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.
Graduate Change in average atomic mass in universe through time?
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Undergrad View of a Void: Intergalactic Space & Dark Energy
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Undergrad Flatness Problem: Critical and Actual Density
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Undergrad Gravitational field inside a void
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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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High School Albedo, atmosphere, and predicted temperature of Venus
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Graduate 1st and 2nd moments of H(mu) function
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Graduate Planar orbit of planets around sun
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High School Is fusion in an accretion disk of a black hole possible?
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High School Do Atoms in Neutron Stars Touch Each Other?
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High School Are colors in astro photos 'real'?
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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 Default 'now' when discussing astronomical things
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High School Question pertaining to dark energy
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Undergrad Where galaxies are now or is there a universal 'now'?
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Undergrad Some questions regarding the initial singularity
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High School Why Were Planets Visible to Ancient People but Not Us?
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High School Why does the Great Red Spot spin counter-clockwise?
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High School Could Dark Matter Be the Fifth Fundamental Force of Nature?
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Undergrad Inflationary Energy: Origins & Conversion
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High School Can the space to have new properties without researching?
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Graduate What Are the Next Greatest Effects on the Moon's Motion?
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Graduate What happens to the red dwarf during a classical nova?
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High School Before Big Bang: Can We See What's Beyond?
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Undergrad Infinity vs Expansion: Is an Infinite Universe Compatible with Expansion?
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Graduate Do cosmologists take spontaneous symmetry breaking seriously?
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Graduate Charge balance in observable universe
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Graduate Synthetic Black Hole Event Horizon Created in UK Laboratory
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Stargazing Will You Be Watching the Perseid Meteor Shower?
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Undergrad The declination at the horizon in the east at a latitude
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Graduate What are the most common programming languages in astro?
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Undergrad How is it possible for a ring singularity?
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High School Understanding the Perseid's Motion in Relation to the Sun
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Undergrad Is Redshift Always Proportional to Velocity?
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High School What Makes the Sun's Gravity Well So Deep Compared to Earth's?
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Undergrad Could Chemistry Occur in Titan's Hydrocarbon Lakes?
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Stargazing What telescope is best for a beginner on a budget?
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High School Does LIGO detect back ground noise
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High School Is the Milky Way unique or do other galaxies have these voids in their centers?
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Undergrad Perhaps an unknown property of gravity....
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High School Before the big bang video series
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High School How Did Light Originate After the Quark Epoch?
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High School Is there a such thing as being outside of our sun's gravitat
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Undergrad What Triggered the Big Bang Singularity's Expansion?
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Undergrad Hubble parameter in terms of the scale factor
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Undergrad Is the boundary of a star objective or subjective?
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High School Could a New Field Explain Dark Matter's Role in the Universe?
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Undergrad Astronomers make first accurate measurement of oxygen in distant galaxy
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High School Some more basic questions on Dark Energy
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High School Is the Andromeda Galaxy Green Shifted and How is Red Shift Measured in Practice?
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Undergrad How is motion in space different than motion in spacetime?
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High School How does the Universe's expansion relate to Newton's 1st law
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Stargazing Telescope Design: Calculating Total Distance from Primary Mirror to Eyepiece
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High School Explanation of the asymmetry of the Universe
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Graduate Venus to be humanity's next destination?
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High School Gravitational Orbit: How Size Determines Distance & Speed
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Undergrad What Does Absolute Magnitude in the B Filter of a Distant Galaxy Refer To?
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High School The Milky Way's Dark Twin Revealed
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Undergrad Why is the density infinite at the singularity?
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High School What caused the uneven distribution of mass/energy?
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Stargazing What should I observe in Southern Skies during my trip to South Africa?
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High School What Would the Moon's Apparent Magnitude Be 1000 Times Closer?
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Undergrad Is Superdeterminism the Key to Understanding Our Universe?
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Undergrad Focus of Earth's elliptical orbit
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Undergrad Does Mass Bend Time?
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Graduate Can Dark Energy be eventually infinite?
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High School Vectors & Gradients: Confused? Get Answers Now!
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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 How do I convert the number of efolds to conformal time during inflation?
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Graduate Need help with satellite navigation? Any textbook recommendations?
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Undergrad How can the integral be rewritten using a change of variables?
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High School Hubble flow and velocity addition
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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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Graduate Whats the genesis of quantum foam,planck constant, & string
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Undergrad Difference between hubble sphere,particle horizon and event
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Undergrad What is the significance of the cosmological jerk in the expanding universe?
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Undergrad Is Infinity Inevitable in Our Understanding of the Universe's Beginning?
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Stargazing Radio Telescope Building Guide for Beginners
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Undergrad Where do high energy background photons go?
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Undergrad Explore the Immense Universe with the Incredible 3D Map | CS Monitor
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Undergrad Can Unification of Forces Coexist with an Eternally Inflating Universe?
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High School Where Can I Find Math for Black Hole Firewalls?
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High School Is the Speed of Light Dependent on the Size of the Universe?
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Undergrad Who really found out the Universe's acceleration?
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Undergrad Relations resolves singularity -- new paper on arxiv
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Undergrad How Similar Are the Images from BOSS and CMB Planck Spacecraft?
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Undergrad Which light do we use to measure flux?
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Undergrad Is Dark Energy an Established Force in the Universe?
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Undergrad Scale factor/redshift formula wrong at the end?
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High School Could a research base on Mercury be the key to unlocking solar mysteries?
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High School Is the Universe Finite or Infinite?
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Undergrad Gravitational waves affected by gravity?
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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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Stargazing Which Telescope Should I Buy for City and Country Use?
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Undergrad Night skies in a contracting universe, would they look blue?
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