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.
Graduate State of matter before a black hole is formed.
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Graduate Pressure in stars from photons vs. electron/positron pairs
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Undergrad Degeneracy pressure and interactions
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High School What Are Some Math-Based Topics for an Astrophysics Project?
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Undergrad Angular size of Venus: Is my math correct?
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High School *Quick question: When is VENUS visable in the sky in this period ?
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Undergrad Coordinates of Planets: An Astronomer's Guide
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High School Tele Vue / Meade laser test: question
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Undergrad Using Sloan Digital Sky Survey to find Planets
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Undergrad How Do You Calculate the Minimum Velocity to Escape the Solar System?
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Undergrad Polar coordinates of solar system
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Why can't we invest in privately owned Space Companies?
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High School How can I view a star catalog in a txt file?
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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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Undergrad The current planet count stands at 490
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Graduate Question about the edge of the universe
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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 Doppler effect of light spectrum
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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 Must a black hole be a point singularity?
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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 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 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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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 Lagrange Points, Maximum mass and their effects
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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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High School The origin of water in the universe
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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 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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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 Blow up a black hole by filling it with electrons?
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Undergrad Asteroid Sterilization: Size and Impact on Earth
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Undergrad Relationship between Altitude and Latitude
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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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Graduate The expanding universe and the conservation of energy
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Undergrad See the Light of Creation: Viewing the Big Bang
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High School Why do stars appear to be white in color?
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Graduate Accelerated Expansion of Space question
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Undergrad How do distance and age relate in astronomical measurements?
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Stargazing Is it Possible to Build a Simple Radiotelescope in Your Backyard?
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Undergrad What form of energy is lost when a planet changes orbit?
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Undergrad Universe from Nothing: The Mystery of the Big Bang Explained
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Undergrad Prove Binary System Brighter by 3/4 Magnitude Than Single Star
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Graduate Converting HJD to BJD: Equation and Code Solutions | Natski
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Graduate How Does Hawking Radiation Affect Black Hole Energy Loss?
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Undergrad Distribution of stars in spiral galaxies
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High School What is the maximum mass a planet can reach?
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Richest Planetary System Discovered
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Graduate CBR photon density at equilibrium temperature
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Graduate Explore Black Holes & Time: Is Time Stopping Possible?
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Graduate Hundreds of Rogue Black Holes May Roam Milky Way
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High School My First Iridium Flare - Unexpected Bright Light in the Sky
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