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.
High School What is the Speed of the Lunar Terminator?
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Messier 45: Image from Oct 6th/2013
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Graduate Gamma ray bursts (GRB's) and the Ordovician Mass Extinction
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Undergrad Dark matter comprises over 80% of the universe
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Graduate Info on tests done in the past for expanding universe
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High School How do clocks keep up with time?
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High School Compare weights at equator and poles?
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High School Shape of Universe: What is Its Form?
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Graduate Explaining the Big Bang Theory for Dummies
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Graduate Photon pressure from energy density
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Undergrad Sunspot plotting and angular velocity
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Graduate What Lies Beyond the Observable Cosmos?
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Graduate How does rainbow gravity reshape our understanding of inflation?
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Graduate Is Dark Flow Evidence of Other Universes According to Planck Data?
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Undergrad Calculating the Distance and Parallax of a Star: A Practical Guide
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Graduate What happens to gravity in one dimension of space?
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Graduate Centrifuge and Radial Bouyancy in space
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Undergrad Connection between right ascension and time
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Graduate Physics & Cosmology: Dimensionless Void Pre Big Bang
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Graduate Can Matter Be Transferred Between Universes?
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Graduate Suppose gravitons do leak into Calabai Yau spaces
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Undergrad Can Extra Dimensions Solve the Central Singularity of Black Holes?
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Undergrad What is a gravitational sling-shot?
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Graduate FRW Universe with Equation of State: Examining Singularity at Big Bang
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Graduate Two kinds of flatness? cosmological constant?
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Graduate How to calculate when an object will be directly
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Graduate The linearization of the metric of curved space-time
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Graduate Why is this theory simply ignored?
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Undergrad How do atoms move through space?
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Graduate What Do Canonical Quantum Gravity Models Tell Us About the Big Bang?
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High School Is black hole a theoretical concept or a natural phenomenon?
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Graduate Universe is infinite-no beginning and no end
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Undergrad Values of Right Ascension which are best for an observer
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Graduate Problem understanding how universe is infinitely flat
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Graduate Predicting the Radius of the Sun as a Red Giant with SSM
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Graduate Is Euclidean space an affine space?
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Graduate Are galaxies net importers or exporters of mass/energy?
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Undergrad How has CMB research affected modern technology
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Graduate Temperature & Survival at Big Crunch
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Graduate Is the Observable Universe Flat Despite Gravitational Warping?
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Undergrad Fate of Galaxies: Will Stars be Pulled into Black Holes?
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Graduate Accelerating, Expanding Universe Questions from a Novice
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Graduate Consumption of a galaxy by its central black hole
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Graduate A small black hole goes thru a toroidal hole.
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Graduate Effects of super massive blackhole on galactic movement
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Graduate What is space in contrast to void?
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High School Evidence of water found in Martian soil
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Undergrad Asteroid Impacting Venus: Will it Strike or Explode?
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Graduate Time & Gravity: How Much Slower on Earth?
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High School Why does Earth have an axial tilt
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Graduate Can the shape of the universe be inferred from the CMBR?
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Graduate Earliest Photons: Quark Era & Neutrino Decoupling
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High School Explaining Gravity: A Simple Question Answered for Kids by an Expert Astronomer
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Graduate Is the microwave background radiation still decreasing?
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Graduate War, space, and the evolution of Old World complex societies
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High School Is the Sun Really White? Investigating a Crackpot Theory
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Undergrad Is the inner core of earth affected by the moon?
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Graduate Gravitational waves analogous to photons and EM radiation?
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Undergrad How can I use the Newton Method to find the eccentric anomaly for Mars?
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Graduate Rewinding a black hole - Can a spinning black hole become a star?
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Graduate How Does Lower Moon Mass Affect Its Orbit Distance from Earth?
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Discovering the First Binary Star System: The Fascinating Binary System Story
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Graduate What about 2nd law of thermodynamics in Cyclic Universe Model?
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Graduate How Much Mass Energy Does a Black Hole Re-Radiate?
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Graduate Traveling to other universes in an infinite multiverse
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Graduate Turn a sinusoid into a elliptic orbit
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Graduate Quantization of Gravity: Testing with CMBR Polarization | Krauss, Wilczek
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High School Do 'Space Rainbows' Exist Outside of Planetary Atmospheres?
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Graduate Find Perifocal in Kepler: Reconcile Answers from x0, y0, z0, vx0, vy0 & vz0
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Graduate Galileon Cosmology Explained: Summary & Overview
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Graduate Could Dark Energy be a form of Dark Matter
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Graduate Nature of radiation on interplanetary space exploration
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Undergrad Could Evil Parallel Universes Really Exist?
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High School Is It Possible to Explore Comets with Today's Technology?
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Graduate Planetary habitability in proximity to nebulae
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Undergrad Optimal Distance for Collision-Free Earth Orbit
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Voyager: at edge of our solar system
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Graduate Goodbye Big Bang, hello black hole?
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High School Microscopic Alien life found on British Balloon?
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Graduate Einstein field equations and scale invariance
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Graduate Is there a chronology in the multiverse?
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Graduate Is energy conserved in the expanding universe?
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Graduate Could Space Be an Energy Conversion Rather Than a Result of the Big Bang?
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Graduate Travel through different vacuum phase
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Undergrad Star is expected to be torn apart in the center of our Galaxy
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Graduate Is the Universe Expanding into Nothing or Something?
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Graduate Is the expansion of the universe relative to our clocks and rulers?
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Undergrad The Big Bang: Light Before Matter?
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Graduate Orbital period of eclipsing binaries
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Graduate Question about pre-CMB & Lepton Number
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Stargazing What Type of Brass Telescope Do I Have?
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Graduate Energy and mass, equal in amount in the universe?
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Graduate Can Einstein's Field equation explain inflation?
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Graduate Is the Universe Really Expanding?
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High School Why Do Some Galaxies Have a Spiral Shape?
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Undergrad Question on Red shift applied to objects within the same galaxy
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Undergrad Understanding Frame Dragging: Explanation and Effects
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Graduate A temporally and spatially open universe
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Graduate Distribution of mass - from decoupling to present
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Graduate How Does Heliocentric Julian Day Enhance Eclipsing Binary Analysis?
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