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 "Moment of Inertia" in Virial Theorem
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Undergrad What Makes Black Holes Black and White Holes White?
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Undergrad Where is the dead star that created us?
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Undergrad Why do Great Oppositions of Mars Always Happen at the Same Time of Year?
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Undergrad How can inhabitants of moon guess of its revolution
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Undergrad Infinity vs Expansion: Is an Infinite Universe Compatible with Expansion?
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Undergrad The declination at the horizon in the east at a latitude
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Undergrad How is it possible for a ring singularity?
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Undergrad Is Redshift Always Proportional to Velocity?
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Undergrad Could Chemistry Occur in Titan's Hydrocarbon Lakes?
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Undergrad Is the boundary of a star objective or subjective?
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Undergrad Astronomers make first accurate measurement of oxygen in distant galaxy
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Undergrad Focus of Earth's elliptical orbit
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Undergrad Does Mass Bend Time?
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Undergrad Is Jupiter too big to orbit the Sun?
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Undergrad Quasar Brightness: A Case of Light-Days or Light-Years?
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Undergrad Rotation curves of galaxies as a function of isolation.
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Undergrad First atmospheric spectroscopy of Earth-sized exoplanets
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Undergrad Explore the Immense Universe with the Incredible 3D Map | CS Monitor
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Undergrad Who really found out the Universe's acceleration?
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Undergrad Which light do we use to measure flux?
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Undergrad Scale factor/redshift formula wrong at the end?
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Undergrad Energy Released in Stellar Nucleosynthesis
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Undergrad State of the Universe if we increase/decrease the binding energy of deuterium
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Undergrad Escape Velocity: Unraveling the Mysteries of Kinetic & Potential Energy
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Undergrad Why was the early universe opaque?
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Undergrad Why do nebulae tend to collapse into discs?
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Undergrad Solar physics: coronal holes & sunspot cycles
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Undergrad Stopping or re-routing comet 67p
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Undergrad How Can We Measure Redshift Using the Spectrum of a Star?
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Undergrad How can we measure a galaxy's velocity via a star?
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Undergrad Determine the temperature of a star via its spectrum
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Undergrad Why do we calculate the density of states using k-space?
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Undergrad Neutron Star Stability: Speed of Sound vs Light
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Undergrad Seeing the Martian moons with a pair of $60 binoculars
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Undergrad How ancient found that sun is too far from earth?
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Undergrad Sun and hydrostatic equilibrium
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Undergrad Disequilibrium of the solar system
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Undergrad Why does temperature always rise in stars?
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Undergrad The cold interior of the Sun seen in a sun spot
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Undergrad Are Black Holes Truly 3D Phenomena?
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Undergrad How to define the rotation of a planet in retograde orbit?
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Undergrad Does the Universe have a centre, yes or no?
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Undergrad How well are orbital inclination oscillations known?
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Undergrad Seeking "simple" orbital path planning for game development
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Undergrad Can someone please explain to me Leavitt's law?
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Undergrad Radius and Mass of an Unknown Planet
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Undergrad What Size Space Bombs Would Detonate in Midair Based on Their Composition?
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Undergrad Light and our atmosphere (some quantum physics)
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Undergrad Dark Matter: Can Gravitational Field Be Generated?
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Undergrad Why do we need "planetary equilibrium temperature"?
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Undergrad Youtube video about the sound of a pulsar
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Undergrad Does Black Hole Evaporation Violate the Second Law of Thermodynamics?
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Undergrad Astronomical improvements needed to discover a ex-solar moon
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Undergrad Spacecraft Launches: Perigee & Apogee - Why Terminate?
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Undergrad How Do You Convert Parsecs to Arcminutes in Astrophysics?
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Undergrad Understanding the Polar and Equatorial Temperature Differences on Planets
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Undergrad Could Brown Dwarf Sub-Dwarf Companions Host Habitable Moons?
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Undergrad What is the size of the observable universe relative to CMBR
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Undergrad Calculating semi-major axis and minimum mass of an exoplanet
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Undergrad What Does MUV Mean in Astronomy? Understanding GN-z11 and its Redshift
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Undergrad How does mars have a magnetic field, with a cooled core?
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Undergrad The "real" reason why some galaxies are flat
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Undergrad How Many Einstein Rings Have Been Discovered?
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Undergrad Light speed moving objects -- What would it look like?
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Undergrad Is the Oort Cloud Just Speculation or a Real Cosmic Structure?
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Undergrad Superconductors and spacetime question
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Undergrad Hubble finds universe may be expanding faster than expected
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Undergrad How does the solar wind affect Earth's atmosphere?
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Undergrad What happens when tidal power runs out?
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Undergrad GW150914 and GW150914-GBM revisited
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Undergrad Is tangential velocity in elliptical orbits stable?
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Undergrad Closure Phase - Interferometry - Recurrence Relation
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Undergrad Aurora on Uranus? Why Are They In Large Dots?
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Undergrad See How Andromeda Would Look if It Were Brighter
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Undergrad Position and Velocity in Heliocentric Ecliptic Coordinates
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Undergrad Understanding Etherington's reciprocity theorem
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Undergrad Mathematical Proof of Kepler's First Law of Orbits
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Undergrad How to calculate day length of a tidelocked double planet?
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Undergrad Pluto's interaction with solar wind
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Undergrad The universe doesn't have volume from outside?
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Undergrad New light shed on birth of the universe
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Undergrad How Will Nano Spacecraft Reach Alpha Centauri?
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Undergrad Space Debris: Questions from a Newbie
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Undergrad Discovery of how to measure wavelength absorption lines
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Undergrad How Small Can a Mass Be Squeezed?
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Undergrad Gravity assist and increasing orbital energy
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Undergrad Could it be so easy? (Why is space three-dimensional?)
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Undergrad Where Can I Compare Star Spectra?
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Undergrad Evidence to support the theory of stellar nucleosynthesis?
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Undergrad Hawking radiation and energy-negative energy pair production
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Undergrad Comparing Earth's diameter with Moon's diameter
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Undergrad Star Radius & Mass from Spectral Class, B-V, Luminosity
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Undergrad How can I calculate red shift for intragalactic bodies
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Undergrad Could "reverse entropy stars" exist in our universe?
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Undergrad Does Space Compressibility Affect the Big Bang?
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Undergrad Meteor impact and axial tilt, relation to climate
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Undergrad What does cosmological redshift do to light
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Undergrad Calculating average density of the Universe
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Undergrad Factor of how much linear size scale has changed
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