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 Why aren't Gravitational waves factored in to inflation formulas?
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Undergrad What are the Cosmological monopole and dipole?
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Undergrad Composition of Jupiter: Ices, Cores & Outer Gas Layers
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Undergrad The definition of volume inside black hole?
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High School Stars massive enough to evolve into black holes
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High School Name of projection to firmamentum (celestial sphere)
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High School Navigating To Another Star System
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High School No way to catch up with galaxies currently receding at >c?
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Graduate COG calculation of diffracted spots on a camera
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Graduate Can Background Radiation Serve as a New Coordinate System in Astronomy?
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Undergrad Stromgren photometric data in Vizier
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Undergrad Simulation debugging for Apollo Lunar Landing
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Undergrad Encircled energy for different aperture shapes (circle, triangle, square)
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High School Question re Webb telescope at L2
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High School Visit to Hayden Planaterium -- The projector is gone?
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Undergrad Issue with Stellarium: transit of Venus (find the parallax)
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Stargazing Better than Mars Colonization in many aspects.
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Undergrad How well do cosmological models explain the observed µ vs. z data?
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Stargazing Star appearing to move ping pong like rapidly
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Graduate Obtaining the noise level of a camera
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Undergrad Confused about declination, elevation & altitude
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Stargazing Does an Analemma visualize the Earth's actual orbit around the sun?
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Undergrad What's left to see of the early Universe?
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High School Radiation Levels at Earth's Poles
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Undergrad Inflation and size of the Universe
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Undergrad Collision between the Milky Way and Andromeda and Redshift
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Stargazing Troubleshooting My Orion 130 Reflector
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Undergrad What Are the Origins of the Universe?
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Undergrad Cosmological principle about space and time
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High School Is an infinite universe compatible with cyclic models?
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High School Acceleration of time due to entropy
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High School Confused About the Source of CMB Photons: Two Possibilities
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Undergrad About the relation between number of sidereal and solar days
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High School According to current physics, is vacuum still something or nothing?
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High School How long it takes the Earth to fall halfway to the Sun--ellipse method
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Undergrad Curvature Index in Flat Universe with Cosmological Constant?
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High School Delta-v from Lagrange points to lunar surface?
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Undergrad So I wrote a book on cosmology....
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Undergrad Assumptions for blackbody spectra vs. emission spectra vs. absorption spectra
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Stargazing Calculating the Resolving power of a Telescope
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Undergrad On the assumption of an infinite universe
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Undergrad Can someone explain Quasi-steady-state cosmology to me?
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Undergrad What is the acceleration of the expansion of the Universe?
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High School Is there a way of creating placemarks in Stellarium?
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Graduate Analemma layout and proportions on a sundial
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Graduate Add factor Δℓ or Δℓ^2 in the variance for integrated Shot noise
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Undergrad Newton's 3rd law and ether in space
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High School Are there more theories about the start of our Universe?
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High School Question about the solar system and gravitational forces
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Undergrad The CMB drag on an object moving through space
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Undergrad Is acceleration a more absolute/fundamental quantity in the universe?
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Undergrad What does Causality really mean?
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Undergrad Energy conservation in an expanding universe
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Graduate Introduction of a factor Δℓ when summing equal distants 𝐶ℓ
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Undergrad Planetary Formation: Could Collisions Explain Our Solar System?
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Undergrad Is There Evidence to Suggest Our Universe is Anisotropic?
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High School Pressure under the ice of Europa?
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High School Can we measure acceleration of galaxies and stars?
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Undergrad What Are These Mysterious Objects Spotted Near Orion?
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Undergrad Evidence for existence of a 9th Planet in the solar system
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Graduate Cl's : sum into a chi^2 when we have a sum of chi^2
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High School Why does MOND fit rotation curves so exactly?
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Undergrad Can magnetic fields explain anomalous galaxy rotation curves?
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Undergrad Is the existence of a Dyson Sphere impossible?
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Undergrad Dark matter + gravity is 'right', or our understanding of gravity is wrong?
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Undergrad Could Titan Be Our Next Home for Colonization?
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Undergrad Is Dark Matter Composed of Low-Mass Particles?
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High School Traveling to alternate universes
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Graduate Analytical expression of Cosmic Variance - Poisson distribution?
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Undergrad Does a photon travel freely through the CMB photon gas?
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Undergrad Is it time to take the 'bang' out of the Big Bang?
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Undergrad What atoms are we made of, how much is from the big bang?
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Undergrad Shouldn't the Big bang be physically impossible?
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Undergrad Could dark matter consist of primordial black holes?
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High School Please help in explaining 'we are not the center of the Universe'
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Undergrad Did cosmic inflation happen everywhere in the Universe?
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High School Question on paper: Inflationary spacetimes are not past-complete
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Undergrad Acceleration of Universe Expansion: 1/r2
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Undergrad What happened to the range of frequencies after recombination?
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Undergrad Orbital distance increase during the white dwarf phase of the Sun
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High School Definition of Stellar Parallax from Alonso and Finn Volume 1
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Undergrad Black holes and relation to creation
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High School How Sensitive Must SETI Arrays Be to Detect Extraterrestrial Signals?
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Undergrad Does the CMB reference frame violate the Cosmological Principle?
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High School Can particles interact without a mass?
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High School Do Atoms Expand with the Universe?
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Undergrad Why does particle physics predict cosmo constant is 10^120 too big?
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Undergrad N-body simulation of high or low-mass dark matter particles
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Undergrad Dark matter and structure formation
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Undergrad An apparently obscure question re dark matter
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Undergrad Is the supply of the observable CMB radiation limited?
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Undergrad Dark Sky Parks -- coming to a park near you
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Graduate Radius of the Sun: Can We Accurately Predict It Through Theoretical Models?
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High School What is the Universe expanding into?
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High School Some visuals for Size of Solar System, Galaxy, Universe
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Undergrad (See image) At what distance does the temperature of the Corona decline?
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Undergrad What would be the geological consequences of a "big crunch"?
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Graduate Single photon avalanche detector (SPAD) difficulties with photometer
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Undergrad What would be the geological events during a "big slurp"?
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Undergrad Granules On The Sun: Photosphere Or Convection Zone?
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