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 Advanced Aliens Are In Happiness Boxes: Why SETI Must Fail
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Undergrad What Were Earth's Rotation Rate and Tilt Before and After the Theia Impact?
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Graduate Would a larger Martian moon create a stronger magnetic field
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High School Cosmic horseshoe is not the lucky beacon
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High School Is the universe expanding at an accelerating rate
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Stargazing How do we know how bright a cepheid variable star is?
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Undergrad Could we detect an intrinsic change in the flow of time?
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Undergrad Simulating Binary Systems with RK4 in C
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High School How could we "reactivate" Mars' magnetic field?
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Stargazing What telescopes are good for seeing planets and galaxies?
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Undergrad Does spacetime have potential energy?
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High School Is supersymmetry a part of string theory
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Graduate Redshift data on stars the same distance from earth
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High School Marginal evidence for cosmic acceleration
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Graduate Take FFT to find time period for eclipsing binaries
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High School Why do areas near the poles experience semidiurnal tides?
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High School Is the Cosmic Horizon the Key to Understanding Holographic Reality?
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Undergrad Where is the matter in a black hole?
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High School Cold spot still baffles scientists
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High School Prediction: A Red Nova May Rival Polaris in 2022
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Undergrad Accelerated expansion and Hubble plot
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High School Observational limit from the super-horizon mode spectrum
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High School Terraforming Venus: Why Nobody Discusses It?
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High School Sean Carroll on Why Does Time Exist at All?
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Undergrad Question about Relatavistic mass
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Undergrad Largest Hard Planet of Gravity 1g we have ever Discovered?
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High School MARVELS Discovery: 1 Giant Planet & 'Failed Star' Found
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High School Gravitationally bound system in an expanding space
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Undergrad Kepler 3rd law for circular orbits
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Undergrad Is BAO a standing or moving wave?
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Undergrad Understanding the curvature parameter k
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Undergrad Why is Mercury Visible at Night?
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Graduate How is the red-shift of CMB obtained?
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Undergrad So we've found the missing "dark matter"?
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High School Do Stars Experience Precession Like Our Sun?
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High School Need confirmation of planetary distances
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Graduate What is orientation of a needle shaped spacecraft?
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Undergrad How is the timing of the big bang known
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High School Line absorption spectrum and stars
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Graduate What if i do not go into orbit but close in on a langrange p
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Undergrad How to draw figures and diagrams?
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Insights Is the Universe a Black Hole? - Comments
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Undergrad Modeling a Binary Asteroid System Around the Sun
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Undergrad Can dark matter explain Tully-Fisher relation & new paper
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High School Nobel laureate perspective on the history, status and future of GR
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Undergrad Database of Galaxies and their parameters
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Stargazing Advanced Astrophotography - Comments
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Stargazing The James Webb Space Telescope construction
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High School Is a lunar space elevator a realistic proposition?
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High School What do scientists mean by 'Nothing'?
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Undergrad Open access papers in JGR-Planets
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Undergrad How can Andromeda collide with the Milky Way?
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High School Uranus May Have Two Dark Unseen Moons
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Undergrad No Boundary Proposal: Overview, Criticisms & Probes
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High School The aliens are silent because they are dead
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High School What was the curvature of the early universe?
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Undergrad Why does this redshift v. light travel time equation work?
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High School The news media on 2 trillion galaxies: Confused, or am I?
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Undergrad Why don't any stars "look" red? red shift
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Stargazing Intermediate Astrophotography - Comments
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Undergrad How to Understand the Primordial Power Spectrum in TASI Lectures on Inflation?
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Undergrad How did Tycho Brahe measure time?
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High School Why isn't Dark Matter involved in Weak Nuclear reactions during BBN?
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Graduate How is the duration of BBN calculated?
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High School The observed spatial distribution of matter
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High School Before Big Bang: What Surrounds the Singularity?
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Undergrad Solar System Origins: Angular Momentum Problem?
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Stargazing Seeing Uranus - Two Nights of Celestial Wonders
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Graduate Finding an exoplanet via its magnetosphere's effect on starlight?
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Stargazing Introduction to Astrophotography - Comments
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Graduate Is the Universe Random or Chaotic?
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High School Found: The Least Luminous Galaxy Ever Seen
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High School Gravitational wave signal duration
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Stargazing How can the telescopes take photos of distant galaxies?
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High School Where is the Void? Universe Big Bang & Expansion
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Graduate Types and Common Names of NGC/IC objects
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Graduate Sir Roger Penrose: Challenging Modern Physics Theories
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Undergrad CMB-S4 Science Book: First Edition | The Universe's Secrets
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High School Gravity: Is it Spacetime or Mater-Dependent?
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Stargazing How to build an optical telescope for research?
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High School Black Holes and The End of Spacetime
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High School What percentage of the universe do we know
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Undergrad What Causes Distinct Absorption Bands in the Sun's Spectrum During Sunset?
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High School Space Finite? Inconceivable - Thoughts?
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Graduate How do quantum fluctuations become gravity wells?
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High School Unusual Exoplanet Discovery Using Star Pulsations: KIC 7917485b
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Undergrad Plotting the orbits of the planets
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Undergrad What computer science would you need for astrophysics?
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High School Entropy change during the formation and death of stars
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Undergrad Gravitational acceleration and the baryon distribution
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High School Is Spacetime Actually a Superfluid?
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Undergrad Light fluctuations and finding exoplanets
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Undergrad Would Heat Death overcome Strong Nuclear Force?
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High School Combine a horizon line with expansion
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Undergrad Is something pulling our universe?
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High School Shapes and gravitational radiation
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Undergrad Gravitating particles and entropy
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High School Coordinated galactic bangs instead of big bang
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Undergrad How would dark matter aggregate?
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High School Unsolved Mystery: Where Do These X-Rays Come From?
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