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 Energy-momentum tensor as energy density
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Undergrad Are orbital resonances constructive or destructive?
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High School Observing Orbital Mechanics from the 2nd Focus of Earth's Orbit
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Undergrad Magnetism and Gravity Discussion/Questions
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Undergrad Universe re-collapse and time reversal
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High School Why was the Sun's output not as intense in the past?
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Undergrad Finding Exoplanets: How Astronomers Do It
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High School Spacetime: The cause of matter?
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Undergrad Infinite space in a finite bubble, in a Tegmark Level 2 multiverse?
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High School How can we watch BHs collide in a finite time?
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High School Star visible for longest time from Earth
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Undergrad Can Relativistic Matter Exist At Absolute Zero? - Explained
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Undergrad How do we know that red-shift is caused by expansion?
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Stargazing Is the Hubble Space Telescope Dead?
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Graduate How do we differentiate the K-corona from the F-corona?
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Graduate How Can I Filter Known Globular Clusters in SDSS Data?
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Graduate NASA’s InSight Mission Reveals Internal Structure of Mars
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High School Do emission nebula glow because of ionised or excited electrons?
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Undergrad ##\Lambda##CDM: Evolution of the population of galaxies
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Undergrad Black Hole to Other Universe: Violation of 1st Law?
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Graduate Is the CMBR interpretation for dark matter a fudge?
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Undergrad Questions about Density Parameter and Critical Density
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Undergrad Red-Shifting vs. Luminosity Question
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High School Sun-Earth Encounter: Acceleration, Roche Limit, Rotation & More
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Stargazing Could Elon Musk's Starlink orbitals piggyback telescopes?
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High School The Impact of Tidal Force on a Star's Magnetic Field and Supernova
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High School Does Gravitational Time Dilation Affect the Speed of Light in Outer Space?
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Graduate Relationship between energy density and cosmological constant
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Graduate Did the Universe Begin as Pure Energy?
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High School Biggest asteroid to pass Earth in 2021
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Undergrad Rotation curve with neutral hydrogen and dark matter
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Undergrad Particle and Event Horizons in the ΛCDM Model
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High School Questions about dark matter, matter and elements
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Undergrad The Acceleration and the density of galaxies
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High School Accelerating Universe Expansion: Age & Hubble Constant
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High School Betelgeuse unusual dimming - what's up?
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Undergrad Slow-roll Inflation and Horizon Problem
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High School Light Leaving Earth-Observer's View of Events in Time
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Undergrad Dimensions of Cosmic Scale Factor ##a(t)##
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Graduate Relation between Matter Power spectrum and Angular power spectrum
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Undergrad Why are emission spectra of stars rarely shown?
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High School Why can we only see one side of the moon?
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Undergrad What is the average annual accumulation of cosmic dust on Earth?
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High School Looking for Simulations of Exoplanets
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Graduate Expression of the mean and variance of spectroscopic Shot Noise
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High School What happens to time as space is expanding?
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Undergrad Temperature of the Universe based on the ΛCDM Model
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Undergrad Can a Homogeneous Universe Avoid a Big Crunch?
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Undergrad Implications if New Dark Matter Maps are Correct?
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High School Cosmological constant for the Universe's expansion
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Undergrad If Jupiter had a 5th large moon until "recently", would we know?
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Graduate New Dark Energy Map Challenges Einstein's Theory
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Undergrad Andromeda vs. Milky Way galaxies
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Undergrad What is theoretically the heaviest isotope that the R-process could produce?
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Graduate Cosmological gravitational waves
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Undergrad Planetary orbits - the 2-body problem
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High School Seeing a half Moon - where is the Sun?
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Stargazing Lightning ball - me to analyze this rare video
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Undergrad FRBs (Fast Radio Bursts) -- New clues of their location and origin
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High School Could an Extraterrestrial Object Near Earth Disrupt Satellites?
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Undergrad New H0LiCOW result: Hubble constant is 73.3 +1.7-1.8 km/(s*Mpc)
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Graduate Fourier transform and Cosmic variance - a few precisions
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High School Feasibility of multiple "big bangs"
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Stargazing Macroscopic Dark Matter Revealed By Lightning
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Undergrad Dark energy is intrinsic to the space itself
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Graduate Polling for estimates of probability our universe is infinite
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Undergrad Black Hole Diameter: Is It Finite or Infinite?
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Undergrad Freshly Made Plutonium From Outer Space Found On Ocean Floor
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High School The Fate of the Universe -- Expansion or Collapse?
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Undergrad What Is the Difference Between Spacetime Curvature and Spatial Curvature?
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Insights Do Black Holes Really Exist? - Comments
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Undergrad Proton decay at the end of the Universe
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Undergrad How fast must Voyager travel to leave the solar system?
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High School Why Do We See Darkness in a Universe Full of Stars?
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Undergrad The Hubble constant − constant in what way?
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Undergrad How long would it take the Universe to generate an Earth-like chemistry?
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Undergrad Mass, Distance & Early Universe: Is It Mere Coincidence?
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Undergrad Spatial flatness and cosmological constant
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Graduate What Do Planck 2015 Results Reveal About Power Law Potential Models?
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Graduate Question about extragalactic stellar motion
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Undergrad Are some cosmic rays iron nuclei?
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Undergrad Changing curvature as a universe evolves
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Undergrad What happens to the material not involved in the core collapse of a supernova?
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High School Vertical lift question (Lift a roof from beneath with limited space)
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Undergrad Some questions about baryogenesis
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High School Mass and Surface Gravity of a Dyson Sphere
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Stargazing Roberto's Indonesian Punggur Meteorite: My 2021 Collection Addition
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Undergrad Quantum Astronomy - well sort-of
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Graduate Angular power spectrum dependence in redshift z and k
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High School How Do Black Hole Animations Capture Optical Effects?
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Undergrad How do I properly plot the solar spectrum and handle the flux of Arcturus?
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Undergrad Are all the celestial systems in the universe on a big plate?
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Undergrad Is the Isotropic Universe Truly Centerless?
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Undergrad Can Future Civilizations Use Dyson Spheres to Survive a Red Giant Sun?
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High School Is Colonizing White Dwarf Systems Feasible for Interstellar Travelers?
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High School Jupiter's pole storms - potential relation?
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How Black Holes Work: The Onion Explains
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Graduate Do relativistic effects make the age of the universe moot?
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High School Question about "our observed universe"
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Graduate Looking for sources of information on Black Holes
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