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.
Could Quantum Gravity Predict a Long-Distance Invariant Scale?
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Planets Orbit Sun: Why Same Direction?
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How Fast Is the Milky Way Moving Relative to the Cosmic Background Radiation?
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Could Geostationary Satellites End Up Gathering Over the Indian Ocean?
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Could Sedna be a trapped rogue planet
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Mysterious signals from 1000 light years away
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Star formation and distribution in spiral galaxies
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Is the Orion Trapezium Exploded from a Pre-Stellar Body?
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Flat geodesics mediate spacetime
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Possible terrestrial extrasolar planet found
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Question: Jupiter and Saturn at 200x?
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Entropy of a Star: Calculating Sun & Neutron Stars
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You Are the Centre of the Universe
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Expert Help on Understanding Seasons with Perpendicular Earth's Axis
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Should PF Have a Separate Quantum Gravity Forum?
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Stargazing What Telescope Should I Buy Under $700?
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Curved or Flat? Decoding the Distance Measurements in Space
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Is the Parallax Method Still the Most Widely Used for Measuring Star Distances?
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Weightlessness in the Center of The Earth?
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Your weight on a Space Elevator ?
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Stargazing Looked through a telescope for the first time
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Why Do Variable Stars Like R Hydra Exhibit Unique Color Changes?
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Can dark energy prevent neutron stars from collapsing into black holes?
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Unruh: Loop Quantum Cosmology paper (new)
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Burning Man 2004- The Vault of Heaven
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Searching for Aliens: Are We Alone in the Universe?
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Is G truly a constant in the equation F(M,m,r)=GMm/rr?
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QG plasma and gamma ray bursters
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Neutron Star Properties: Density, Pressure, and Acoustical Velocity
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Building an Observatory for Your Astronomy Club: Tips and Considerations
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Are there multiple theories for the origin of dark matter and dark energy?
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Why Does Gamma Ray Take 1M Years to Reach Star Surface?
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Is the Moon's Gravity Calculation Correct?
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On the general curvature of space.
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Does Universe Expansion Influence Galaxy Clustering?
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Why do Mercury and our Moon not spin?
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Origin of Cosmic Rays and GRB (new paper by A.Dar)
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Stargazing Schmidt-Cassegrain Telescope Image Quality - Karl's Questions
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What Does Newton's Gravitation Constant Represent?
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The Denouement of Blue Supergiants
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Formula for sunset/rise times, moonrise/set and phases
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Baez on Dark Energy vs Cos.Const.
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Doppler Effect: Does Light Obey the Rule?
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What is the significance of the Chandrasekhar boundary in neutron star research?
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Three Dimensional Space in the Forth Dimension
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Expanding & Contracting Universe: Black Hole Integration?
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The Solar Phenomena: Prominences, Flares, and CMEs
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Everything you wanted to know about Dark Matter
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Why does light travel at light speed?
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Is the nature of space and time still a mystery?
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Stargazing Build Custom Telescope Mount: Tips & Advice
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Stargazing What was the first object you saw through a telescope?
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Is the Universe Closed, Flat or Open?
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City-Sized Asteroid to Pass Earth This Fall
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Able to catch the meteor shower this morning
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The Colors of Stars: Why Are Some Red and Others White or Blue?
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Is Space Merely a Manifestation of Matter and Energy?
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Furthest Point on Earth from the Center: Mt Chimburazo, Ecuador
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Is Research on Gravity Lifts a Step Towards Defying Gravity?
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How do we detect x-rays from the center of our galaxy?
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Hubble hit by instrument failure
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Dark Matter & Gravitational Effects on Galaxies
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Is Isaac Asimov's Moon-Planet Theory Valid?
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Is Bush's Vision for Space Exploration Grounded by Budget Cuts?
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Stretched space far from our own
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Why Are We Orbiting Earth Instead of Landing on the Moon Again?
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How was time and space created at the Big Bang?
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Final project - fate of the universe - need ideas
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What caused the planets to aggregate as they did?
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Why the Moon Looks Big at the Horizon and Smaller When Higher Up.
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Calculating viewing times of satellite from groundstation
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Black holes do not collapse to singularity>
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Have you witnessed a dazzling Iridium flare in the night sky?
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Stargazing Best telescope for a young astronomer under $750?
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The Hawking Effect: Unruh-Schutzhold Paper
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Could Superluminal Light Speeds Impact Theories on the Universe's Cold Death?
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Favoured theory for planetary formation
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What was the Maximum Energy Density at the Onset of the Big Bang Expansion?
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Supernova Ignition: Does Blackhole Mass Influence Star Formation?
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Explaining B-Field of N-Star: How Neutron Stars Have Magnetic Fields
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Vacuum energy in gravitational fields
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Probability of Intelligent Life in Our Galaxy
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Hawking Radiation: What it is and How it Relates to the Schwarzschild Radius
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Space as a vacuum and earth's atmosphere
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The most significant, immediate relic of primordial quantum mechanics?
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What came first CYBERSPACE or OUTERSPACE?
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Could Other Universes Exist Beyond Our Own?
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Understanding Type II Supernovae: N-Star vs. BH Supernova Explained
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Is the existence of Hawking Radiation compatible with the Big Bang theory?
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Explaining 4D Space-Time in Simple Terms
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Determining a Planet's Age Based on Mountain Ranges
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Why do neutron stars have magnetic fields
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What Is the Substance of Space and Its Role in Our Perception?
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What mass is lost after a hypernovae?
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Dark energy + missing antimatter
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Explaining Singularity: A Beginner's Guide
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Determining orbits from R.A., Dec, & time
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Steven Hawking / MKaku. Who's right about Black Holes?
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Black Holes: Comparing Hawking & Kaku Theories
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Observational Difference Between Neutron Star & Black Hole
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