitude of Sun - Learn How Now
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High School Spider free mount for secondary mirror
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Graduate Can Variance of Variances Define Higher Dimensions?
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Graduate More about that gamma burst (the brightest ever recorded)
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Graduate Zeroth Law of Thermodynamics
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Graduate Can a Star Exist with Negative Pressure?
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Undergrad 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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Graduate What is the Solar Evaporation Time?
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High School Hurricane size whirlpool on the Sun
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Undergrad Throwing paper airplane towards space question
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Graduate Singularity in reference to blackholes and right before the big bang?
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High School Earth's Orbit & Tilt in N. America: Winter Closest, Summer Farthest
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Graduate Virial Theorem in Stellar Dynamics
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Undergrad Why is the closing velocity of Andromeda and our galaxy so high?
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Graduate JDEM/Beyond Einstein, is it still alive?
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Graduate Astrophysics Help: Calculating Mass of Hydrogen Converted in Sun Over 10B Years
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Undergrad The Secrets of the Universe: Measuring Age through Light Travel
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Graduate Abundances for Small Magellanic Cloud
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Undergrad Calculating the Earth's Elliptical Orbit around the Sun
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Graduate Will a Halved Earth Orbital Period Affect Solar and Sidereal Days Differently?
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High School 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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Graduate Center for Exoplanets and Habitable Worlds (news of improved instrumentation)
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Graduate Counting Subfields of F_p in Algebra
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High School Where Can a 9th Grader Find Advanced Astronomy Resources?
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Graduate What Aspects of the Universe Were Inflated During the Big Bang?
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Undergrad Figuring out mass of a star based on diameter
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High School Prove that the earth goes around the sun
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Undergrad Simple question about certainty/confidence in astronomy
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Graduate Do Population II Stars Have Planets?
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Undergrad Can Light Travel Forever in Space While Baryonic Matter Decreases?
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Graduate Do Orbital Inclinations Affect Hohmann Transfer Efficiency?
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Graduate Are We Real? Universe Baryons, Photons, Asymmetry
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High School Are G-forces smaller when traveling in space?
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Undergrad Light travelling through a black whole
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Undergrad Apparent Magnitude of Binary Star System
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Graduate Can a black hole be stabilized through Hawking radiation and mass feeding?
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High School Why Do Stars Appear to Move Away From Us?
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Graduate Time coordinate in the rain frame
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Undergrad No Green Stars: What's the Story?
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Graduate Understanding the Chandrasekhar Limit: Neutron Stars & Spin Effects
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High School Why the earth is rotating along its axis?
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Graduate Does a Schwartzchild blackhole have a singularity?
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Stargazing Need Help - Learning to use a telescope
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Undergrad Benchmark redshifts to tell your kid brother or sister
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Undergrad Question about the orbiting plane of the moon
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Undergrad Single Dish Radio Astronomy Inefficiencies
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High School Understanding Mass, Energy & Space: How Much Energy Does it Take to Move 1 Ton?
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Graduate 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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Undergrad Can we reach Mars using thrusters and maintain a constant velocity?
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Undergrad HELP .The Azimuth and Altitude of Star Vega
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Undergrad Does Geological Evidence Support the Existence of Planet X?
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Graduate Can anything fall into a black hole?
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Graduate Why Do We Get an Einstein Cross Instead of a Skewed Ring?
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High School Building a Telescope with 6" Mirror & Focal Ratio of 3.3 - $50
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Undergrad Earth's magnetism and Sun's temperature
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Graduate Identifying Cepheid Variables from Spectrum
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Graduate Is dark energy constant to emtpy space?
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