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 Big Bang: Escape Velocity Change from >c to <c?
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Undergrad Short existence of liquid water on Mars (explanation related to thin atmosphere)
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Graduate Strange hexagonal shape on Saturn's north pole.
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Free, downloadable solar system simluation.
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Graduate Understanding Virial Theorem: Comparing Equations
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Undergrad Help deriving this elliptical orbit equation?
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Finding the Best University for 16-Year-Old in Greece
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Graduate What is the newly discovered explanation for the evolution of spiral galaxies?
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Undergrad Orbital energy of ellipse and hyperbolic trajectory
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What Caused the Spiral UFO in Norway?
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Graduate Derivation of velocity dispersion from virial theorem?
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Astronomy or Cosmology Christmas gift ideas
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High School How many arcseconds does Sun travel through sky?
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High School Finite Black Holes? Answers for Xap's Question
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Undergrad Why Can't Rocky Planets Exceed 14 Times Earth's Size?
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Undergrad CFD in Astrophysics, ideas for a senior project
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Graduate Is the 20-Minute Difference Between Tropical and Sidereal Year Accurate?
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Is Virgin Galactic's SpaceshipTwo the Future of Space Travel?
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High School Discover the Improbable: The Perfect Conditions for Life on Earth
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Stargazing Telescope Recommendations Anyone?
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High School Can the sun be blueshifted due to Earth's rotation?
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High School Big Bang Theory: Was it Proven Wrong?
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High School Uranus' satellite Miranda question
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Graduate What Is the Fundamental Relationship Between Space and Matter?
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Undergrad What Would Happen if Two Black Holes Got Too Close?
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Undergrad Answer "What Does C=Vλ Mean? Find Energy of Photon
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High School Is there evidence to support past life on Mars?
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Graduate Why do stars orbit around a spiral galaxy in a rosette shape?
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Undergrad Energy required to the Moons orbit
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Undergrad When Will the Sun Transition to a Black Dwarf?
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Graduate Understanding Hilbert Space: A Simplified Explanation
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Undergrad Can Supermassive Black Holes Really Exist and What Evidence Supports Them?
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Radio Waves: Listen to Outer Space & Planets
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Graduate Can white holes really exist as the opposite of black holes?
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Undergrad Are Distant Galaxies Moving Faster Than Light?
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High School Where is the center of the universe in relation to the Big Bang?
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High School Moon & Gravity: Questions & Answers for Beginners
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Graduate Venus Magnetic Field: Dynamo Theory & Slow Rotation
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Graduate Does matter exist only in space and time?
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High School Why the Tides Increase Earth-Moon Distance
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High School The Light From a Star: Comparing Photons & Travel Distance
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Graduate How to scan the frequency at atmosphere by using PIC
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High School What radiation can be detected at 1km high from Earth surface?
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Graduate Calculate Star Mass from Radius: An Integration Approach
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Undergrad Mass of molecular clouds versus stars
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Graduate Nucleosynthesis and light curve of Supernovae Ia
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Graduate Resolving Olbers' Paradox: Is That Quote Wrong?
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Undergrad What is the Titius-Bode Law and its significance?
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Graduate Killing surface gravity for a Kerr black hole
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Graduate How Do Astronomical Factors Influence Planetary Characteristics?
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Undergrad Confused on Gravity: Is Gravitational Force Strong Enough for a Black Hole?
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Graduate Coalescing Supermassive Black Holes
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Graduate Can Super Strong Magnets Counteract Black Hole Gravity?
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Graduate Cloud of neutral hydrogen is moving towards us at a speed
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Graduate What is the Earth's emission spectrum as seen from outer space?
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Graduate Geographic location determination
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Undergrad Voyager & Newton: Orbits and Mechanics Questions
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Graduate The Singularity of a Black Hole: Unanswered Questions
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High School Moon Connected to Earth: What Happens Next?
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Graduate Some help with a X-Ray astronomy question please
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Graduate Could Dark Matter Be Explained by Time Dilation and Virtual Particles?
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Undergrad Where do the 'bars' in a barred spiral come from?
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Graduate Redshift as a distance indicator
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Graduate Thoughts on gravity and space time
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Undergrad Semi-major axis from cartesian co-ordinates
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Graduate Can Space Really Be Created or Destroyed?
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Graduate Einstein's Worm Holes: Derivation of Equation
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Undergrad Space in Atoms: Fusing 2 Together - What Happens?
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Graduate What Are the Orbital Periods and Star Mass for These Hypothetical Planets?
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Undergrad Can Two Particles in a Vacuum Attract Each Other?
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High School Comparing Half Earths: Horizontal or Vertical Shadow Line?
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Undergrad Calculating Orbital Velocities in a Binary Star System
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Undergrad Deriving Kepler's Law: Negative Sign Explained
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Undergrad Is Faster than Light Travel Possible?
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Graduate Schwarzschild and Reissner–Nordström metrics
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Graduate Satellite using rung-kutta method for 4DOF or 6DOF simulation
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High School Can I Make My Own Mirror for Astrophotography Using a 6in Blank?
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Undergrad What Caused the Universe to Expand So Quickly?
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Are the Leonids putting on a show in 2009?
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Graduate Dark energy can escape black holes.
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High School Are there green, purple and pink stars?
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Graduate Doppler shifted blackbody spectrum
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Graduate Mass loss through gravitational radiation
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Undergrad Understand Sideral Time & Calculations - Sept.22, Nov.22, RA 2200 Hours
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High School Travelling to the other world by sending data
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Graduate Seeking Information on the R-process
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High School How Can We Visualize the Milky Way From Within?
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Undergrad Chemical composition of solar system
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Graduate Unravelling the History of Stars: 14 Billion Years
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Graduate Can a photon catch up to your eye within a black hole?
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Lunar Reconnaissance Orbiter Photos
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Undergrad How To Find Angular Momentum of Elliptical Orbits
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Graduate Hydrostatic Equilibrium in General Relativity
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Graduate Jupiter's Equatorial Rotation Period
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Undergrad What Causes Earth's Elliptical Orbit?
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The more you learn, the less you know
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High School Understanding Earth's Rotation: The Effects on Telescope Observations
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Graduate How Does Relativity Affect Mass and Gravity in High-Speed Orbits?
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Graduate Stellar Evolution - Detailed Colour Magnitude (HR) Diagram
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High School The shape of our solar system's orbits.
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