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 Multiverse and observational evidence?
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High School Spatial Expansion -- Coincidence?
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High School What would the planets look like in real life?
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Undergrad Mining the Universe's expansion?
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Graduate On the origin and the evolution of information in the Universe
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Undergrad Receding movement of a stopped object in an accelerating universe?
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Undergrad Lectures on the Varying fine structure constant
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Undergrad Cosmic strings increasing internal energy?
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Undergrad How accurate is the distance to M4 and its stars according to different sources?
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High School Amazing Rings: Intersecting Stars Create Spectacular Gas Rings
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Graduate Is the FLRW Metric a Valid Approximation for Our Universe on Large Scales?
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High School The value of the standard acceleration due to Earth's gravity
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Graduate Non-minimally coupled inflation — expansion
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Undergrad What is the temperature dependence of the NIRCam sensor's responsivity?
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Graduate A pair of interesting papers: have counterarguments been published?
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High School Understanding the Expansion of Space: Galaxies Moving Away and Proving Expansion
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Undergrad How Does Space Expansion Affect the Velocity of Galaxies?
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High School Could a black hole just be a planet?
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Undergrad Distant Galaxy study, dark matter and the CMBR
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High School Celestial mechanics: Why is my planet orbiting faster and faster?
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Undergrad What Equation Determines the Cosmic Event Horizon Distance?
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High School Could the source of dark energy be our parent black hole feeding?
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Undergrad Upper limit of relativistic spin?
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Undergrad Can we see light pollution from space?
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Undergrad Does all infrared get detected as heat?
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High School What does relativity say about wormholes?
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Undergrad Gas Density of Lunar Crater Rims: Comet vs. Asteroid Impacts
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Undergrad Question about the William Herschel Telescope's new "Weave" device
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Undergrad What is the significance of slow-roll inflation in cosmology?
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Undergrad JWST breaks another Redshift record
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High School Could a Galaxy Older than 13.8 Billion Years Redefine Cosmology?
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Graduate Is the Universe Finite, or Is It Infinite?
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Undergrad Is the Bullet Cluster Evidence for or Against Dark Matter?
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Undergrad Help me on the timeline of star formation in the early Universe
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Stargazing How can we see the ISS at 200 miles away with the naked eye?
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Undergrad Voyager I and Voyager II informative video
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Undergrad Starlink and gaining energy from orbiting
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Undergrad Could a bubble shield at L1 combat global warming?
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High School Effect of JWST mirror damage on final images
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Undergrad What do high-mass X-ray binaries, or HMXBs, tell us?
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Undergrad How to calculate an unknown planet's orbital period?
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Undergrad A glitch in Jorrie’s Cosmo-Calculator?
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Undergrad Paradox: How can we look back at the Big Bang?
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High School What Is the Information That Cannot Escape a Black Hole?
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Undergrad Solar system simulation errors
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Undergrad Help with Sunrise & Sunset formulas please
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Undergrad Amount of black hole entropy inside the Universe?
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High School Question about deep space pictures
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Undergrad Question re flat infinite universe with a preferred direction
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Undergrad What is the density of the Carina Nebula?
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Undergrad Why is the observed local region of space flat?
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Undergrad A new solution to Olbers' Paradox?
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Undergrad Is the eccentricity of the lunar orbit constant?
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Undergrad Confused by this armillary sphere in Australia
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High School Temporal differences across a galaxy?
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Undergrad Mass distribution in a celestial system
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Undergrad Earth's orbit not perfect ellipse
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Undergrad SpaceX says 5G expansion would make Starlink 'unusable' for most Americans
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Undergrad Reheating and the horizon problem - chicken and egg?
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Graduate From polar coordinates to heliocentric ecliptic coordinates
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Graduate Can the Universe's Expansion Allow Us to Escape Its Event Horizon?
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High School Big Bang Question -- How was the first matter formed?
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Graduate How are time and distance measured in cosmology?
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Graduate What is the total mass-energy of the universe?
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Undergrad The curvature of space and curvature of spacetime
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High School Can nuclear bomb(s) change trajectory of small black hole?
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Undergrad Bubble universes and physical constants
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High School SOFIA IR Observatory in the Southern Sky
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Undergrad Why are Saturn's rings in its equatorial plane?
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High School Mars Probe gets Windows 98 Update, after 19 years
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Undergrad Some questions about Cosmic Microwave Background radiation
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High School Where can I find information about Population III stars?
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Undergrad I have an error in integrating to calculate the age of the Universe
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High School Is it possible for a giant star to have a black hole inside it?
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Undergrad The gravitational center of the Earth
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Undergrad How to find RAAN and argument of perigee for a satellite?
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High School How often do you re-acquire dark and bias frames?
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Undergrad How does the symbol Λ cosmological constant relate to Ω_Λ or ρ_Λ?
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High School Is Stellina the Ultimate Telescope for Amateur Astronomers?
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Undergrad Voyager Spacecraft beginning to Power Down
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Undergrad Some questions about Cosmic Inflation
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High School Where Can I Find Accurate Planetary Event Data for an Astronomy Course?
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Undergrad Are there types of spacetime where no symmetries are valid?
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High School Has there been no update to Allen's Astrophysical Quantities since 1999?
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Undergrad Seeking understanding regarding Ω_b, Ω_c, and Ω_m
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High School Evolution of planetary system around a white dwarf
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Undergrad What is a typical mass density for inter-galactic gas in a cluster?
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High School How much energy does our Universe have?
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Undergrad Postulating a minimum gravitational field strength
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Graduate What is a Bern model in planetary population synthesis?
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Undergrad Questions about Negative Pressure and Vacuum Energy
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Undergrad If the Universe had a different size, would physics change?
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Undergrad Is the CPT-Symmetric Universe Theory the Key to Solving the Antimatter Mystery?
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Undergrad Alexander Vilenkin and energy of a closed universe
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High School Sun contains more oxygen, silicon and neon than previously thought
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Undergrad Seeking reference for math related to the age of Recombination
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Undergrad Lateral offset from a centered star as measured at the focal plane
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Undergrad Magnetar Mystery: How Do Neutrons Generate a Magnetic Field?
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High School Derivation for Aphelion and Perihelion Distances
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Undergrad What is the current status of Voyager 1's attitude and control system?
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