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 Calculate Star Radii: Mass, Luminosity & Temp
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High School Uncovering the Mystery of Dark Matter: A Beginner's Guide
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High School Does the Name of Mars Reflect its Ancient Oceans?
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Graduate Hellfire's introduction to quantum cosmology
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Graduate Does Time Reversal Symmetry Apply to All Interactions?
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Xena officially named Eris (as of 13 Sept)
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Graduate Do Penrose and Carroll Agree on the Specialness of Conditions for Inflation?
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High School Which exoplanet was the first comfirmed discovery?
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Undergrad Can Distance Alone Prove Gravitational Binding?
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Graduate Earth-Sun Distance Over Time: Stability & Changes Explained
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Undergrad Publications on the evolution of stars?
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Stargazing About Parabolic Telescope Mirrors
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Graduate Homogeneous and Isotropic Stress-Energy Tensor in Cosmology
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Undergrad What are Some Important Effects or Phenomena in Astrophysics?
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Undergrad Most Distant Black Hole Discovered: 13 Billion Light-Years Away!
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Graduate Moon Perturbations: Learn Differential Gravitational Forces
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Graduate Is Matter and Energy the Same Thing? Debunking Claims About Physics
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Graduate Permeability of free space question
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Graduate Can Thermal Fluctuations in Loop Cosmology Solve the Horizon Problem?
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Graduate Is Retro Causality the Key to Understanding the Evolution of Universes?
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Graduate Why objects at lagrangian points 4 and 5 are stable?
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Anyway, Mysterious Hole on Mars Found
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Graduate Accelerating Universe: Understanding Deceleration Parameter & Implications
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Graduate How Do Black Holes Escape Their Own Event Horizon?
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Graduate Is Our Observable Universe Limited by the Cosmic Horizon?
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Graduate HII Region Temperature Structure
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Graduate What theories appose a multiverse?
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Graduate Question regarding the arrow of time
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Graduate Black hole gravity response question
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Graduate About Hubble Radius (Radius of the Hubble sphere)
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Graduate Do anti-stars emit or absorb photons?
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Graduate Discover the Best Book on Inflation Theory for Your Studies
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High School Seeing the Galilean Moons with Celestron 7x50 Binoculars
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Graduate Does the Friedmann Model Suggest an Unbounded Universe?
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Undergrad A Query on Sun and Moon Coordinate data
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Graduate Are we rewriting the birth of the solar system?
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Graduate Understanding Omega: Baryons, Leptons, Photons and More
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Undergrad What would a black hole look like?
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Graduate What Defines the Universe: Bostrom's Philosophy vs. Hardy's Causaloids?
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Undergrad Astronomy POD: Tan & Blue Galaxies - Why the Color Difference?
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Graduate What kind of energy is released when matter and antimatter collide?
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Graduate What percent of baryonic matter is antimatter?
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High School What colors represent different stages of a star's life cycle?
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Graduate Could Dark Energy and Dark Matter be .?
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Graduate Is Gliese 581d a Habitable Super-Earth?
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Undergrad Measuring the Distances to Stars and Galaxies
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Graduate If two black holes combind together-
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Graduate Is Dark Matter More Significant Than Black Holes in the Universe's Mass?
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Graduate Cosmic Humility: Trillions of Years into the Future
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Graduate Why Should The Atom's Form Exist At All?
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Stargazing Is the James Webb Space Telescope Ready to Replace Hubble?
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High School What Can I See with My Telescope in Boston?
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Who said: however the Earth still rotates
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Graduate Does gravity affect the measurement of pi in non-euclidean geometries?
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Graduate Dark matter searches (a survey of-)
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Undergrad SKA: What's Being Planned & Job Prospects?
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Undergrad Understanding the Doppler Effect: The Red Shift and Our Place in the Universe
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Undergrad Age of Universe: Seeing More than 13.5 Billion Yrs
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Graduate The Ashtekar density (you've heard of the Chandrasekhar mass, now here's )
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Undergrad Interstellar Medium: Est. Mean Mass of Particle
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What Makes Black Holes So Mysterious and Dangerous?
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High School Could Dead Stars Lead to Abandoned Solar Systems?
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Undergrad Supernova 7000 ly Away: Impact on Earth and Light Visibility
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Graduate Accelerating Universe: How Is It Possible?
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Graduate Does 1a supernova release the same amount of neutrino as type2 supernova?
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Graduate Gravitational Waves from Mergers
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Graduate Why Do Stars at the Edge of Galaxies Feel an Inward Pull from Dark Matter?
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Graduate Solar Cycle & Explanation for Recent Changes?
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Graduate Simulating the Future: Great Attractor 100 Billion Years Ahead
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High School Gravitational Lensing: Learn More about Einstein Rings
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Undergrad Learning Physics: How Do Neutron Stars Form?
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Graduate Is the Universe in a State of Universal Motion?
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Undergrad Is NASA's New Evidence the Most Direct Detection of Dark Matter?
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Graduate How Do Accretion Discs and Black Holes Emit High-Velocity Charged Particles?
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Amazing Saturn Photo: Cassini's Awe-Inspiring Image
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LCDM and Cosmology and Cosmologists
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Undergrad Apparent Magnitude: Meaning & 3 Star System
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Graduate A hyperbolicshape of the universe, despite measurements
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Graduate Einstein Cross vs. Ring: Understanding the Alignment of Quasar G2237+030
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Undergrad Gravity and the Rotation of Galaxies
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Undergrad Density of Gliese 581 d: What's the Real Number?
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Could we(entire universe) be almost nothing?
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Graduate Calculating Mass/Density for a 4x Larger Earth
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High School Maximum number of orbiting planets
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Undergrad Why Do Comets Have Elliptical Orbits While Planets Are Circular?
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Graduate Is Too Much Physics Bad For Astronomy?
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Graduate Details on the galaxy crash in our future
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Undergrad Is Pluto's Axis of Rotation Almost Perpendicular to Its Orbit?
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High School Signal Transmission from Mars to Earth
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Stargazing Refracting vs Reflecting Telescopes: Which is Easier to Build?
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Graduate Which Statements about Cold and Hot Dark Matter are Incorrect?
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Undergrad Brightest supernova ever observed
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Graduate What is the true definition of proper distance in cosmology?
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Graduate Cosmology: Is Universe Finite or Unbounded?
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Graduate Is Expansion Force Real or Just a Cosmic Illusion?
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High School Universe Expansion: How Fast Is It?
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Graduate How can tidal friction on Earth affect the Moon?
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Graduate What Are the Possible Changes in the Fine Structure Constant in the Past?
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Graduate Bill Thomson, Harold Jeffreys and Dark Stuff
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High School What is the term for light from the dark part of the moon facing earth
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