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.
Undergrad Sun shade on Earth ground, is it a straight line or a curved line?
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Undergrad Orientation of the Earth, Sun and Solar System in the Milky Way
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Undergrad The linear polarization and brightness of pulsars
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High School Recommendations for International Research Competitions
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Undergrad Where Are the Missing Black Holes in the Milky Way?
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High School How to use the Binary Mass Function for exoplanets?
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Undergrad How fast were distant galaxies moving?
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Undergrad Speed of the umbra during eclipse vs rate of the Earth's rotation
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High School What is the actual shape of black holes?
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Undergrad Increase frequency of solar eclipses
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High School Things to try while watching the solar eclipse
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Undergrad Can there be slowly-falling accretion disks in black holes?
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High School How black hole Sgr-A* Was Found
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Undergrad Solar anomaly and the Antikythera Mechanism
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High School TV Series: 3 Body Problem - affects gravitational force?
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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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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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Graduate How do I determine the surface magnitude of a galaxy from a SED?
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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 Spacetime be Torn According to Quantum Theory of Gravity?
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High School How did ancient astronomers track changes in positions of stars?
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High School 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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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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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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Stargazing Is There an Unidentified Object Near the Horsehead Nebula?
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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 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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Undergrad Why Do Stars in Binary Systems Assume a Teardrop Shape?
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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 Could the Universe Be Much Older Than 13.8 Billion Years?
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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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Stargazing What is the maximum distance that parallax error can be used?
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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 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 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 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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High School How to calculate Aphelion distance?
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High School What keeps most galactic stars from falling into the centeral black hole?
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High School How Do We Calculate the Number of Atoms in the Universe?
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Undergrad Is Dark Matter the Key to Understanding the Pre-Visible Universe?
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Undergrad Can You Build Your Own Radio Telescope at Home?
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High School Visible Light Through a Wormhole
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High School First light from the Euclid telescope
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Undergrad Telling time on Iapetus and other general questions about Iapetus
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Undergrad An asteroid the size of the Rose Bowl has a slight chance of impacting Earth?
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Undergrad Solar Calendar -- When was the leap day inserted?
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Undergrad How Can We Measure Properties of Distant Planets and Stars?
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Undergrad Nuclear reactions in the Sun and other topics on stars
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Undergrad Formation of emission lines and other topics
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Undergrad Star cluster in the Milky Way appears to be as old as the Universe
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High School Does the Universe prefer certain kinds of matter based on the laws in place?
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Undergrad How does gravitational self-interaction affect the Milky Way Galaxy?
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High School Can Jupiter gravitationally eject a pebble in orbit? A smaller mass?
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High School Supernova Ejection: How Large Are the Chunks?
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Undergrad 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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High School Annular eclipse October 14, 2023
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High School Can anyone suggest a good website to buy astronomy equipment?
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High School Which star is the closest red giant to Earth according to The Guardian?
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High School Is the existence of Planet 9 supported by Modified Newtonian Dynamics?
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Undergrad “Interpreting astronomical spectra” -- Continuum origins
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Undergrad Effects of gravity on planetary core structure
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High School Am I attracted to a hydrogen atom 1 billion light years away?
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Undergrad Location of the magnetopause using Chapman-Ferraro equation
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