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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 The Expanding Universe: Why Stretching is the Only Explanation
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Undergrad Dark Matter Simulation: Help Choose a Program Language
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High School Align Earth, Sun & Milky Way: Date Revealed
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Graduate Is the Universe Alive? The Fascinating Theory of an Evolving Cosmos
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Undergrad Is the Evolution of Matter Density Proportional to a^3 or 1/a^3?
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Undergrad Is Gravity Like a Bed Sheet and Baseball?
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Graduate Has the Three Body Problem Ever Been Solved?
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Undergrad Stars colliding/meeting up with each other
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Graduate Speed of light and universal expansion.
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Undergrad Universe expansion VS speed of light
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Transit of Mercury 2006: Tips for Capturing Photos | Physics Forums Blog
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Formation of the Moon: Did You Catch its Name?
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Is There Liquid Beneath Saturn's Monster Storm?
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High School Time taken to form universe, religion vs science.
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Undergrad What is Space Physics and How Does it Relate to Cosmology and Astrophysics?
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Graduate Where Does The Hawking Radiation Go?
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Creating a Time Machine: Can it be Done?
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Graduate Supermassive BHs: Forming Farthest Quasars
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Undergrad Earth changing tangental velocity?
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High School No storm on Earth lasts like the one on Jupiter
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What Defines Our Individual Universes?
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Undergrad How Would Changes in the Sun's Mass and Earth's Velocity Affect Earth's Orbit?
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Graduate Does the PA show that DM/DE is dynamically important in the outer solar system?
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Undergrad Understanding the Expanding Universe: A Simple Analogy for Kids
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Evaluate the pic : got a black spot in sun
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Graduate Could Matter Exist in a Black Hole on the Level of Quarks?
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Graduate What if the Universe had this cosmology
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Graduate Max Gravity Boost: Hyperbolic Trajectory from Jupiter
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High School A question related to solar system
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High School What Can You See in the Night Sky with the Current Comet?
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Can the Hubble Repair Mission Extend the Life of NASA's Beloved Telescope?
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Undergrad Would Earth's Rotation Change If the Moon Exploded?
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High School The sun's gravitational pull on the earth
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Undergrad Why are the emission lines in the Crab Nebula split into two?
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Astronomy Question: Differences Between Nebula and Death Star
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High School Varibles/Eclipsing Binary systems
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Graduate Newtonian derivation of Friedmann equation
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High School Does a Geo-Synchronous Satellite Catch a Shadow?
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Graduate Is the CERN particle accelerator risking a phase change in the Universe?
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Graduate On black holes and the implications according to me.
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Undergrad Are There Habitable Planets Orbiting Alpha Centauri?
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Undergrad When will Andromeda galaxy look as big as the moon today?
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Undergrad The Dominant Source of Earth's Surface Heat: Solar Radiation or Interior Heat?
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Undergrad Lunar Phase Change with Reversed Moon Orbit
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High School What Is Galactic Motion and How Is It Explained?
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Undergrad Why Hasn't the Kuiper Belt and Scattered Disc Coalesced into a Planet?
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High IQ & the Universe: Perceiving Patterns & Cycles
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Undergrad IAU Redefines the Solar System: 12 Planets, Countless Possibilities
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High School Conveyor Belt on Sun: What is it & How Does it Link to Solar Storms?
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Solar Storm Ideas: Share Your Thoughts Here
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Graduate Effect of dark matter on solar system dynamics
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Graduate Does Kepler's Third Law Account for Dark Matter in Galaxy Rotation Curves?
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Undergrad Solar wind + Weak magnetic field = No water?
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Graduate Turbulence pressure in convection zone
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Graduate My calculation of the density of the universe at (10^60)th of its present age
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Undergrad What Properties Can Be Extracted from the Hipparcos Catalogue?
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Undergrad ExoPlanet Hunting: Observing Stars with Celestron C11 XLT
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Graduate Discover the Universe's Undensity with the Human Body Calculation
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Stargazing How does the reappearance of Io during an eclipse relate to linear lighting?
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Saturn's Rings Backlit: Glorious Detail & Light
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Graduate Limitations on cosmology for observers restricted to Earth
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Graduate What Theories Explain Quasar Energy Concentration and Their Challenges?
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Graduate What does it mean for the universe to be globally flat,
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Graduate Universal expansion reaching a point of equiblirium
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Graduate What Are the Effects of Extreme Pressure on Electron Degenerate Matter?
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Graduate Big Bang and Simultaneity question
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Undergrad Redshift - does energy fade or get absorbed?
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Graduate Would an Object Fall Straight Through a Hole in a Spinning Planet?
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Graduate What are the leading theories behind the formation of dwarf galaxies?
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Undergrad Light years-distance or light travel time?
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Undergrad Proving Venus's Orbit is 0.72x Earth's: Understanding Greatest Elongation
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Undergrad Can Gravity Create a Perpetual Motion System in Planetary Orbits?
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Graduate Why is the Poincaré dodecahedron not observed in the universe?
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Graduate Scalar field pressure and energy density
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Undergrad Horizontal system of celestial coordinates
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Getting Ready to Stargaze: My Orion Atlas 11 Arrives Soon
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Graduate How is Cosmic Background Radiation Generated and What Does It Reveal?
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Undergrad Gravitational pull is related to rotational speed?
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Undergrad What Is the Significance of Zero Right Ascension in Astronomy?
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Graduate Do galaxies have a negative mass defect?
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Graduate This universe would expand right?
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Graduate Inflationary Theory out of thin air?
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Cosmology & Physics Books: Recommended Reads
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Graduate Expanding Universe (an interestin mind experiment)
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Undergrad Measuring the absolute value of the AU
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Graduate Does the Maximum Entropy of a Black Hole Allow for Hawking Radiation?
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Graduate The possiblity of a solid planetary disk
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Graduate How to Solve Tolman-Oppenheimer-Volkov Equations for Neutron Stars?
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Graduate Mass of Black Holes: Measuring the Unmeasurable?
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Graduate Shape of the Universe: Evidence for Expansion in a Single Direction
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High School Finding Cruithne's Orbit & Return to Earth's Orbit
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High School Earth's Celestial Poles: North and South
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Graduate The Supernova Legacy Survey (SNLS)
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Graduate No HUP, a universe without unknowns?
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Graduate A question on the rate of time in the Light we observe
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Graduate New Nature Paper: Old Ia Supernovae different?
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Will NASA's Hubble Servicing Mission Save the Telescope?
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Evaluate the pic : got a black spot in sun
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Graduate Why Can't I Solve This Kepler's Law Problem Correctly?
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Graduate Are Extreme Internal Accelerations Significant in the Inflationary Universe?
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