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 Question about Tong's cosmology lecture notes eqn. 1.19
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Stargazing Merger of two black holes (video)
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High School Brightness of different layers of the Sun
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Graduate Understanding NOAA and Naval Observatory's Solar Calculations
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High School Atmospheric refraction and "rainbow"
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High School Analogue Black Holes: Disposal?
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Undergrad How big a lunar radio telescope to detect Earth-like signals?
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High School Could you build a container to isolate cosmic radiation?
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High School Question: Orbital mechanics of a binary star system
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Stargazing Meteorite crash recorded on video in Canada
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Graduate What does it mean to model the distribution of galaxies as cosmic dust?
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Undergrad What affects light near black holes and stars?
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High School How do we know if a distant galaxy is matter or anti-matter?
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High School More scope refurbishments or start new?
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Stargazing How Did You Capture the Mars Occultation? Share Your Photos Here!
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High School Questions about the Eddington Limit and Super - Eddington black holes
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Undergrad Nature paper on Moon's initial evolution - Tidally driven remelting
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Undergrad The Heavier Elements: A Question About Their Abundance
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Undergrad Moon phase ruins my Stargazing!
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Graduate Models without dark energy
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High School Help w/ repairing/refurbishing an equatorial mount
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High School Does my theory about black holes make sense ?
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Undergrad Expansion of a star to become a red giant
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High School Considering a budget observatory
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Graduate Is there a stretching of the light curves of supernovae 1a?
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Undergrad 3 questions about a paper on density fluctuations in the Universe
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Undergrad How to graph Earth's path?
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High School Evolution of the Universe in reverse
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Undergrad Possibility of multiple planets sharing the same orbit?
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High School What If We Could See the Past by Placing a Mirror on the Sun?
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High School Popular physics - The Nebra disk
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High School Can a thunderstorm affect a satellite in low earth orbit?
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Undergrad Is this the correct representation for showing the direction of a star on CMD?
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Graduate Where to find black hole datasets
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Graduate XSPEC Composite Model Partial Flux Calculations
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Graduate Spectral Data Availibility
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Graduate Interpretation of an anticorrelation between 𝐻0 and log10(𝜔𝐵𝐷)
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High School Can nature do this in the night sky?
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Stargazing Is My Heavy, Slightly Magnetic Rock with Green Glass Particles a Meteorite?
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Undergrad Does light bend around black holes?
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Undergrad The Boundary of the Observable Universe
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Undergrad Do particles leave behind an image when crossing cosmo event horizon?
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High School Predicting frequency of Earthlike planets and systems
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Undergrad How would the laws of thermodynamics change in a contracting universe?
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High School Cosmological Redshift in Simulated Universe
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High School Neutron star 4U 1820-30 spins at 716 revolutions per second
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Graduate Form of energy at time of big bang
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Undergrad New Developments In The Search For Planet X
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High School Looking for Axions in Neutron Stars
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Undergrad Right ascension and Declination calculations
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Undergrad Why do we still see the CMB today?
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Graduate Black hole thermodynamics and accelerated expansion
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Undergrad The brightness and linear polarization of pulsars
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Undergrad Two-dimensional negative curvature space
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High School Redshifts of nearby galaxies
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High School Optimizing Exposure Times: Balancing Efficiency and Image Quality
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High School Strange cosmic particles in my detector
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Undergrad The Universe is expanding with acceleration
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High School Variation of Apparent Luminosity with Distance
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High School The Earth is upgrading with a second moon
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Undergrad Distance at redshift z=0.666
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Graduate Dark matter is running out of places to hide!
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High School Galactic Sheets and Voids
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Undergrad Bose-Einstein and Fermionic condensates in space?
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High School Asteroid 2024 RW1 - entered Earth's atmosphere over Luzon, Philippines
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High School How can an infinite universe expand?
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Undergrad What if the early expansion of the Universe was not so rapid?
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Undergrad Does the amount of hidden mass remain constant?
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Undergrad Rotation curve of a gas disk in an elliptical galaxy
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Graduate Looking for information about spectroscopy isotopes and stellar formation
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High School Do Fictional Worlds Exist in the Multiverse?
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High School Questions about a paper on reconciling JWST and HST data
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Undergrad How we are in a matter dominated universe (without antimatter annihilation)
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Undergrad J0524-0336, surprisingly high Li concentration
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Undergrad Can there be free electrons in interstellar gas?
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Graduate Does modified gravity somehow explain galaxies that don't need it?
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Undergrad Regarding the accuracy of the description of a pulsar in a 1977 paper
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Undergrad Wow! signal could be from interstellar hydrogen clouds
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Undergrad Comet A117uUD Goes Interstellar after Encountering Saturn in 2022
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Undergrad Toward the spectral index in slow roll
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Undergrad Density fluctuations in a homogeneous linearly expanding universe?
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High School Will we ever communicate with extraterrestial life in a reasonable time frame?
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Undergrad What is the reason for density perturbations in the CMB?
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High School What Are the Mysterious Zig Zagging 'Stars' in the Night Sky?
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Undergrad Question on halos of matter made from massive and stable particles?
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High School Temperature difference between Venus and Mercury
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High School Asteroid Dimorphous easier to move because it's made up of rubble?
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Graduate N-Body inputs from Keplerian Orbits
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Graduate Efficient cone searches with Healpix-alchemy
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Graduate Celestial objects - older than the CMB
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High School Matter/Anti-Matter in a Vacuum
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Undergrad What Factors Create the Windiest Exoplanets?
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High School Big Bang as the Collapse of a Wave Function
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Undergrad Any Galaxy (Milky-way) based coordinate systems?
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High School Expected Earth-relative velocity of interstellar particles
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High School Interstellar navigation to Proxima B with an unmanned probe
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Undergrad Galaxy collision separates dark matter from regular matter
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Stargazing Any Heliocentric planetrorium software or site?
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Stargazing Some photos of Antares and Sigma Sagittarii (Nunki)
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Undergrad Shell structure topological defects as substitute for dark matter
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