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.
Graduate How would you see an Event horizon?
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NASA Confirms Water on Moon - Exciting News!
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High School Question about the orbit between Mars and Earth
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Does anyone know how to find this paper?
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Graduate Kerr Black Hole & Keplerian Stable Orbit
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Stargazing Understanding the Magnification of a Telescope: Why is M = f_o / f_e?
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Undergrad Pale blue dot: what causes the bands?
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Undergrad A non-technical explanation for FTL quasar motions
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Graduate A method to predict visibility of the international space station
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Graduate How Does Gravity Propagate Backwards in Time?
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Graduate Is it possible for a single super-massive black hole
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High School Is Our Moon Moving Away? The Mystery Unraveled
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High School Why is the Sky Blue? Understanding Rayleigh Scattering Explained
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High School Reasons why LCROSS is a safe mission
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Graduate Restructuring of the solar system theory
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Graduate The Universe Model: A Simple Study of Infinite Hydrogen Atoms
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Graduate How to much mass does it take to change Neptune's Orbit?
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Graduate Nuetron star collapses to B.H., a final plunge of matter and energy?
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Graduate Unravelling the Mysteries of Meteor Showers
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Graduate A question about dark energy and the expansion/acceleration of the Universe.
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Graduate Could Everything Be Contracting to a Point Instead of Accelerating Away?
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Undergrad Calculation of orbital speed for given eccentricity
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Undergrad How can artificial gravity be created on space stations using rotating rings?
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Are the Perseids meteor shower the best in recent years?
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High School Supernova's Gamma Rays and Comets
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High School Difference between Supernova vs. Nova?
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Undergrad Is Star Formation Just a Matter of Lag Time?
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Weightlessness discoveries in the history of the human race
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Graduate A theory and questions about physics/astro and quantum.
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Graduate Inverse relationship - neutron flux density with sunspot cycle
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High School Origin of Planets: How Was Our Planet Formed?
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High School Why Can't Space Ships Use Propellers or Jets for Manoeuvrability?
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Undergrad Question about a Carl Zeiss lens
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Undergrad Planet Rotation: Questions & Answers
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Undergrad Why Do Revolving Bodies Have Elliptical Orbits?
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Graduate Are Black Holes Unfalsifiable and Therefore Not Science?
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Graduate Absence of dust on moon and material sciences
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Undergrad What is the True Density of Space?
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High School Earth's Movement and Atmosphere with a Black Hole Sun
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Undergrad Textbook on Mathematical Astronomy
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Undergrad Elliptical orbits and focal points
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Graduate Can Gravitational Lensing Cause a Star to Appear Twice Simultaneously?
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High School Mercury not travelling in a straight line?
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What do u recoment for somwhone thats intrested in astronomy?
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High School Galactic Suite and space tourism
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Undergrad Help with Orbital Mechanics: First Post
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Graduate Jets from Black Holes - do they carry momentum?
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Undergrad What Is the Gravity Value on Neutron Stars?
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Stargazing Good Beginner Telescope: Best Options Under $200
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High School Southwest Sky Constellations: Most Recognized Patterns
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Graduate What Happens to a Stationary Bowling Ball in an Expanding Universe?
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Graduate Mapping Underground Caves/Tunnels on the Moon/Mars
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Graduate What is the universe expanding into?
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Undergrad Help with Spectroscopy in Astronomy
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Undergrad Unraveling the Mysteries of the Expanding Universe: Age and Size
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Graduate Trying to comprehend the explosive power of a gamma ray burst?
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High School Why Do We Experience Night in Our Universe?
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High School Space.com says intergalactic hydrogen gas absorbs all optical light
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Undergrad Chance of Planet Formation without Stars
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Undergrad Why most of the planetary orbits are ellipitical?
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High School Why is earth's path is elliptical?
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High School So, what are all the known paradoxs in Astronomy?
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Undergrad A hypothetical space elevator question.
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Graduate Main sequence lifetime problem
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My dwarf is bigger than your dwarf
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Graduate Planet's Julian Date of a point in orbit
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Undergrad Planets <-> solar systems <-> galaxies
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Comet C/2008 O2 McNaught photos?
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Graduate Mass-luminosity relation problem
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Undergrad What equations are needed for calculating Keplerian orbital mechanics?
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Graduate Using Technology to stop the expansion of space.
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Undergrad What Would Happen if You Cut the Earth in Half?
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Undergrad Find Accurate Weather Logs for Your Astronomy Observations | Natski
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High School Energy and momentum flux in the sun and Newton's 3rd law.
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Graduate How to Fix an Error with the Setup of IDL/Healpix?
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Undergrad How Far Can a 300 mm Telescope Resolve a Double Star Separated by 10 AU?
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Undergrad Changing Earth's Rotation: Impact on Gravity and Mass Loss
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Graduate A god switchs off the nuclear fires in our sun tonight, do I have to worry?
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Graduate How do we accurately measure the speed of light without frames of reference?
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Graduate Are L4 and L5 Lagrange Points Stable with M1/M2 ≥ 24.96?
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High School Period of Aquila (Latin: 'eagle') constellation
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Graduate I need to shield Earth's Gravitational force.
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Graduate Could gravitational waves form interference patterns?
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Graduate Is the Kinematics of 3D Space Truss Affected by Closed Loops in the System?
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Graduate Is Gravitational Shear Limited to Gravitational Lensing?
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Graduate How Does Time Dilation Impact the Calculated Age of the Universe?
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Undergrad Age of Stars: Calculating & Assessing Helium
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Undergrad Stars and planets made out of antimatter?
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Graduate Help with Black Holes: Determining Energy at Distance r
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Sky Color on Planet Orbiting Zeta Tucanae (F9V, CI 0.576)
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High School What Can We Learn About the Zodiac Constellations on October 20th?
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Graduate How is orbital energy transferred between celestial bodies?
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High School Why do planets of our solar system orbit in rings not spheres?
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Graduate Stuff I always wondered about astrophysics
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High School Difference between axial tilt and inclination
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Undergrad Gravitational Attraction: Could Dark Matter be Explained?
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Undergrad How can you estimate mass of star?
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High School What is the Law of Gravity and Why Do Masses Attract?
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Undergrad Books on Astrophysics/Nucleosynthesis
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Graduate Cosmic microwave background radiation
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