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 Could Dark Energy Be Linked to a Primordial Mother-Universe?
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Undergrad Life on Mars: Evidence of Ancient Life?
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Undergrad Why Doesn't the Sun's Core Contain Heavy Metals Like Earth's Core?
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Graduate What made the universe have 3 dimensions, instead of some other number?
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Undergrad The current planet count stands at 490
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Graduate Variation of fine structure constant and spacetime?
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Graduate Question about the edge of the universe
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Graduate Size of the universe and human brain
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Graduate Accelerated Vacuum Space/ Universe Expansion
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High School Question why does the moon move around the earth
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Graduate Could the Big Bang Have Originated from a Black Hole?
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High School Understanding Buoyancy: Why Do We Float in Water?
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Undergrad Impacts of Excessive Gravity on Planetary Life
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High School Mysterious Flash in the Sky - Ask PF Community
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Graduate Eternal Inflation Time Will End
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Graduate Doppler effect of light spectrum
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High School How are clusters of galaxies formed?
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Graduate Is Panspermia a Viable Explanation for the Origins of Life?
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Undergrad Kepler's Third Law: Mass of Sun and Newton's Law
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Graduate Is the Cosmological Principle Limited to Space Only?
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Graduate Must a black hole be a point singularity?
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Graduate What is the relationship between spacetime and energy?
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High School Finding the Angular Distance Between Jupiter and its Moons (Galilean)
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Argument against Dark Matter - please enjoy yourself for a moment
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Graduate Could Solar Energy Beams Enable Interstellar Travel?
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Graduate Particles in our universe undetectable by us
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Graduate How is our speed (~605km/s) derived from the CMB dipole anisotropy?
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Stargazing Can Telescopes Show Recognizable Reflections at Long Distances?
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Undergrad Calculating Earth Masses in a Planet with Earth-Size and Moon-Density
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Undergrad Black hole gravitational question
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High School String of satellites transits moon?
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Graduate Is the Standard Model of Cosmology built on a house of cards?
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Graduate How much dark matter in each galaxy? Is it related to age?
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Undergrad Is space, time and energy linked?
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High School Moon Question (Vacuum, air, escape vel.)
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Graduate Can the Li7 problem be resolved by increasing the dark matter ratio?
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Undergrad Is Dark Matter Different from Dark Energy?
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Graduate Can the Magnetic Field of a Black Hole Reveal Its Charge and Rotation?
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Undergrad Constellation of date and the actual constellation that follows the sun
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Stargazing Trying to pick out a telescope (Need help)
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Stargazing Which Telescope is Best for Viewing Planets and Nebulae on a Budget in Wales?
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High School Comet Passing by Earth: Effects & Destruction
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Graduate Escape velocity when in earth's orbit
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Undergrad What Do You Call the Quantity When You Multiply Light Flux by Detector Area?
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Graduate Astronomy research question. Thanks
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Graduate How Does B Mode Polarization Help Trace Gravitational Radiation?
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Graduate About the origin of the universe? big bang cause?
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Graduate What Happens Inside a Black Hole's Event Horizon?
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Graduate Was the Universe Always Infinite from the Moment of the Big Bang?
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Graduate Lagrange Points, Maximum mass and their effects
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Graduate Are Matter and Space-Time the Only Things That Exist in Our Universe?
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Graduate What/how created first brane? first source of everything what/how
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Graduate Black Holes containg a Universe.
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High School Are there any geostationary orbits around the Moon?
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Graduate What Are the Key Questions About Supernova Data and the Modified Milne Model?
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High School The origin of water in the universe
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Graduate How dark energy make universe to inflate?
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High School Hi,please anybody tell any reference book for astrophysics.
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Graduate What If Our Sun Were Blue? - Effects on Perception & Evolution
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Undergrad Ow high above the horizon the sun would be on the vernal equinox
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Undergrad Could Black Holes Be Tears in Space?
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Graduate Were There Any Proposed Non-Expanding Cosmological Models Without Lambda?
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Graduate Is the Planck Length real? How do we know?
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Undergrad Quick angular measurement question about moon. Thanks
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High School Question about how stars appear to move westward?
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Graduate Wormholes expeling particles at superluminal speeds
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Astronomical software for BCE Thuban era
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High School Can you see Venus shining near the noon hour?
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Graduate Astrophysics from a Boobie or a black climate control.
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Graduate Can Black Holes Really Evaporate and Lose Mass?
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Undergrad Why Do Galaxies Have a Spiral Shape? Understanding Gravity's Role
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Graduate How does information leak out of a black hole ?
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High School Calculating speeds of radio to a planet
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Undergrad How do you calculate an intuitive date and time from the BIG BANG to NOW? :-)
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Undergrad Calculating Synodic Period using Sidereal Period: Is there a Reliable Formula?
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Undergrad The black hole isn't actually a hole
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Graduate Could the Gravitational Lensing Effect Explain the Galactic Rotation Anomaly?
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Graduate What is the significance of particle-antiparticle radiation near black holes?
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Graduate Identifying the Inflaton (new paper Easson et al)
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High School Which Direction Does the Milky Way Span Across the Sky?
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Graduate Bifurcated Asteroid - Centrifugal force
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Undergrad Is the universe a closed system?
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Graduate Did Matter Exist Before Space-Time Began?
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High School What keeps the planets in their consistant orbit?
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Graduate Is accounting for relativistic effects necessary in solar system simulations?
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Undergrad What causes variations in redshift measurements?
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Undergrad The universe is expanding & the universe is infinite
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Graduate Looking Back Through Spacetime in the Future
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Graduate Blow up a black hole by filling it with electrons?
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Graduate Yet another Dark Energy question
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Graduate Used infinity to predict that another ClamShell
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Graduate On String Theory's Predictiveness
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Graduate Is the Big Bang Expanding into a Preexisting Void?
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Undergrad Asteroid Sterilization: Size and Impact on Earth
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Graduate Time at the edge of the universe
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Graduate Impact of Free Will: How Much Can We Alter Universe?
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Undergrad Relationship between Altitude and Latitude
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Graduate Dark Matter Distribution Around Galaxies
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Graduate Can High Temperatures Enable Silica Formation in Anaerobic Lunar Environments?
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Undergrad Have you ever taught orbital mechanics to middle schoolers?
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