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.
What is a Photon Sphere: Definition and Properties
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What is the Mathematical Definition of Orbital Eccentricity?
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What is Laplace-Runge-Lenz vector
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Kepler's Laws: Definition & Equations
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What is Irreducible Mass in Black Hole Physics?
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What is Irradiance? Definition, Equations & Explanation
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What are the effects of Hawking radiation on black holes?
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What Describes the Expansion of the Universe?
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What is the Friedmann acceleration equation
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Frame Dragging: Definition & Equations
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What is the Critical Density in the Context of Universe Expansion?
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What Are Closed Timelike Curves in Black Holes?
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What is Mass Inflation? A 5 Minute Introduction
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How Does Binet's Equation Determine Acceleration in a Central Force Field?
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The Effect of Planets Rotation within its Galaxy?
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Astronomy Resources for Learning & Research
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Russia plans to leave International Space Station
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Andromeda vs Milky Way dust emissions
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The application of of Fermi Dirac statistics in the white dwarf
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Gravity causing distances smaller than a Plack length?
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Data on the Velocity of the Celestial Bodies Orbiting a Galaxy
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How was the core temperature of sun estimated ?
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Several questions regarding the nature of the universe
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Name Exoplanets: IAU Plans to Name 305 Exoplanets
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Is there a "missing light crisis"?
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Traveling to Andromeda in 2 Months with a Spaceship
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Is Redshift Only a Result of Universal Expansion?
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Conversion between density and column density
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Do Objects in Space Float or Maintain a Fixed Position?
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Stopping a star from going supernova
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Could we read a newspaper from a satellite image?
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Chandrashekhar paper on white dwarf
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Chandrashekhar limit for relativistic fermion gas
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How Do You Evaluate a Line of Sight Integral for Dark Matter Annihilation?
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Why can we see light emitted near the beginning of the universe?
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Start planting trees on mars now
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What Triggers a Supernova Explosion During a Star's Core Collapse?
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Momentum transfer when object falls into black hole
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Is Intelligent Life in the Universe a Waste of Space?
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Why Do Io and Titan Exhibit Unique Surface Phenomena?
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CMB cold spot explanation proposed (looks good)
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Moon occultation of Mars tonight
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Hubble Finds Vast Reservoir of Gas Near Milky Way
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Understanding and Creating an O-C Diagram
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Why does A black hole need a massive center
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Are Wormholes Really Impossible Without Exotic Matter?
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Calculating the Density and Volume of Matter in the Expanding Universe
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Battery in Space? Current Flow in Vacuum?
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Vale Bill Bradfield - The loss of a comet hunter
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Trio of Big Black Holes Found in Galaxy Smashup
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Discovering the Oldest and Most Distant Star: HD140283 Subgiant Star
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Why do most galaxies have a flat, disc-like shape?
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Large Body Orbiting a Small One?
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Does anyone know which paper that this figure come from?
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Ratio of matter to radiation density
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Structure of galaxy and the laws behind it
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Earth as a Capacitor: Lightning & Rain
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Interaction of three black holes
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Can Black Holes Be Broken Apart?
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Radio Waves from Stars: Investigating the Mysteries
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Where Do Electrons Go in the Plasma State of Stars?
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Is Dark Energy Actually the Pull of Black Holes?
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Properties of Matter in Vacuum (Space)
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Could Black Holes Expand in Negative Dimensions and Create a Negative Universe?
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Did Anyone See Asteroid "Beast" Fly By Earth?
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What Are Some Recommended Astronomy Books for Laypersons?
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Simple explanation of the lunar highlands problem
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Give Me Some Perspective: Size of Universe?
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Space-Time & Matter: Explaining the Difference
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Unidentified Constellation: Deciphering Star Patterns and Their Meanings
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Can Black Holes Increase in Mass?
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Numerical Facts about the Milky way's halo
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Inclination of Equatorial North Pole relative to Galactic Equator
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Why does a singularity have to exist?
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Why Are Statistical Significance Maps Used in Cosmic Ray Anisotropy Studies?
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If every event is governed by one or more laws
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40,000 years taken for light to reach here?
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If black holes don't exist then neither does the cosmic horizon?
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Calculating Redshift for Objects in the Universe
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Martians observe Mercury solar transit
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Stargazing Whats an innovative idea for a nuclear telescope?
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How to identify that light in the sky
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Focal length short and long. Which to choose?
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Dark matter distribution around black holes.
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Stargazing Celestron Powerseeker 60AZ Telescope
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Tracking the International Space Station
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Is Saturn's 63rd Moon Being Born?
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Possible research topics for high redshift galaxies and AGN
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Stars Creating Elements Heavier than Iron
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Can a body in space form a sphere?
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Voids inside atoms and voids in space?
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How can Google Sketchup simulate Sun and Earth movement for seasonal changes?
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Speed of Light Affecting Objects' Appearances?
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Sun & Moon Coincidence: A Remarkable Fact
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Traces of Theia Found on The Moon
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What is your favourite episode of Cosmos: A Space-time Odyssey?
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Discover Mega-Earth: Kepler-10c 17x Heavier Than Earth
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Tidal Acceleration and planetary rotation
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New Cosmos: A Spacetime Odyssey 2014 TV Series
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Understanding the Expanding Universe and Its Impact on Earth's Distant Future
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