Astronomy and Astrophysics Forum

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Join in expert discussion on the topics of Astronomy and astrophysics. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
B Why isn't there an effort to name non-stellar celestial objects?
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B Rock Found in Field Turns Out to Be 4.6GY Old Meteorite
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A How do I determine the surface magnitude of a galaxy from a SED?
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I What are the Dynamics and Impacts of a Type II Supernova?
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I Why Does Spectral Line Darkening Occur Despite Photon Re-Emission?
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B How Is Solar Wind Temperature Measured?
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B What is the difference between a rocky planet's core and the Sun's core
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I Adding more meteorites to my collection
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B Can Spacetime be Torn According to Quantum Theory of Gravity?
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B How did ancient astronomers track changes in positions of stars?
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B Did I Capture Sunspots in My Summer Sunset Timelapse?
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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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I 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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B What Does the Astro Physics Equation from Lewis Season 8 Episode 2 Mean?
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I Why Does Gravity Remain when Star Mass Dissipates?
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Stargazing Is There an Unidentified Object Near the Horsehead Nebula?
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B What Medium Does Light Travel Through in Space?
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B Is the barycentre of the Pluto - Charon system also the L1 point?
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B Debunking Bat and Skull Nebulae fakery
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A Why Is the Hamiltonian Approach Preferred for the Restricted Three Body Problem?
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I Plotting the orbits of the planets from Ephemeris data
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B Celestial plane orientation to the galactic core
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I Help identifying this Tumbling object in a night sky photo from Namibia
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I Why Do Stars in Binary Systems Assume a Teardrop Shape?
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I Can Hawking Radiation Exist If Nothing Escapes a Black Hole?
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A What is Faraday pulsation and how does it impact radiative transfer?
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I Could the Universe Be Much Older Than 13.8 Billion Years?
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I How Does Inverse Bremsstralung Affect Photon Absorption?
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B Nuclear Fusion in the Singularity
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B 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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I Einstein ring and Einstein Cross
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I How Do Moons Influence the James Webb Telescope's Position at Lagrange Point L2?
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Stargazing What is the maximum distance that parallax error can be used?
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B Can We See This Massive Coronal Hole on the Sun?
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B "If a black hole has more mass then the event horizon shrinks" ???
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I What is “absolute circular polarization fraction” for a pulsar?
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B How Does a Massive Planet's Orbit Around the Sun Appear?
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B Amaterasu and GRB221009A: A Comparison of Cosmic Rays and Gamma Ray Bursts
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B More Experimental Evidence for MOND
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I Why Does NASA Claim 10-100x Better Bandwidth from Optical Communications?
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I 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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B How to calculate Aphelion distance?
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B What keeps most galactic stars from falling into the centeral black hole?
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B How Do We Calculate the Number of Atoms in the Universe?
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I Is Dark Matter the Key to Understanding the Pre-Visible Universe?
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I Can You Build Your Own Radio Telescope at Home?
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B Visible Light Through a Wormhole
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B First light from the Euclid telescope
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I Telling time on Iapetus and other general questions about Iapetus
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I An asteroid the size of the Rose Bowl has a slight chance of impacting Earth?
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I Solar Calendar -- When was the leap day inserted?
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I How Can We Measure Properties of Distant Planets and Stars?
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I Nuclear reactions in the Sun and other topics on stars
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I Formation of emission lines and other topics
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I Star cluster in the Milky Way appears to be as old as the Universe
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B Does the Universe prefer certain kinds of matter based on the laws in place?
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I How does gravitational self-interaction affect the Milky Way Galaxy?
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B Supernova Ejection: How Large Are the Chunks?
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I Is it possible to build a Telescope the Size of Half the Solar System size using all Lagrange Points?
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Stargazing Understanding the Formula for Sunrise and Sunset Calculation
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Stargazing How can we be sure that Leavitt’s law works?
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B Annular eclipse October 14, 2023
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B Can anyone suggest a good website to buy astronomy equipment?
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B Which star is the closest red giant to Earth according to The Guardian?
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B Is the existence of Planet 9 supported by Modified Newtonian Dynamics?
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I “Interpreting astronomical spectra” -- Continuum origins
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I Location of the magnetopause using Chapman-Ferraro equation
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NASA's DART spaceship has hit the Dimorphos asteroid: what now?
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B Why Does an Einstein Ring Have Four Images?
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B Difference between autumnal and vernal equinoxes
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I Resolution of observation telescopes?
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I Can astronomical observation take place in daylight in Antacrtica?
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I Is El Gordo's Collision Velocity Challenging ΛCDM?
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B SubNeptune planet K2-18b shows methane and dimethyl sulfide
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B Questions about relative Space-Time in the Universe
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I Surely the 2nd Law of Thermodynamics is defied by gravity?
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I Formation of rocky planets without a star
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B Do changes in speed always affect orbit size, and vice versa?
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I Formation of jets with accretion disks at black holes
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I Inquiry Regarding the Determination of the Galactic Disk's Outer Bound
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I Why Didn't Henrietta Leavitt Sign Her Own Discovery Paper?
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B A Question about Cosmic Background Noise
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I Comparing the formation of the atmospheres on Earth vs Venus
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B More Evidence for MOND -- Globular cluster galactic acceleration imprint
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I Obtaining Transit Spectrum for Celestial Bodies Using JWST NIRSPEC
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A How to convert mW/m^2 to W/m^2/nm?
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I What is the accuracy of parking spacecraft into Lagrange points?
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A Advice needed for exposure time computation for galaxies
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I Anyone know about the bolide across the Gulf Coast Fri July 14, 2023?
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I Error in Euler angles and quaternions
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I Without degeneracy, when would Solar cores collapse?
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Stargazing Question about my photos of a Full Moon -- What is this point of light?
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B Can BepiColombo Detect Microbial Life on Mercury?
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I Lines of stars that we see in the sky
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I Mass measurement of galaxies with non-gravitational means
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B Beware of "truthiness" in astronomy in seemingly reliable websites
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