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 A question from a paper on perturbation theory
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High School Terminology for motion in the solar system, ecliptic maybe?
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Stargazing Eye protection while watching a total solar eclipse
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Graduate Friedmann-Lemaitre-Robertson-Walker model
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Undergrad Atmospheric escape parametre statistics
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Undergrad Stellar evolution path and Regression line
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Undergrad How Does the Size of Neutron Stars Compare to Black Holes?
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Graduate Atmospheric Density Required for Mercury´s Polar Regions to be Warm?
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Undergrad How Can Measured Satellite Magnitudes Be Converted to Radiant Intensity?
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Undergrad Is the Sun's photosphere fluorescent?
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High School Layman's summary of water telescope experiments
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High School Photographing a solar eclipse with a smartphone (safely)
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High School Why isn't there an effort to name non-stellar celestial objects?
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High School Rock Found in Field Turns Out to Be 4.6GY Old Meteorite
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Undergrad Fourier transform of the density fluctuation
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Graduate How do I determine the surface magnitude of a galaxy from a SED?
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Undergrad What is the Freeze-Out Temperature of WIMP Particles?
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Undergrad What are the Dynamics and Impacts of a Type II Supernova?
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Undergrad Why Does Spectral Line Darkening Occur Despite Photon Re-Emission?
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High School How Is Solar Wind Temperature Measured?
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High School What is the difference between a rocky planet's core and the Sun's core
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Undergrad Adding more meteorites to my collection
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High School Can the force of gravity overcome the Planck force?
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Undergrad Is Gravitational Red-Blue Shift Dismissed in Cosmic Observations?
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High School Do we 100% know what the geometry of the Universe is?
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Undergrad Do the Sachs-Wolfe and Rees-Sciama Effects Influence Matter?
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High School Can Spacetime be Torn According to Quantum Theory of Gravity?
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Undergrad Relationship Between Expansion and Curvature in the Universe
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Undergrad How Does Curvature Density Parameter Affect Universe Flatness?
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High School Could Dark Energy be an (unknown) dark force acting at great distances?
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High School How did ancient astronomers track changes in positions of stars?
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High School Question about Hawking Radiation and Iron Stars
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High School Did I Capture Sunspots in My Summer Sunset Timelapse?
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Undergrad Boltzmann equation for annihilation
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Sample and Return of Asteroid Bennu - live on Oct 20, 2020 at 1720 GMT
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Help Identifying rock or meteorites
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Undergrad Separation angle between pulsars detecting Gravitational Waves
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Stargazing What is an arcsec and how do I convert it into AU or m?
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Undergrad Voids, dark energy and tidal forces...?
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High School Where does the original singularity get its energy from?
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High School What Does the Astro Physics Equation from Lewis Season 8 Episode 2 Mean?
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Undergrad Why Does Gravity Remain when Star Mass Dissipates?
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Graduate Could Re-Analyzing Redshifts Reveal New Physics?
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Stargazing Is There an Unidentified Object Near the Horsehead Nebula?
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High School Cosmic Graviton Background and Primordial Gravitational Waves
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High School What Medium Does Light Travel Through in Space?
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High School Is the barycentre of the Pluto - Charon system also the L1 point?
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High School Debunking Bat and Skull Nebulae fakery
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Graduate Why Is the Hamiltonian Approach Preferred for the Restricted Three Body Problem?
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Undergrad Plotting the orbits of the planets from Ephemeris data
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High School Observable universe and overlapping spheres
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High School How would physics change if Planet 9 were a primordial black hole?
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High School Celestial plane orientation to the galactic core
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Undergrad Help identifying this Tumbling object in a night sky photo from Namibia
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High School Dark matter and extreme gravitational regimes
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Undergrad On Quanta article on the recent tensions of cosmology
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Undergrad Calculating the End of the Universe Using Standard Deviation Statistics
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Undergrad Why Do Stars in Binary Systems Assume a Teardrop Shape?
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Undergrad Mass in an expanding or static spherical distribution of matter
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High School Is perpetual motion a forbidden topic in the scientific community?
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Undergrad Questions about the Location of the Big Bang and the Age of the Universe
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High School Comoving distance constant with increasing redshift?
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Undergrad How does flux density scale with redshift?
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Graduate Numerical evolution of Einstein-Boltzmann equations in cosmology
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Graduate Gravitational Instability and accelerated explanation of Universe?
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Undergrad Can Hawking Radiation Exist If Nothing Escapes a Black Hole?
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Graduate What is Faraday pulsation and how does it impact radiative transfer?
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Undergrad Photons being blueshifted when crossing evolving voids?
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Undergrad Falling into a massive black hole is not necessarily noticeable
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Graduate What Is the Scale Length in SPARC Data Analysis?
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Undergrad Big bang at the edges of the Universe?
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High School What is the Borde-Guth-Vilenkin theorem?
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Undergrad Does dark-energy require a source of energy?
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Undergrad Rotation curves and apparent mass of a galaxy
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Undergrad Could the Universe Be Much Older Than 13.8 Billion Years?
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Undergrad Is there any mechanism possible for the Big Brake?
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Undergrad How Does Inverse Bremsstralung Affect Photon Absorption?
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High School Nuclear Fusion in the Singularity
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High School How long is the start up time for a simulation of the solar system's formation?
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Stargazing Betelgeuse will be eclipsed by an asteroid
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Undergrad Einstein ring and Einstein Cross
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Undergrad How Do Moons Influence the James Webb Telescope's Position at Lagrange Point L2?
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Undergrad Did James Webb cast serious doubt on the Big Bang?
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Undergrad Dark energy and the kinematic Sunyaev-Zeldovich effect?
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Stargazing What is the maximum distance that parallax error can be used?
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Graduate What is the origin of the Dipole Repeller and similar structures?
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Graduate Planck evidence for a closed universe and a crisis for cosmology 2019
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High School Can We See This Massive Coronal Hole on the Sun?
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High School "If a black hole has more mass then the event horizon shrinks" ???
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Undergrad Avoiding structure collapse due to dark energy?
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Undergrad What is “absolute circular polarization fraction” for a pulsar?
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High School How Does a Massive Planet's Orbit Around the Sun Appear?
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High School Why Is Universal Attraction Used If Galaxies Accelerate Apart?
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High School Amaterasu and GRB221009A: A Comparison of Cosmic Rays and Gamma Ray Bursts
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High School More Experimental Evidence for MOND
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Undergrad Why didn't the Big Bang form a Black Hole?
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Undergrad Why Does NASA Claim 10-100x Better Bandwidth from Optical Communications?
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Undergrad What does the output of a radio telescope look like?
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Stargazing Has a Deep Field Picture of the Sky Been Captured with a Radio Telescope?
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Undergrad More extended equilibrium configurations due to dark energy?
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