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.
Undergrad Why does the sun appear to move eastwards from Earth?
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Graduate Is there a boundary present for our universe?
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Graduate How Is the Age of the Universe Measured Given Relativity and Expansion?
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Undergrad Active Region AR2192 heading towards the limb
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Undergrad About the size of the Universe and distance between galaxies
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Graduate How do E Folds relate to real distance?
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Graduate Have theories been formed yet on how to stop a black hole?
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Does anyone NOT believe heat death is the final destination?
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Graduate Problem with Surface Brightness & cosmological parameters
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Graduate How to understand Friedman equation
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Graduate Excluding a simple dark matter candidate
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Undergrad Future of Universe: Big Freeze, Big Rip, Big Crunch, Big Bounce?
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Graduate Why can the universe be expanding inward away from point of singularity (POS)?
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Graduate First Measurement of the Ancient Solar System's Magnetic Field
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High School Can a Camera Be Built to See Stars in Daylight?
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Undergrad Our galaxy is one of the biggest
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Graduate Is the Universe Heading Towards a Big Crunch or Eternal Expansion?
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Graduate Matter at the core of neutron star
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Graduate Half of All Stars in Galactic Halos: Potential to Rethink Mass Estimates?
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Undergrad Flux --> Apparent magnitude ( only 1 source )
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Graduate A Mental Conundrum -- The Big Bang & the Speed of Light
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Graduate Pairwise velocity dispersion in Cosmological simulations
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Undergrad The mass of the sun at its beginning
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Graduate Does the Universe always have the same mass, or can it leak into other realms?
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Graduate Why Does the Hubble Sphere Expand Despite the Changing Hubble Constant?
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Graduate Interstellar the movie and real physics
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Undergrad Unraveling the Mystery: The Big Bang and the Origin of the Universe
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Graduate Is Newton's third law applicable everywhere?
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Graduate Solar System Dynamics, advice for a intern.
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Graduate Proton-electron mass ratio; changed? how much?
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Undergrad Shape of Galaxies: Explaining Spiral & Elliptical Structures
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Undergrad Calculating Sun's Luminosity: Step-by-Step Guide
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Undergrad Solar System inside a black hole
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Graduate What Theories Exist About the Edge of the Universe?
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Graduate What is the Ideal System for Running a Nuclear-Powered Heat Engine in Space?
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Ison Comet will be brighter than the moon
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Have you seen the meteoric smoke-ring?
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Graduate Can I Use a Telecentric Lens with an Afocal Telescope?
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Graduate Cosmological Curvature: A $10 Bet with My Professor
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Undergrad Fire in Low Gravity: Visualizing a Biodome Blaze
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Graduate How Did Supermassive Black Holes Grow So Massive So Quickly?
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Graduate Schonberg-Chandrasekhar mass for low mass stars
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Undergrad Help calculating The mass of a Black hole (homework help)
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Graduate Plank length / space expansion question
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Graduate Explaining the Big Bang: The Science Behind the Universe's Rapid Expansion
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"Planet formation captured in photo"
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Worship, Reference Points & Time: A Story of an Old Lady
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Graduate Does Antimatter exist in the universe anymore?
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Graduate What are peoples thoughts on the fact that at the exact limit of our universe.
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Graduate Is Dark Energy the Answer to the Accelerating Universe and Big Bang Conundrums?
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Graduate What is the Breakdown of the Milky Way's Mass?
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Graduate How Did the First Stars Form Without Supernova Compression?
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Undergrad How did Einstein know the properties of space and time
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Alan Guth:Inflationary Cosmology live stream 10/31
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Undergrad Can someone explain the mathematics of this formula for Venus' orbit
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Virgin Galactic's SpaceShipTwo Lost in Test Flight; One Pilot Reported Dead
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Undergrad How Can We See the Light from the Big Bang if We Expanded from the Same Origin?
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Graduate Does Positive Curvature Dominate FRW Cosmological Models in Inflation Theory?
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Graduate What prevents a star from collapsing after stellar death?
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Undergrad What Came Before the Big Bang?
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Graduate What Causes Red Shift in Cosmology: Expansion of Space or EM Red-Shift?
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Graduate Zero gravity in spiral galaxy center?
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High School Tides: Does Moon's Rotation Affect Earth?
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Graduate Big Bang ruled out as origin of lithium-6
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Graduate Cosmological redshift: Where does the energy go?
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Mom's New Camera Captures the Night Sky!
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Graduate Unorthodox "space" elevator idea
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Graduate Could the Event Horizon of black holes be the edge of expanding universes?
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Undergrad Why do galaxies and solarsystems form disks?
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Graduate Doubt about Frame Dragging and planetary revolution
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High School The Space Between Atoms -- Teaching Middle School
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Undergrad Unraveling the Relationship Between Magnetic North and Solar East
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High School UFO or Dead Pixel? What's Flying Across the Moon?
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Undergrad What causes red shift in the universe?
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Undergrad Why do the constellations appear to move differently in different seasons?
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Graduate BH to Sun, back of the napkin calculation of solar mass
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Undergrad Expanding Universe: Verifying Space Expansion Through Galaxies
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Graduate How/why are pocket universes created during eternal inflation?
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Graduate Zero-point energy density evaluation
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Graduate Results from TLE & SGP4 propagation - don't seem right & with interpretation
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Undergrad Can a planet with a thin atmosphere have oceans?
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Graduate Which Stars Cast the Milky Way's First Light?
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Graduate Stars that look older than the universe
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High School How Can You Find M31 in the Light-Polluted Skies of Central USA?
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Graduate Question regarding to acceleration in the rate of expansion of our cosmos
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Graduate Is CNO cycle more life friendly than H->He?
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Easy astronomical objects to see from the city
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ISS Visibility If Painted Black?
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Undergrad What is the Density Change Towards the Centre of a Gas Giant?
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Graduate Sinking instead of expanding universe?
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What Makes the Andromeda Galaxy So Captivating in This Stunning Image?
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Graduate FRW pertubations in overdense and underdense regions
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Undergrad Would the sky be red if the atmosphere was thicker?
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Graduate Non equilibrium boson distribution function
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Graduate If the sun becomes a black hole will its schwarzschild radius change?
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Undergrad What is the significance of the foci in gravitational orbits?
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Undergrad Which Has A Stronger Gravitational Pull - A Black Hole or Neutron Star?
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High School I saw the 23 Oct 2014 N America partial solar eclipse
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Graduate Why two terms "Dark Energy" and "Dark Matter"
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"Churning galaxy boasts a fiery halo of baby stars"
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