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.
Undergrad Calculating what latitude aurora is visible using KP Index
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Graduate Blackhole radiation v Second Law
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Graduate Mass of the Universe: What's the Real Number?
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Graduate Ratio of positive to negative hydrogen ions in the universe?
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Undergrad Would the outer planets in our solar system survive a supernova event?
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Undergrad Problems understanding how universe has no center.
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Undergrad How do you find the temperature of the boomerang nebula?
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Graduate Infinite universe and energy/matter boundaries
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Undergrad Can Light Alter the Velocity of Asteroids in Space?
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What Makes the Metric System Essential for NASA's Mars Mission?
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Undergrad What are past values of the Hubble constant and is there an archive for them?
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Graduate Dark Energy as Gravitational Tidal forces?
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Undergrad Relationship between Gravity and Density
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Undergrad Find Historical Critical Density Data
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Graduate A quick question from a layman about folding space time
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Graduate Recent measurements suggest the universe it is flat and infinite
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Do Stars Have Van Allen Radiation?
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Graduate Understanding the accelerating universe.
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Graduate How can we claim the Universe is 13.7 billion years old?
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Graduate Where Will Our Universe End? An Unanswerable Mystery
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Graduate Big bang , physical constants , possibilities
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Graduate Is the Universe an Expanding Wavefront?
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Undergrad Why do some nebulae form into stars while others remain diffuse?
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Graduate Alan Guth, Gravitationally repulsive material?
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Graduate What is the radiation pressure on Earth if the sun was replaced by a black hole?
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Undergrad How to Determine Absolute Magnitude
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Graduate How could nothing is finite yet unbounded?
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Graduate Are Primordial Black Holes the Missing Piece in the Dark Matter Puzzle?
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Stargazing Single-dish radio telescope aperture
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Graduate Universe Expanding - Effects On Gravity?
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Graduate Resurrection of the WIMP as DM candidate
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Graduate How can light be older than the universe itself?
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Graduate Is Time's Arrow Anomaly Explained by Planck's Constant? | Physics Concept"
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Graduate Latest research in multidimensional space.
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Graduate How are elements produced in stars after iron?
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Graduate What speed is required for a 30-year journey to Alpha Centauri?
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Graduate Is Dark Matter Actually Energy with Gravitational Effects?
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Graduate White Holes created our Universe
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Graduate Exponential potential for inflation
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Graduate Why Does Iron Take More Energy to Create Fusion Than Other Elements?
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Graduate What is the nature of information in black holes?
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Undergrad Could gravitational lensing prove the universe to be older?
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Undergrad Saturn-Sized Star Will Live For 12 Trillion Years
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High School Hubble Picture Crushes Your Sense of Scale
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Graduate Matter vs Antimatter: Why Does Universe Have More of the Former?
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Graduate What will be the trajectory of space objects?
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Graduate Comparable size of the observable universe immediately after inflation
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Graduate Regarding graviton and negative energy
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Graduate Early cosmic inflation and the expansion of the universe.
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Undergrad How can we improve asteroid detection to prevent future impacts?
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Graduate Elliptical Orbits and Resonance of Eccentricities
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Graduate What Are the Key Findings of the Pulsar Radio Astronomy Experiment?
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Graduate PSR J0348+0432, Pulsar with white dwarf companion
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Graduate How does one measure the angle of Sun and Mars at different time?
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Graduate Standing in nothingness before the Big Bang
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Undergrad Coronal Mass Ejections - Would we be able to
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Graduate Derivation of the quadrupole moment of gravitational wave
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Graduate Is Self-Adjusting Isotropy a Valid Concept in Gravitational Theory?
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Graduate Restframe U-V vs V-J colour-colour plot
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Graduate Are Most Galaxies on Collision Courses Despite Dark Energy's Influence?
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Undergrad If energy cannot be created or destroyed, what is the universe?
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Graduate Hulse-Taylor pulsar and GR what if orbital velocities were higher?
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Stargazing What Can I See with My Celestron FirstScope?
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Graduate Could the Big Rip Lead to Another Big Bang?
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Graduate Universe is fine tuned for life
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High School Gravitational Force: What Causes It?
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Graduate Could Stereoscopic Imaging with Heliocentric Satellites Revolutionize Astronomy?
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Graduate Neutron Stars vs Atoms: A Comparison
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Undergrad How did Kepler know that the time of Mars' orbit was 687 days ?
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Undergrad Theories on the beginning of the universe before the Big Bang Theory
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Graduate Guth, Kaiser and Nomura versus Ijjas,Steinhardt and Loeb
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Graduate Entanglement of Higgs boson to explain dark energy
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High School Do less bright stars have redder spectrum?
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Graduate How Do We Know the Universe Started from a Single Point?
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Graduate Question about extreemly large black holes.
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Undergrad Forming of our Galaxies or Atmosphere
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Graduate Any books that explain the origin of physics stuff after the Big Bang?
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Graduate Gravitational Attraction, Electromagnetic Radiation and Dark Matter
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Undergrad What happens to meteors after they vaporize?
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Graduate Magnetic confinment of plasma/sustained fusion
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Graduate Would a single black hole form in the big crunch scenario?
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Undergrad All stars in Milky Way equal one square light year?
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High School What Pope wanted Galileo to include in his book
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High School How Does Sunlight Reach the Moon During a Full Moon?
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Undergrad Is Empty Space Truly Void of Energy and Matter?
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Graduate In the beginning there was one force
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Graduate What is the significance of the Eridanus Supervoid in the universe?
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Undergrad Doppler effect vs expansion effect on wavelength
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High School Questions About Things in Orbit and Why They Don't Descend
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Graduate Synchronization of time impossible?
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Undergrad Kepler's 2nd.law and calculation
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Graduate Could an eliptical galaxy exist with an axis of rotation?
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Graduate First detection of pop III stars?
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Graduate Comparing FLRW and Scale Factor Metrics
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Graduate Titan's atmosphere vs temperature.
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Undergrad Calculating HZ for Contact Binary Systems
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Graduate Is Our Universe Truly a Hologram?
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Undergrad How Large Can a Planet be and Still Have Earth's Mass?
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Graduate Does Time Cease to Exist Without Matter?
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Undergrad Satellites in various orbits above the earth exploded?
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