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.
I Converting "Luminosity per unit wavelength" to "Luminosity per unit frequency"
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I Question Regarding Determining the Mass of Venus
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I What powers the quasar magnetic beams that power jets?
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I Material source of the quasar redshift
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I What are the names of these 2 craters on Mars....
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I What kind of matter formed Primordial Blackholes?
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B What is the definition of a black hole?
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I What is the correct way to calculate the area of the sky in square degrees?
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I 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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Stargazing Sun observation (Gregor / Teneriffa)
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I 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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B Are there any blue shifted galaxies name rc2?
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Stargazing Spotting Comet NEOWISE with Naked Eyes: A Spectacular Visual Experience!
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I Does a particular star's brightness change throughout the year?
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B Unraveling the Mysteries of Dark Gravity
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I Speculative Term in Drake's Equation
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I Effects of hydrogen anions in the solar atmosphere
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Glass bottle with a prolonged neck that continues into the inner space
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B By what process do different sized stars form?
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B Mars Terraforming: NASA & Beyond - Plans & Prospects
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B 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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I Does gravity affect aging on different planets?
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I Magnitude limits for active galactic nuclei
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I Does the expansion of the Universe affect orbiting bodies?
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B UV timelapse of the Sun in 4K, 52 min = 1 second
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B Why is the momentum of a star equal to the momentum of a planet?
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B Question re binary star systems & possible orbits
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I Are stable orbits possible between Mars and Jupiter?
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Stargazing The Curse of Elon Musk: Redirect Satellites to Sun or His Backyard?
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I Can you See Neighboring Asteroids from an asteroid?
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A Oddly specific question for help regarding a satellite in a shadow
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I Are Intensity and Magnitude independent of the radius of a star?
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What effect will SpaceX's 42K satellites have on astrononical viewing?
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I Reionization and the free-flow of light
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B The Coronal Heating Problem - The Hydrogen Fusion Core disappears?
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Stargazing Planetary orbits -- Why do planets orbit at same “level”?
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B Mining asteroids for minerals and resources?
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I What causes Kuiper/Ort cloud objects to become comets?
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B Rationale behind certain aspects of Space exploration
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Stargazing Assessment of astronomical numbers like those of Proxima Centauri
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B Star Photography: Can We See Stars as Disks?
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B Expansion of the Universe and the fourth dimension
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B Would lightning be possible on brown dwarfs?
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I How does the perihelion passage affect the orbital period of comet Neowise?
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I Is Triton ever hidden behind Neptune?
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B What Are the Linear Dark Features on the Sun?
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Solar System Dynamics page at NASA/JPL
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B Are the telescopes at Mauna Kea available for anyone to use?
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I How bright of a bolide would a Saturn IV-B stage be if it hit Earth
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B The Hubble Telescope Images a Magnificent Galaxy With “Flocculent” Spiral Arms
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I CCD Readout Noise vs Temperature
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B Why certain stars seem to move very little in the sky
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A Collision-dominated plasma (stellar coronae)
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I Observing colour through telescopes
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I Black Hole Observations: What Changed?
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B Could a Black Hole Power Civilization?
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How to prepare my camera for a solar eclipse
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Insights 3 Possible Models For Why Uranus Spins on Its Side
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I Do more impact craters always signify old age of a surface?
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I Formula: velocity of circular orbit wrt Schwartzschild metric
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I Possible webpage title: Is There an Upper Limit to the Size of a Black Hole?
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I X-ray Astronomy: Charged Ions Energy Distribution
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Stargazing Does anyone know where Earth's gravity stops and space begins?
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I Answers to a question about extraterrestrial life
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I Foreground & Background in Astrophysical Observation
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B Consequences of the Existence of Gravitational Waves?
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B An objective Bayesian analysis of life’s early start & late arrival
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I Persistent features of astronomical bodies
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I A cold, massive, rotating disk galaxy 1.5 billion years after the BB
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I Power output of red dwarfs turning yellow and blue?
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I What is column density in astronomy?
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I Question regarding the future of galaxies within a group of clusters
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Stargazing Backyard astronomers, how do you decide what to look at?
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B Behavior of compasses AFTER the magnetic pole
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B Discover the Black Hole Growth Rate: Time Frame for Consuming Planetary Mass
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I Trying to grok the draconic year
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Stargazing Wasp-76b is a planet where it rains iron
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I Could life on Earth survive the far future?
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I What stars were observed @ 1919 solar eclipse to prove relativity?
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I Black hole image: What are those "lobes"? [M87 10April2019]
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I The effect of Faraday braking on the Earth’s orbit
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A Is this evidence that Venus originally had a nitrogen atmosphere?
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I IAU Rotational Models: Sol Solar System Planet Info
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I Why the center of black holes should be different from neutron stars?
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B USGS Moon Map w/ Legend: Help Finding & Enlarging
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I White dwarf Ultra-relativistic electrons
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I Is it possible for the Moon & a pair of planets to conjunct as smiley face?
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A Can a single star with 6 to 8 solar masses end up as a supernova 1a?
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I The Bullet Cluster: 1E0657-56 vs. 1E0657-558
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B Free Online Lecture: Seeing the Unseeable - Capturing an Image of a Black Hole
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B What Did Hubble See On Your Birthday?
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Stargazing Wicked pink supermoon the other night Pics
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Stargazing Personal opinions please Lunar/martian meteorites or not?
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B What is the Cooling Time of a Neutron Star?
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I How does Jupiter protect the Earth from collision with space rocks?
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B Neutron Star Paradox: Understanding Coulomb & Gravitational Forces
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