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.
Is the Oort Cloud Large Enough to Encompass a Multi-Stellar System?
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What Are the Orbital Periods of Binary Pulsars?
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Can We Still Receive Images from Voyager Probes?
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Belelgeuse turning into a supernovae
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Singularity in Astrophysics: Meaning & Etymology
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I have been told space and time are illusions. What does that mean?
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A question about star's luminosity, temperature and mass.
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Is Mars' Metallic Core Possible With a Mean Density Lower Than Earth's Mantle?
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Where does the heat of super-nova end up after black hole formation?
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How Do Spiral Galaxies Maintain Their Shape?
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How sure can we be of the distances in the solar system?
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What was the first mineral formed in the universe?
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How many dimensions are there in a black hole
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Viewing the Sun and Planets from the Asteroid Belt
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Birth of a Planet: The Formation & Heavy Elements
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Who Is Right About the Sun's Position and Size?
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Neutron star spin and rotation axis
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Do We Really Understand the Singularity?
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Why Do Planets Except Mercury Rotate in Same Direction?
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What is the composition of the crust and atmosphere on a neutron star?
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Thanks for the interesting article.
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How much did Earth's gravity alter the course of 2005 YU55?
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Is the Notion of Public Space a Myth?
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What causes this shell of light around the Earth in this vedio?
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Stargazing What are the limitations of astrophotography and how can they be overcome?
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How long would daylight last on Earth if the sun disappeared?
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Kinetic energy of gases in stars
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Astrobiology Missions, whats being proposed?
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Can anyone tell me the basics of Quasar?Note: Means that how it is
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Spotting 2005 YU55: Instructions & Speed Info
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Can variable stars become quickly non variable and viceversa?
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Could women be better suited for long distance space travel?
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Can Astronomical Objects Orbit Around Satellites?
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Energy savings with space elevator
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Number of stars within 150 light years of us?
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Light Pollution & National Dark Sky Week
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The Big Bang and CP Violation: Where Did the Mass Go?
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Does Fine Structure Constant Vary From Place to Place?
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Which elements/compounds can be liquid on Venus?
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How Can I Identify Elements in Jupiter's Absorption Spectrum?
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Measurement of Galaxy Rotation: How Long Does it Take?
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Running in Space: Can You Accelerate?
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How feasible you think Nemesis theory is
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Stargazing Quick and Easy Telescope Measurments?
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Determining the dominant body in a basic planetary system simulation
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Stargazing How can I safely view a solar eclipse?
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Solar system on my date of Birth
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Is the Universe Losing Mass Through Stellar Energy Conversion?
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What is the best book on cosmology for all levels of knowledge?
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Is the Center of the Milky Way Not What We Think?
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Black holes, dark matter, the expansion of the universe, and unifying theories.
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Possible energy sources that a lunar base might have as an option
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Are orbital planes generally parallel on large scales?
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Why Only One Sun & Moon on Earth?
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Uncovering the Mystery: Has Something New Been Found?
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How to Accurately Convert FK5 to Altitude and Azimuth?
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What distance will a traveler cover if they walk in a southwesterly direction?
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Virgin Galactic - the first step?
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The size of the universe, and what we can see.
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Why aren't stars in a star cluster attracted to each other?
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We Know Less About CDM Than We Did Before
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What Are the Potential Benefits of a Lunar Base?
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Will Pluto Crash into Neptune?
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Question: Regarding Stellar Spectroscopy Equipment.
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Gravitational Lenses & Light Frequency: Same or Different?
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How to simulate planets orbit curce around the sun ?
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Is Velocity Consistent in Planetary Orbits?
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Stargazing Choosing a Telescope: Orion vs Celestron
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Formation/Expansion of Red Giant
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Can a spaceship land on a pulsar?
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Is Dark Matter Just Unseen Water Vapor?
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What is the estimated energy output of the Milky Way?
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A question based on Lawrence Krauss' explanation
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What if light speed wasn't the limit?
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Why are galaxies shaped like spirals?
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What are some applications of lasers in astrophysics research?
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Star to black hole same mass/gravity?
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Questions about Galactic Rotation
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What is the Smallest Possible Size of a Black Hole?
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Is Gliese 581d a Goldilocks planet?
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What would Fermi say now about his 'paradox'?
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Why are planetary orbits so circular?
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What is information in a black hole
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Why doesn't tidal force pull earth and moon together?
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Neutron Stars vs Black Holes: What's the Difference?
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Theoretical scenario for star-forming with a calculation
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Why most of the galaxies are having two spiral arms only?
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Explore Manhattanhenge – the Manhattan Solstice
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What are the main challenges in developing space-based solar power systems?
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Light travel paradox? Please, help to figure it out
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Soft landiing an asteroid at the south pole
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State Space control dervatives of input in B matrix.
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Ptolemy reduces to Kepler as Epicycles → ∞?
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Does the Universe Have a Center of Mass and Why Is It Expanding?
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Using Black holes to view our solar system
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Understanding Very Long Baseline Interferometry: Is the Formula the Same as #2?
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Increasing the mass of the moon (via pancake theory)
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What Causes Early Convective Instabilities in Supernova Explosions?
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Stargazing Why are Radio Telescopes less detailed?
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Stargazing Telescope for my astronomy class next semester
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