Astronomy, Astrophysics, Cosmology Forum

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Join in expert discussion on the topics of Astronomy, astrophysics and cosmology. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Stargazing A simple refractor homemade telescope
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Undergrad Are AGNs or GRBs a greater danger for life on Earth?
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Graduate Black holes, white holes and expansion of Universe
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Graduate Super-earth transiting nearby star
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Undergrad What Can the Gravitational Binding Energy Equation Tell Us?
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Undergrad Is there cyclic motion of galaxies?
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High School Are the planets where we expect them to be
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Graduate The Illusion of the 3rd Dimension: A Mathematical Perspective on Space and Time
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High School How do spaceships move in space without any propulsion source?
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Undergrad How Can Physics Enhance Your Science Fiction Space Adventure?
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High School Can We Send a Probe to Proxima Centauri?
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Graduate Proximity of early galaxies to each other
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Undergrad One question about Parabolic and Hyperbolic trajectory.
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Graduate Does the expansion rate of our universe depend on its mean density?
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Undergrad What Are the Key Components That Influence Gravity?
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Graduate Horizon problem - why do we need inflation?
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Graduate What is the Latest Exoplanet Catalog from Geoff Marcy and Paul Butler?
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Graduate What is GJ 1214 b: A Super-Earth Water World Orbiting a Red Dwarf Star?
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High School Big Bang Theory: Fact or Fiction?
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Undergrad Why Is Dark Matter Essential for Understanding Gravity in the Universe?
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Undergrad Does the sun have angular momentum?
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Graduate Rotation Curves and the Influence of Stellar Mass on Orbital Velocity
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Graduate What is our universe expanding into?
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Undergrad Find Apparent Magnitude of Binary Star System w/o Distance
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Huge comet seen on soho web page.
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Undergrad Understanding the Sun's Galactic Coordinates
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Graduate Can Modified Gravity Explain Cosmic Structure Without Dark Matter?
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Graduate Correcting Galaxy Luminosities for Absorption ?
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Tabulation of the Standard Astronomical Filters
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Undergrad Understanding Units of dex^-1 in Number Density Measurements
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Undergrad Liquid water on Venus in early history.
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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 Is Modified Gravity Theory a Viable Alternative to Dark Matter?
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Graduate How do we know that spacetime is expanding
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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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Is the Higgs Particle Just a Myth?
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Undergrad Help deriving this elliptical orbit equation?
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Graduate Future of the universe without proton decay.
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Graduate Can Modifications to Gravity Explain the Accelerating Expansion of the Universe?
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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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What Lies Beyond the Universe?
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Astronomy or Cosmology Christmas gift ideas
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Graduate Ted Bunn on expansion, redshifts and the dangers of 'rubber sheets'
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High School How many arcseconds does Sun travel through sky?
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Graduate What is the relationship between stars, lithium, and exoplanets?
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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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Graduate Redshift and Particle Momentum Decay
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Is Virgin Galactic's SpaceshipTwo the Future of Space Travel?
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Graduate Is the Steinhardt-Turok Cyclic Model Gaining Support?
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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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Undergrad Accelerating Expansion Threshhold
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High School Can the sun be blueshifted due to Earth's rotation?
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Graduate Is the universe an open or a closed system?
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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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Undergrad Stars born in clusters, found in single
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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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Undergrad Evidence of Expansion: Redshifting of EM Radiation
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Graduate Antimatter (in relation to earth)
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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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Graduate Supergalactic cluster waves and geological cycles
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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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Graduate Does recent expansion change the predicted CMB temperature?
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Graduate Hey guys, this is my theory of blackholes and how new parallel universes
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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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Undergrad Are Distant Galaxies Composed of Matter or Anti-Matter?
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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 How do we deal with theories that are hard to prove or falsify?
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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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