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.
Undergrad What Is the Difference Between Surface Brightness and Apparent Brightness?
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Undergrad Newest exoplanet close enough to study its potential atmosphere
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Undergrad Basic Astrodynamics: Understanding Total Energy
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Undergrad Why do some planets occlude the Sun while others do not?
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Undergrad Earth's orbit & precession affected by Venus & Jupiter?
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Undergrad Center of Lift vs. Center of Thrust
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Undergrad Can I use the Fourier Transform to analyze the Sun's Spectrum?
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Undergrad Galaxy Mass - How much is stellar/gas?
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Undergrad Use 3D laser scanning to map Outer Space?
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Undergrad Q: Limit on a moon's orbital radius due to sun's gravity
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Undergrad How was Galileo able to observe Venus's phases?
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Undergrad Juno Flyby Anomaly - Searching for Answers
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Undergrad Kepler's 2nd across a system of planets
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Undergrad Understanding Observing Frequency and Its Significance in Radio Astronomy
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Undergrad Does the black matter has weight?
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Undergrad Dependence of rotational angular velocity of planets
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Undergrad Why can dark matter make our planets move in same velocity?
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Undergrad How Would a Halved Earth Mass Affect the Moon's Rotation Period?
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Undergrad Can Neutrinos Escape Black Holes?
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Undergrad Why don't black holes become stars again?
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Undergrad How much does weight affect re-entry into the atmosphere?
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Undergrad How do we determine distances of objects in space?
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Undergrad Why Does Earth Appear Mostly Blue from Space?
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Undergrad Planet at the center of mass of a binary star system
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Undergrad Moon's crust as fractured as can be
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Undergrad Astronomers find galaxy cluster with bursting heart
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Undergrad Who first found the Heliocentric or Geocentric Distances
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Undergrad Young gas giants fly close to their suns
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Undergrad Could a Tidal Lock Cause the Earth to Stop Rotating?
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Undergrad Data for Earth Orbiting Satellite & Ionosphere: Research Help
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Undergrad A question about the flatness of galaxies
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Undergrad How Can Empty Space Be Curved?
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Undergrad Q: Personal magnetic fields: Protection from space radiation
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Undergrad Help with Aladin Contrast for Galaxies, Stars & Planets
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Undergrad Elliptical Orbit of Sun Around Milky Way
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Undergrad Confusion About the Physics of Orbiting Bodies
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Undergrad Blackbody Radiation and the Inverse Square Law
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Undergrad Can time exist without space and vice versa
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Undergrad Traveling to space aging more slowly is true?
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Undergrad How do we know galaxies are exactly where we see them?
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Undergrad Minimum possible warning for deadly comet/asteroid
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Undergrad Distances in km/s vs mega parsecs or light years
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Undergrad Why isn't the Oort Cloud shaped like a disk?
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Undergrad Gravitational Influence of Stars in a Galaxy
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Undergrad Thermodynamics behind the heating of Saturn's moon Enceladus
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Undergrad Which field deals with this(Astronomy,Astrophysics) ?
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Undergrad Galactic Black Holes: % & Types Explored
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Undergrad How the satellite parts get damaged
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Undergrad Neil deGrass Tyson "Orbital Erosion"
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Undergrad Help with Venus Transit AU calculations
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Undergrad Peanut-shaped near-Earth asteroid imaged by radar
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Undergrad New rocky exoplanet discovered is the closest to Earth
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Undergrad How did planets get their Orbits?
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Undergrad Astrophysics uses wave optics or geometrical optics?
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Undergrad Term for space in front of the expanding universe.
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Undergrad Earth-Like Planet orbits Sun-Like Star
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Undergrad Is the Fermi Gamma Ray Detector Capable of Detecting Individual Photons?
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Undergrad Guidelines for including "atmosphere" in a body's "diameter"
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Undergrad Intersecting Orbits of Binary Stars: A Visual Guide
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Undergrad Do quasars and blazars exist today?
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Undergrad Function driven solar system model.
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Undergrad How can we see galaxies behind other galaxies?
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Undergrad What Causes Gravity in the Cosmos?
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Undergrad Calculating mass of Milky way Galaxy
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Undergrad Could We Hear the Sun If Sound Waves Travelled Through Space?
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Undergrad Question about the astro imaging program ds9
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Undergrad Origin of Galaxies and Super Massive Black Holes
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Undergrad Why does gravity collapse and stars explode?
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Undergrad Solar System barycenter - Orbit of planets
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Undergrad What Are the Physical Components of Space?
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Undergrad What materials can a star produce before dying?
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Undergrad Question about interstellar travel
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Undergrad Ceres Craters: Investigating NASA's Dawn Animation
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Undergrad Intensity of light along the iridium flare
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Undergrad Cosmological Expansion: Is There a Limit?
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Undergrad Distance of GJ 436b to GJ 436 - doesn't work out.
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Undergrad What Causes Radio Blackouts During Space Capsule Descent?
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Undergrad Has the Value of G Constant Changed Recently?
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Undergrad How do different bodies in the Solar System affect Earth's gravitational pull?
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Undergrad How did Kepler derive his laws WITHOUT law of gravitation?
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Undergrad Variations between Sunrise & Sunset timings
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Undergrad Where is my calculation of sun angle incorrect?
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Undergrad Possible observation of Pop III stars....? -NY Times article
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Undergrad Difference between conductors and empty space
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Undergrad What would it be like to be at a Lagrange Point?
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Undergrad Venus Transit - What should be a simple problem
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Undergrad Pluto's moon Nix and its wild tumbling orbit
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Undergrad Discover Earth's Plasma Rings | Cleo Loi Proves Existence of Plasma Tubes
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Undergrad Is it theoretically possible for a star to orbit a planet?
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Undergrad Milky Way Mass: 60,000 Ly from Galactic Center
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Undergrad Why do small bodies stay in orbit around large bodies?
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Undergrad Is the Density of Points in an Interval Twice as Much with Double Length?
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Undergrad Understanding the Units of Permittivity of Free Space in Coulomb's Law
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Undergrad Are Asteroids Formed by Collisions or Accretion?
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Undergrad Can Kepler's 2nd Law be applied to more than one planet?
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Undergrad Question about Kepler's 1st law and barycentric orbits
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Undergrad Can light pressure affect the motion of galaxies?
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Undergrad Calculating an Escape from Earth's Gravity: Can It Be Done?
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Undergrad Could you send an object into space completely without fuel?
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Undergrad Distance Comparison: Converting 48 Distance Modulus to Meters
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