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 Twin Planets Be Visible to Each Other in Altered Orbits?
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What is the value of Mu needed for orbit calculations in the Earth-moon system?
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Is Time Speeding Up in the Expanding Universe?
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How does velocity affects the shape of orbit
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Could a Hollow Supermassive Black Hole Support Life Inside?
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Ever seen a full moon in the daytime?
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Multiple connected topology and gravitation
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Intelligent Life on Mars: MGS Sighting in Sinus Meridiani
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Sky Shade Shift: Does Color Change at Latitudes & Altitudes?
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Dark Matter Particle: Top Candidates
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Transforming Orbital Elements from J2000 to Ecliptic Plane
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Is Landing on Jupiter's Volcanic Moon Io a Viable Possibility?
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What Determines a Star's Life Expectancy?
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What Do Observational Studies Reveal About Dark Matter Distribution?
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History of Universe (Baez timeline)
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Why singularities and not exclusion?
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Are the objects in these pictures related?
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Discover the Connection: Photos That Tell a Story | See the Attachments
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Soemthing for the AE's or anyone else interested in Space
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What's Behind the Shadow of a Crescent Moon?
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Could we see galaxies that were receding faster than the speed of light?
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We always see the same side of the moon
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The Spin of Mercury: 3/2 or 1/2?
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  • Poll Poll
An open letter to the closed minds
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Sun Transit Time: Toronto vs Boston
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My first thread here, about constellation
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How to calculate the time taken for the sun to cool down?
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What are the current hot issues in the standard cosmological model?
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Why does the permeability of free space have an exact value?
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Beginner's Guide to Astrophysics: Get Started Now!
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Why does light/energy propagate?
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What is meant by expanding space
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Calculate the uncertainty of the distance to the clusters?
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Brane Worlds, the Subanthropic Principle and the Undetectability Conjecture
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How Did 19th Century Astronomers Measure the Distance to the Sun?
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Is the matter of black holes in our universe?
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Was All Matter Created During the Inflationary Period After the Big Bang?
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What Is the Frame of Reference for Measuring Velocity?
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Is the cosmos invisible to the unaided eye?
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Origin of the intracluster medium
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Interstellar Gas Cloud: High Temp Mystery
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Pioneer anomaly and quintessence
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What Does It Mean When We Say Our Universe Is Expanding?
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Powered Flight from Earth to Mars - Find Help Here
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Some results from the Hubble Ultra-deep field
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How Do Gluons Affect Neutron Star Stability?
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Moon Moving Away: Why is it Increasing?
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Exploring the Angle of Resolution in the Mercury Transit and Beyond
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Understanding Angular Size: Tips for Determining Object Dimensions
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Galaxy motions -> hidden superstructure (DM)
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Stargazing Picture of Jupiter's moons without a telescope
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Astronaut's Experience Orbiting Earth at 11K mph
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Sunrise from West: The Possibility of a Planetary Shift
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Europe's long term plans for cutting edge astronomy and cosmology research
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Why do stars emit electromagnetic waves?
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Is Our Universe the Result of a Black Hole from a Previous Universe?
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What is the energy of the combined body after the collision?
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Can the Speed of Light Change or Increase?
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Looking for a good title of a book having to do with a blackhole
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What Are the Implications of H. Arp's Red Shift Quanta Theory?
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Is cosmology in constant trouble?
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How Can Beginners Understand Magnitude and Latitude in Astronomy?
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Skywatcher 5.1 parabolic reflector for DSO?
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Humidity and Lenses: What to Do When Too Much Dust in House
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The temperature of empty space What now?
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Statistical superposition of universes
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Is the Kuiper Belt responsible for the subtle slowdown in Bode's law?
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Is the Inflation Theory in the Early Universe Truly Possible?
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Will Longbets.org's Predictions Shape the Future of Sciences and Sociology?
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Understanding Photon Collisions with Solar Sails
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How can we study the composition of the Sun and Jupiter without direct samples?
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Are There "Moons of Moons" in the Solar System?
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Quantized space-time and redshift.
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Does a Black Hole Have a Greater Gravitational Field Than Its Original Star?
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Why do Earth, Moon, and Venus have different numbers of craters?
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Has Gravity Probe B been a waste of money?
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Space vs Energy: Can Volume Exist Without Energy?
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Does Meson Exchange Cease in Neutron Stars at Sub-Femtometer Distances?
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Rubber Sheet, Heavy Sphere & Gravity: Explained
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Could This Be the First Photo of an Extrasolar Planet?
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Do nearby stars have an effect on the Sun and its planets?
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No, this is not a question for biologists.
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Will New Objects Appear in the Sky as Time Passes?
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The Sun's X-file Under The Spotlight
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CIPA - a fantastic Zero Point Energy website
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How Does Infinity Become Smaller? | Hawking
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Mystery of Dark Energy: Unravelling the GR Expansion of Universe
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Was Space Present Before the Big Bang or Did It Expand with the Universe?
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Creating a VB6 Orbit Simulator: Tips & Advice
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Are Cosmic Rays Particles or Radiation?
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Universe Expansion Speed: Einstein's Theory Impacted?
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Cosmic background radiation - alternative proposal
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What do you think will be the fate of the universe?
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Stargazing Did You Guide Your Moon Shot?
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What kinds of space rays are detectable on earth
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What is the formula for calculating delta v for escape velocity?
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I've yet to understand the finite universe
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Chances of aliens finding Earth disappearing
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Black Hole Implosion or Supernova Explosion - Which is More Powerful?
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Strange SETI Signal from ~1000 LY
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