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 HST measures Draco dwarf galaxy over 18 years in DM study
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Undergrad Stable solutions to simplified 2- and 3-body problems?
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Graduate Trying to plot a graph of energy densities for radiation and PBHs
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Undergrad Very bright geo satellite in my night sky?
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Undergrad Diameter of the observable Universe
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Undergrad What is the Possibility of Habitable Planets Around Brown Dwarfs?
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Undergrad Why can't we photograph magnetic lines of force emitted by planetary and beyond objects (like we can for the Sun)?
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Undergrad Is Baryogenesis a Convincing Hypothesis?
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Undergrad Could cosmic rays induce a vacuum decay in the future?
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Undergrad Early Universe massive Black Holes question
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High School Questions about dark matter/energy
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Undergrad Galaxies as systems extended from the solar system
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Graduate Is the Jeffry Scale/Bayes Factor Still Used for Testing Inflationary Models?
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High School Approximately how long does it take for a galaxy to form?
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High School Why is the CNO Cycle considered catalytic in stellar nucleosynthesis?
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High School Is the Universe older than we think?
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High School Discussion on the source or cause of Dark Energy Dark Matter et al
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Undergrad Does Organic Matter Experience Gravity on the Moon?
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High School Is the Sun's Magnetic Field About to Flip?
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High School Question about the Silicon-burning Process beyond iron
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Stargazing How Can You Capture Stunning Moon Photos with a Remote Control?
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High School A question regarding Heliocentric Latitude
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Graduate Very last pulse from a neutron star
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Graduate Should luminosity distance be 0 at z=0?
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Graduate Horndeski: denominator null implies an infinite quantity
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High School Dark Energy: Are We All Missing The Obvious?
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Undergrad Unknown Radio Signal from Space Repeats Every Hour -- Usually
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Undergrad Is the Universe Truly Infinite?
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Undergrad Hydrogen line observation frequency range and space Hydrogen speed?
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High School Asteroid 2024 BX1 entered Earth's atmosphere over Germany 21 Jan 2024
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Stargazing What can I see with 10x50 binoculars in Bortle class 4?
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Undergrad What temperature would 1 keV neutrinos have today?
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Undergrad "Energy is not conserved" vs. energy is conserved: Friedmann Equations
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Undergrad Retro/prograde flyby galaxies and their bar formation
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High School Are some objects in the night sky just older images of other objects?
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Undergrad Questions about paper "How closed is cosmology"
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High School Question about Neon-burning Process
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Undergrad How Does Vera Rubin's Research Support the Existence of Dark Matter in Galaxies?
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Undergrad Observational Astronomy Project Ideas to Show Special Relativity
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Undergrad Brian Cox and the end of the Universe?
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Stargazing My photo of Jupiter (I think)
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Undergrad Latest Findings from DESI Collaboration
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Undergrad I'm slightly confused about the power spectrum of matter
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High School Question About Dark Energy
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Undergrad Speed of light on cosmological scales
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Undergrad Cosmological Scalar Field Density Dilution
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Graduate Matter density crude estimates
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Stargazing Dark matter and its effect on the orbit of stars
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High School Percentage of known energy in the Universe
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Stargazing Documenting the setup of my new telescope
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Undergrad Deriving the Roche limit(d) for body of mass M and satellite m
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Undergrad Questions about Black Holes, Hawking Radiation, and Dark Matter
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High School Pressure on creation of the Universe
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High School Can the "creation" of space in the Universe affect the speed of light?
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Undergrad Can time on elliptical orbit be expressed analytically?
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Undergrad Global properties of the universe
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Undergrad Can there be structures made from neutrinos with angular momentum?
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Undergrad Do Cosmological Models Influence Quantum Field Theory?
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High School History of CMB, prediction of 1 in 100,000?
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Undergrad Light curving around vortex simulating a black hole
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High School U.S. Solar Eclipses - Oct. 14, 2023 (Annular) & Apr. 08, 2024 (Total)
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High School Expansion of the Universe
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Undergrad Determining stellar mass independent of its gravity
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Undergrad Post Big Bang Gravity
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Graduate Why Do Novas Emit Visible Light Despite Nuclear Reactions Producing Gamma Rays?
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High School NASA names asteroid "Hossi" after Sabine Hossenfelder
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Undergrad Why on Earth do we not see older stars close to us?
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High School Solar Wind Particles, - reaching into Earth's magnetic field?
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High School Big Crunch in an infinite, symmetrical, Newtonian universe?
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High School What Are Quasi-Moons and How Do They Orbit Earth and the Sun?
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Undergrad Need help simplifying standard error formula for redshift
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Stargazing 'Devil' comet visible tonight 21.04.24
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High School How Do Radars in Space Prevent Signal Dispersion and Maintain Target Accuracy?
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Stargazing What Could This Unidentified Moving Object in My Seestar S50 Sky Capture Be?
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Undergrad Question about the big bang singularity
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Undergrad Questions about the accelerating Hubble expansion
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Undergrad Sun shade on Earth ground, is it a straight line or a curved line?
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Undergrad Orientation of the Earth, Sun and Solar System in the Milky Way
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Undergrad The linear polarization and brightness of pulsars
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High School Recommendations for International Research Competitions
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Undergrad Where Are the Missing Black Holes in the Milky Way?
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High School How to use the Binary Mass Function for exoplanets?
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Undergrad Has JWST solved the crisis in cosmology?
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Undergrad How fast were distant galaxies moving?
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Undergrad Inflationary vs deflationary phase of Big Bang
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Undergrad Meaning of the distance between galactic objects in GR
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Undergrad Speed of the umbra during eclipse vs rate of the Earth's rotation
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High School What is the actual shape of black holes?
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Undergrad Increase frequency of solar eclipses
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High School Matter-antimatter asymmetry - a simple explanation?
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High School Things to try while watching the solar eclipse
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Undergrad Expanding Universe without dark energy
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Undergrad Can there be slowly-falling accretion disks in black holes?
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High School How black hole Sgr-A* Was Found
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Undergrad Is there an equivalent "redshift" for cosmic rays due to expansion?
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Undergrad The Evolution of Galactic Scale Cosmic Voids
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Graduate What is the maximal comoving distance that a space probe can reach?
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Undergrad Solar anomaly and the Antikythera Mechanism
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Undergrad Vacuum up-tunneling with high-energy events?
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High School TV Series: 3 Body Problem - affects gravitational force?
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