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 How do astronomers measure an objects angular size?
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My Hero: Waid Mobile Observatory
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Undergrad Will the Expanding Universe Break the Attractive Forces Between Particles?
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Undergrad Explore Venus: Mystery, Atmosphere & Surface Features
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Undergrad Greek Astronomers & Telescopes: Determining Magnitude & Brightness
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Graduate Galaxies recede faster than light
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Graduate Is a Euclidian Model the Solution to the Gravity=Geometry Conundrum?
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Glimpsing a Mysterious Whizzing Object in the Night Sky
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Undergrad How Can We Quickly Calculate Distances to Stars Without Parallax?
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Graduate Is the Expansion of the Universe Leading to Heat Death?
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Graduate Early Reionization: HUDF-JD2 Examined
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Graduate Could There Have Been a Virtual Particle Era Before the Planck Time?
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Graduate Horizon scale at the onset of cosmic acceleration
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High School What Are the Best Introductory Articles on the Origins of the Universe?
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Undergrad Are Black Holes Responsible for Galaxy Formation?
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What are the notes for Course Navy: Astrodynamics Halo?
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High School Between the moon and the Earth a Spaceship travels
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Graduate Blackhole Question (involves Light)
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Undergrad F=mv^2/r and Geosynchronouse orbits
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Undergrad Galaxy Death: Is Starbirth Rate Decreasing?
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High School The Weight of Black Holes: Physics Behind Tiny Masses with Giant Implications
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Stargazing Reflecting Telescopes: Hole in Picture at Focus?
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Stargazing Trig in Telescopes: Theta Formula & Astronomy Sites
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Graduate Galaxy Rotation Curves Without Non-B. Dark Matter
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High School Space-Time dimentions & plane of Sxistence
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Graduate Can a powerful telescope reveal the true limits of the universe's distance?
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Graduate Is the Universe Shaped Like a Dodecahedron?
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Graduate [Andromeda] Fast traveling stars
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High School Project in relation to Einstein on geo-reactors
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Graduate Is the universe still expanding?
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Graduate Quantum Geometry and Schwarzschild Singularity?
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Graduate How can accurate orbits and masses be determined in astronomy?
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Parallel Universe: Existence & Speculations
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Graduate Fastest neutron star, 1100 km/second
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Stargazing New 135mm/f2.8 Lens & Rig: My Experiences So Far
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Graduate Could dark matter be error in GR or temporal effect
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Undergrad Is the Big Crunch a Mathematical Possibility for the Universe's End?
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Undergrad Looking for an Introductory Book on Orbital Mechanics?
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Undergrad Unraveling the Mystery of Dark Matter
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Graduate Solar/Stellar Model Overview & Parameters
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Graduate AIAA - Textbooks in Aerodynamics and Space Engineering
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Graduate Omega pointe and the Big crunch theories
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Graduate Halo and Lissajous Orbits: Powered or Natural?
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High School Relation between the moon's gravitation and the level of ocean
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SpaceTiger has wandered into the cellar
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High School What would be the effects of Earth not having a moon?
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High School Saturn Satellites: Collapse & Reconstruction
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Did an Asteroid Really Hit Antarctica in 2004?
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Graduate What's the acceleration of our galaxy?
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Undergrad Question on stellar absorption spectra
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Graduate Most distant gammaray blast detected
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Graduate An Old quasar in a Young Universe?
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Undergrad What are some recommended objects for a semester project in optical astronomy?
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Graduate Space Ship Collision: How Far Did Meteorite Come?
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High School Is the Milky Way Moving Towards the Hydra Constellation?
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Graduate The solar systems and space probes
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Undergrad Theories about the beginning of the universe
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Graduate Clustering of primordial black holes
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Graduate Formula for solar radiation pressure
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Course :astrophysics ,introduction ,e.a
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High School Identification of an object in the sky
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Undergrad Universe expansion and merging galaxies
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Undergrad Saturn's Rings Shifting: New Findings
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Undergrad Do Light Wavelengths from the Sun's Edges Differ from Its Center?
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High School Stars move as the night progresses
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Graduate Absorption in 'CMBR' wavelengths - observations? processes?
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Can someone help me identify this object in my photo?
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Undergrad Why Does Planet's Molten Core Create Magnetic Fields?
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Space & Military: Militarization of Space?
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Undergrad Can a Galaxy Collapse Inward Over Time?
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Graduate Speculation is detracting true astrometry
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Graduate What Is the True Nature of Empty Space?
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Stargazing What do you recommend is the best way to clean a lense(telescope)
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Mars rover adds hill climbing to list of accomplishments
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How many tv programs are about astronomy, science?
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Graduate Observational Dark Energy - SN1a wiggle room?
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Graduate The origin of cold dark matter halo density profiles
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Stargazing How is the principle of the operation of radio telescope?
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If you could go anywhere in time and space
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Undergrad For those who think life is rare
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Graduate Can You See the Entire Universe Before Entering a Black Hole?
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Undergrad What If the Earth's Orbit Was Changed?
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Undergrad [astrogeology] measuring atmospheric density
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Graduate What resources are available for studying higher dimensional quantum cosmology?
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Mystery Light: Can Anyone Explain What I Saw in the Sky?
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Graduate Did condensation accompany the initial big bang expansion?
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Undergrad Everything about Big Bang theory
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High School Confused on Orbits: Ellipses vs Circles
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Graduate Isn't space expansion expectable?
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Power Outage & Mysterious Sky Objects in My Neighborhood
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Graduate 1 Parsec = 3.08568025 × 10^16 meters
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Undergrad A supernova can out light a entire galaxy
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Undergrad Help: Application of Optical Fibre In Astronomy?
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Graduate Does My NBody Simulation Look Accurate?
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Undergrad Solar Energy Q: Mass of Sun Decrease/s?
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Undergrad Is Mounting a Telescope on the ISS a Viable Option for Atmospheric-Less Viewing?
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Graduate Mature stars in ancient galaxies
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High School Why Do Planets Rotate on Their Axis?
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High School What Makes Neutron Stars So Unique?
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Undergrad Is there a super-massive black hole in the center of our galaxy?
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