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.
Finite vs Infinite: Does Size Matter in the Universe?
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Is a Symmetrical 'X' Planetary Alignment Possible in a Solar System?
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Please answer My Many New Bee questions on a Black hole.
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Brightness of ISS in Earth's shadow
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Neutron stars and magnetic fields
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This first thing that Kills a human in Space?
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De Broglie equation and black holes
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Stargazing Viewing Saturn from a 6 telescope
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Can Energy of Creation Connect Us to Our Origins?
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Stargazing Where should the secondary mirror be placed in a concave mirror telescope?
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Stargazing Why does Saturn move so much in my telescope?
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Is It Possible to Have Infinite Mass?
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What Is the Empty Space into Which the Universe Expands?
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Planetary Alignment (nothing to do with astrology)
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What is the percentage of heavy element of the sun?
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BH Mergers: 8 Images & Computer Simulations
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Can dark matter explain the flyby anomalies?
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Measurement of distance in space
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Rail guns for launching projectiles to space
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Measuring Star Diameter in Foreign Galaxies
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Earth's interior heat vs Gravity
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Does Asymmetry in Spacecraft Flyby Trajectories Cause Unexpected Energy Gains?
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What Causes the Colorful Cross in Photos of Sirius?
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Stability of Counter-Planets: Examining the Possibility of Dual Planetary Orbits
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How Can You Capture Star Spectra for Astronomical Analysis?
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Is Space Infinite? - What Do You Think?
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Is the bright star I saw in the west sky Venus or another planet?
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Could the Big Bang Have Been A Cyclical Event?
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Can our Nuclear weapons destroy a Neutron Star?
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How was Voyager 2 used to determine the orbits of Uranus and Neptune?
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Stargazing Struggling to Focus with New Telescope? Here Are Some Tips!
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Planet Gravity: What Makes Objects Attract?
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A Star's Life, (Full Explanation)
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Anti-Gravity and Black Holes: A Theoretical Analysis
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Calculating the luminosity density of the universe
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Question about the edge of the Universe
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Can an Observer Safely Enter and Observe the Singularity Inside a Black Hole?
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How Does Space-Time Influence the Fall of an Apple?
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Water on Enceladus - Cassini's Revealing Findings
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Space Expansion and Light question
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Questions About Black Holes & Event Horizons
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Equation to find the speed of a distant star
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Unusual Redness of Betelgeuse: A Mystery in the Night Sky?
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Can Inter-Universe Energy Transfer Create New Realities?
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What happens to a Black hole when they die?
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Black Holes have no gravity below the event horizon? - How can that be?
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The Next Naked Eye Comet: What to Expect & When
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Sir Author Eddington and Einstein's GTR
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Can Black Holes Decay and How Does This Affect Their Event Horizon?
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Fantastic astrophotograpy book now out
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Why Is a Single Wavelength Used to Calculate Hubble's Diffraction Limit?
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Asteroid 2009 DD45: Close Approach to Earth March 2nd
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What would happen to Earth's orbit if it increased in mass or lost velocity?
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What will happen to Earth when hit by a Neutron Star at the Speed of Light?
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Black Holes: Is the Hubble Image Real?
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  • Poll Poll
Are Visitors from Outerspace Likely To Be Friendly?
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HII regions, on-the-spot approximations
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Why Aren't Meteors Heated by Friction?
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How gravity make planet to rotate?
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Beginner Astronomy: Telescope Advice & Tips
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Space in an Atom: What is the Nature of this Space?
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Stargazing in Georgia: Left or Right?
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Can someone explain curved space time?
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Gravity has to have an effect on time,when gravity can curve space ,it
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Astrophysicist Jobs: What's Available?
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Calculating Orbital Velocity for a Satellite Orbiting Earth
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Is 2009 Really the Year of Astronomy?
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Sun's Corona Paradox: Temperature Defying Laws of Thermodynamics
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Can We Detect Moons Around Earth-Sized Exoplanets?
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Could a Moon Be Transformed into a Mini Sun?
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Is the Sun Anchored? | Experiments & Feedback
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What is singularity? [Black Hole ]
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Is this the approximate gravity of Mars?
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Singularity - Black Hole or Naked
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Confused about monochromatic flux
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Friction in space as approaching light speed
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Observing antiquark annihilation
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Can Aliens Observe Plato Lecturing in Academia?
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Stargazing Kepler Telescope is so productive?
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Understanding the 4-Dimensional Universe Expansion: A Philosopher's Perspective
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Why Do Orbits Take an Elliptical Shape?
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Friction necessary for planet formation?
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Stargazing Saturn with new DMK, grayscale camera
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What is the magnitude of the magnetic field in solar wind?
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How do we tell how far away a gamma burst was?
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Why Are Planetary Orbits in Our Solar System Mostly Coplanar?
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Question about orbit determination with find_orb
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Ages of Stars from CMD: The Accuracy of CMD vs. Photometry Explained
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Stargazing Has an astronaut ever captured a photo of a solar eclipse from space?
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Precession betrays Nemesis position?
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How many exoplanets with an atmospheric oxygen signature would be necessary?
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Creating oxygen(co2) out Of hydrogen
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Stargazing I want to make an astronomical telescope
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May 10-12 1999 The Day the Solar Wind Disappeared
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At what point, if any, would a spaceshp burn up in space?
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How can I track Earth's distance to the sun on a specific date?
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What can be done about space junk
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Surviving the Sun's Disappearance: The Life Expectancy of Earth's Inhabitants
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What Are Simple Unsolved Problems in Astrophysics for Beginners?
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Star Distribution - Types, Galaxies & Time
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