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.
Why Do Disk Galaxies Appear to Spin Despite Irregular Redshift Patterns?
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What Are the Competing Theories in Astrophysics: Dark Matter vs MOND?
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Stargazing Increasing the resolving power of a telescope
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Could Gliese 581 Be Our Next Habitable Planet?
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How is measuring Redshift possible?
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Ideas for High School Astrophysics Course Syllabus
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New to astrophysics, don't have a good physics foundation, need some help
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What are the limits of interstellar travel?
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*Quick moon question - (about orbit)
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Formation of Stars: How Gas Spins to Fuel Birth
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Is this angular size calculation correct?
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Universe Origin: How Could Galaxy be 13B Light Years Away?
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How Does Gravity Work and What Causes Time to Slow Down Near a Black Hole?
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Stargazing Pictures I took at a 2.5m telescope in the Canary Islands
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Calculating the Earth-Sun distance during perihelion
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The Collision of Elliptical Galaxies: A Surprising and Promising Event
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Stargazing What is the Best Catadioptric Telescope for Portability and Versatility?
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Greenwich Mean Timt, GMT and Universal Coodinated Time, UT
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Question about having a Theory in astronomy. ?
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Question about Objects in Ultra Deep Field
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Stargazing Heyy, i've had a telescope before and know how to use them.Has
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Is Earth’s orbit far from circular?
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Stargazing What Are the Best Telescope Models Within the £100-£250 Range?
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Faster than Light Travel Side Effects
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Black holes giving birth to stars?
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How Do Stars Achieve Their Massive Sizes?
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What are the Current Main Research Topics in Astrophysics?
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Question about Phases of the Moon. Thanks
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Is the Waning Crescent Visible Near the Horizon?
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What would happen if you fell into a black hole?
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Tides & Moon Distance: Seeking Answers
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Stargazing Aug 21st, 2017, a total solar eclipse will cross the US
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What Causes Hypervelocity Stars to Eject from Black Holes?
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Calculating Gravities for Math to the Moon
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Astrometry and Elliptical orbits
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Can We Reach the Moon with a Slow, Steady Launch?
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How Can We Determine the Size of a Black Hole?
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Could Heat Exchange Be the Reason Behind Earth's Spin?
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Strange wikipedia entry about the sun's core
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The infinite possobilities presented by the infinite amount of probabilities
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Why are solar eclipses so short compared to lunar eclipses?
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Negative pressure and dark energy
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Why smaller particles come together
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Colliding Black Holes: Will the Smaller Get Pulled In?
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Define/explain this gravity calculation (picture)
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John Huchra Dies at 61; Maps Altered Ideas on Universe
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Can a QM/GR overlap provide a breakthrough in understanding gravity?
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What is the energy of the galactic magnetic field? (E/c^2)
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Plotting Intensity in Airy Pattern of Telescope - 1D
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Subatomic particle and space curvature
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Super black holes and stars orbiting them
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Super-black holes and the universe
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State of matter before a black hole is formed.
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Pressure in stars from photons vs. electron/positron pairs
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Degeneracy pressure and interactions
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What Are Some Math-Based Topics for an Astrophysics Project?
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Angular size of Venus: Is my math correct?
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*Quick question: When is VENUS visable in the sky in this period ?
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Coordinates of Planets: An Astronomer's Guide
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Tele Vue / Meade laser test: question
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Using Sloan Digital Sky Survey to find Planets
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How Do You Calculate the Minimum Velocity to Escape the Solar System?
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Polar coordinates of solar system
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Why can't we invest in privately owned Space Companies?
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How can I view a star catalog in a txt file?
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Life on Mars: Evidence of Ancient Life?
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Why Doesn't the Sun's Core Contain Heavy Metals Like Earth's Core?
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The current planet count stands at 490
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Question about the edge of the universe
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Accelerated Vacuum Space/ Universe Expansion
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Question why does the moon move around the earth
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Could the Big Bang Have Originated from a Black Hole?
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Understanding Buoyancy: Why Do We Float in Water?
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Impacts of Excessive Gravity on Planetary Life
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Mysterious Flash in the Sky - Ask PF Community
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Doppler effect of light spectrum
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Is Panspermia a Viable Explanation for the Origins of Life?
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Kepler's Third Law: Mass of Sun and Newton's Law
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Must a black hole be a point singularity?
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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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Could Solar Energy Beams Enable Interstellar Travel?
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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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Calculating Earth Masses in a Planet with Earth-Size and Moon-Density
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Black hole gravitational question
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String of satellites transits moon?
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How much dark matter in each galaxy? Is it related to age?
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Is space, time and energy linked?
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Moon Question (Vacuum, air, escape vel.)
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Is Dark Matter Different from Dark Energy?
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Can the Magnetic Field of a Black Hole Reveal Its Charge and Rotation?
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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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Comet Passing by Earth: Effects & Destruction
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Escape velocity when in earth's orbit
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What Do You Call the Quantity When You Multiply Light Flux by Detector Area?
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Astronomy research question. Thanks
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Lagrange Points, Maximum mass and their effects
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