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.
Graduate Could a universal Oort cloud structure cause expansive acceleration?
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Graduate What Is a Black Hole Firewall?
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Graduate Could dark energy and expansion of space be just a topological effect?
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Graduate When talking cosmology what exactly is a manifold, is there any
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Graduate Cosmic Distance Ladder: Advancing Physics of Cosmic Distances
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Graduate What are the objectives of the GAIA mission and satellite?
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Graduate Philosophical: Is the universe a type of Turing machine?
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Discover the Fascinating Olber's Paradox in This Cartoon Cosmology Video
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Graduate Questioning the Expansion theory
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Undergrad Space: Is It an Idea or Physical Reality?
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Graduate Expansion of the universe and the speed of light
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Graduate Gravity and Acceleration on a 50,000 km Space Elevator
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High School Simple Question about the Solar System/Planetary Systems
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Undergrad Can Slow Space Travel Overcome the Speed Barrier in Vacuum Flight?
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Why a space before a punctuation mark?
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Graduate How Are Elements Beyond Iron Created in Stars?
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High School Duke University Astronomy 101 Online Course
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Undergrad Simple Beginner Dark Matter Question
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Graduate Comparing Large Stars and Black Holes: Understanding Event Horizons
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Undergrad Available Astronomy Research Topics?
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Graduate Why cannot the universe have net angular momentum?
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Stargazing Bought Orion AstroView 90mm, good?
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Graduate Dark matter solution: not receiving all the light?
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Undergrad Quick Question about the Doppler Effect
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Graduate Naive question regarding black holes.
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Graduate Black hole has a partiuclar fixed volume
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Undergrad How Can I Estimate Local Sidereal Time in My Head?
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Undergrad Solar system space dust avg density[kg/m^3]
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Graduate After watching the Stephen Hawking Series
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Undergrad Question Gravity: Explaining Planetary Motion & Hailey's Comet
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Graduate What Is the Relationship Between Time and Space in the Universe?
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Undergrad A basic question on gravity from a novice
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High School Radio communication from the galaxy's far side?
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Undergrad What Would Happen If Mars Had a Higher Density and Maintained Its Radius?
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Graduate What is the Probability of Multiple Universes?
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Graduate Light from MACS 1149-JD implausible
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Graduate Omega being less than one in a flat Universe?
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Graduate Do Tidal Forces in Black Holes Affect Matter at the Quantum Level?
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Graduate Gravitational binding energy of some stuff
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Undergrad Is Everything Shrinking Instead of Space Expanding in the Big Bang Theory?
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Graduate Is the CMBR a relic from the big bang or an image from background galaxies?
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Graduate Number of Voids in the (observable) Universe
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Undergrad Is the only evidence for an expanding universe the doppler Red Shift?
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Undergrad Which Observational Project sounds funner/easier?
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High School Is Jupiter Brighter When Far from Venus?
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Undergrad The importance of atmospheres for the planetary temperature
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Graduate 3-dimensional implications of a black hole
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Undergrad Figuring Out Mysterious Meteorite: Speed, Trajectory & More
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Can Light Be Slowed or Even Stopped?
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Undergrad Perpendicular velocity of planets
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Graduate What Is the Universe Expanding Into?
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High School Gravitational Pull: Sun vs. Earth's on Moon
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Feynman checkerboard as a model of discrete space-time
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Graduate Would Cosmic Expansion Break a Tether Between Galaxies?
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Graduate Gravitational Lensing and Redshift
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Graduate Does the holographic principle remove the need for dark matter
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Graduate How inflation solves the horizon problem
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Graduate Is Dark Matter Uniformly Distributed Locally and in Distant Galaxies?
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Graduate Minimum Satellite Period problem
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Graduate Would motion explain the missing 'dark matter'?
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Graduate Effect of gravitational tides on the moon
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Undergrad Understanding Elliptical Orbits: Foci, Center, Barycenter, and Mass Relationship
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Graduate Dark Matter: Understanding Its Nature & Impact on Stars, Planets
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Graduate Why is the age of the Universe the reciprocal of the Hubble constant?
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Undergrad Is the Sun Really Older Due to Relativity?
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Undergrad Could Dark Energy be Dark Matter cooling?
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Graduate Could a cosmo tabulator give hands-on experience with cosmic Event Horizon?
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Graduate Can We Pull a Metal Ball Out of a Black Hole With a Steel Cable?
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Undergrad Stellar Nebulae and angular momentum
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Graduate Is the Decaying Vacuum Model a Complete Description of Cosmic Expansion?
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High School Black holes and gravity basic questions
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Graduate Unraveling the Mystery of Black Holes: The Paradox of Singularity and Infinity
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Graduate Can Super Mercurys Support Life and Sustainable Plate Tectonics?
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Undergrad Can we give an analogy for nucleus to sun and electrons to planets
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Graduate Space Smoothness: Virtual Particle Effects on Photon Paths
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High School Magellanic Clouds — two irregular dwarf galaxies in the Milky Way
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Undergrad Horizontal + Celestial Coordinates to Geographic Coordinates
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Is the sun visible if you're standing on the moon?
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Graduate Gravity and the expanding universe
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Undergrad Why does the cosmic microwave background make a noise
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Undergrad How to get longitude from Two Line Element (TLE)
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Graduate AIPS: flagging bad data, calibration, etc
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Graduate Brian Powell's latest paper: Scalar runnings
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Undergrad .Understanding Stress on Space Elevator
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Undergrad What the minimum mass for a habitable exoplanet or moon?
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Graduate Does CMBR Cooling Mirror Black Body Radiation Processes?
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Undergrad A few questions about black holes
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Undergrad What would happen if someone was sucked into a black hole?
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Undergrad Hubble's law and the age of the universe
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Undergrad Where do the heaviest elements come from?
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Undergrad How can the universe be moving faster?
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Graduate Fundamental Existence Of Matter/Energy
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Undergrad Cosmological models and begining and ending of universe
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Peer-reviewed case study of how an ideal universe would work
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Undergrad Do Black Holes Work Like a Sucked-Out Fire?
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Undergrad Can the merging of white dwarfs explain Type Ia supernovae explosions?
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Graduate Why are we so sure the universe existed in a point 13.7 billion years ago?
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Undergrad Relating Newton's universal law of gravitation with Kepler's 3rd law
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Undergrad Effect of Telescope Aperture Size on Spectrometer Resolution
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Graduate Non-expanding solution to redshift observations
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