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.
High School Why is an inverse logarithmic scale chosen for the magnitudes of stars?
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Stargazing Observations and telescope/microscope design questions
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Undergrad Can LIGO Detect Gravity Waves from Directly Above or Below?
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Undergrad Red shift / Blue Shift - Gravity Well Roundtrip
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Undergrad What is the density of hydrogen atoms in the Universe?
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High School What is the relative speed of two groups of quasars with different redshifts?
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Undergrad Apparent distance to far galaxies
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High School There's Gold in Them Neutron Stars - or - Maybe Not
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Undergrad Object in or out of a circular field of view? (celestial coordinate system)
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High School If a coronal ejection like this happened during a total eclipse ....
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Undergrad Is a Robust Estimate of Tau Ceti 'f' Albedo Possible?
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Undergrad Rotation rates of planets seem odd?
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High School Measuring distance between two stars in a binary system
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High School Is there a forum where people can share and discuss features on Mars?
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Graduate Experimental test of shrinking matter theory?
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Undergrad Multiple Universes Coming into Contact
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Undergrad Converting "Luminosity per unit wavelength" to "Luminosity per unit frequency"
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Undergrad Question Regarding Determining the Mass of Venus
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Undergrad What powers the quasar magnetic beams that power jets?
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Undergrad Material source of the quasar redshift
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Undergrad What are the names of these 2 craters on Mars....
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High School Is the Big Bang only about the observable Universe?
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Undergrad What kind of matter formed Primordial Blackholes?
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Undergrad New Hubble Paper On Lensing In Galactic Clusters
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High School Questions about the Curvaton particle
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High School What is the definition of a black hole?
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Undergrad What is the correct way to calculate the area of the sky in square degrees?
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High School Finding the present day distance to a galaxy
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Undergrad What happens if a strangelet falls in to a black hole?
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Stargazing Apparent vs actual position of stars
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Graduate Accelerated Hubble expansion -- Is the second derivative positive?
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High School Can Time Truly Flow Backwards in Quantum Physics and Cosmology?
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Stargazing Sun observation (Gregor / Teneriffa)
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Undergrad Effect of Dark Matter on fast moving bodies
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High School Tidal Locking question about the Earth-Moon system
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High School Question about the size of atoms as time progressed
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Undergrad Remains of collapsed stars as touching binary planets?
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Stargazing Possibility of detection of Earth approaching objects by gravity?
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High School Are there any blue shifted galaxies name rc2?
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High School Why does our Universe have more electrons than positrons?
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High School Dark matter does not interact with ordinary matter....
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Stargazing Spotting Comet NEOWISE with Naked Eyes: A Spectacular Visual Experience!
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Graduate Binnig's fractal evolution applied to multiple universes?
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Undergrad Laws Before Big Bang or After Big Bang
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High School The accelerated expansion of the universe; redshift and time/distance
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Undergrad Does a particular star's brightness change throughout the year?
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Undergrad What Key Issues Should Cosmologists Address in the ΛCDM Model?
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High School Unraveling the Mysteries of Dark Gravity
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Undergrad Speculative Term in Drake's Equation
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Undergrad Effects of hydrogen anions in the solar atmosphere
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Undergrad Why can you not describe massive neutrinos with a temperature?
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Undergrad Glass bottle with a prolonged neck that continues into the inner space
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High School By what process do different sized stars form?
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High School Mars Terraforming: NASA & Beyond - Plans & Prospects
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High School Largest Moon With A Concave Orbit
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Old Astronomy Book Predicts the Kuiper Belt
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Stargazing Using DSLR movies for Astro Image stacking application
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Undergrad Does gravity affect aging on different planets?
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Undergrad Magnitude limits for active galactic nuclei
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Undergrad Does the expansion of the Universe affect orbiting bodies?
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High School UV timelapse of the Sun in 4K, 52 min = 1 second
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High School Why is the momentum of a star equal to the momentum of a planet?
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Undergrad Understanding the Discrepancy: Why Does the Moon Have Less Gravity Than Earth?
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Undergrad How do we observe the CMB at all?
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High School A Meritable Veritable Time Paradox?
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Undergrad What proof do we have that the universe is homogenous?
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High School Question re binary star systems & possible orbits
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Undergrad Are stable orbits possible between Mars and Jupiter?
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High School Low entropy early Universe and the heat death musings
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Graduate Can Cosmic Strings Trigger Vacuum Decay?
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Stargazing The Curse of Elon Musk: Redirect Satellites to Sun or His Backyard?
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Undergrad Can you See Neighboring Asteroids from an asteroid?
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Graduate Oddly specific question for help regarding a satellite in a shadow
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Undergrad Are Intensity and Magnitude independent of the radius of a star?
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High School What effect will SpaceX's 42K satellites have on astrononical viewing?
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Undergrad Reionization and the free-flow of light
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High School The Coronal Heating Problem - The Hydrogen Fusion Core disappears?
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Undergrad How Does The Cosmic Microwave Background Show That The Universe is Expanding?
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Stargazing Planetary orbits -- Why do planets orbit at same “level”?
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High School Mining asteroids for minerals and resources?
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Undergrad What causes Kuiper/Ort cloud objects to become comets?
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High School Rationale behind certain aspects of Space exploration
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Undergrad Is Negative Dark Energy Density a Valid Concept in Universe Models?
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Stargazing Assessment of astronomical numbers like those of Proxima Centauri
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Graduate Exploring Minkowski: A Multi-Dimensional Grid for Studying Other Spaces?
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Undergrad Meaning of the inertial energy density
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High School Star Photography: Can We See Stars as Disks?
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Graduate The Cosmological Principle means infinite Observable Universes
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High School Expansion of the Universe and the fourth dimension
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High School Would lightning be possible on brown dwarfs?
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Undergrad How does the perihelion passage affect the orbital period of comet Neowise?
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Undergrad Is Triton ever hidden behind Neptune?
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High School What Are the Linear Dark Features on the Sun?
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Solar System Dynamics page at NASA/JPL
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High School Are the telescopes at Mauna Kea available for anyone to use?
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Undergrad CMB creation, distance measurement question
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Undergrad How bright of a bolide would a Saturn IV-B stage be if it hit Earth
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High School The Hubble Telescope Images a Magnificent Galaxy With “Flocculent” Spiral Arms
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High School How was the amount of matter in the Universe determined?
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High School Did energy begin to exist? Can energy exist without space and time?
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