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.
B Why does the moon appear to rock back and forth in the sky?
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I Position and Velocity in Heliocentric Ecliptic Coordinates
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A Two Black Holes' collision thought experiment
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I Understanding Etherington's reciprocity theorem
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B Are galaxies part of constellations?
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Mathematical Proof of Kepler's First Law of Orbits
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A Viewpoint: Black Holes Produce Complexity Fastest
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I How to calculate day length of a tidelocked double planet?
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B Why doesn't the Moon get pulled into the Earth?
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B How Much Should You Spend on a Moon Filter?
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I Pluto's interaction with solar wind
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Stargazing Large Sunspot Visible: See it Now for 3-4 Days - 13 Apr 2016
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A Will this setup work for backyard photometry?
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I The universe doesn't have volume from outside?
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I New light shed on birth of the universe
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Kid Didn't Discover Lost Mayan City via Astronomy After All
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I How Will Nano Spacecraft Reach Alpha Centauri?
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I Space Debris: Questions from a Newbie
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I Discovery of how to measure wavelength absorption lines
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I How Small Can a Mass Be Squeezed?
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B What are the name and function of this apparatus
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B What do you call rocks that don't orbit the sun?
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A Is there proof that black holes really exist?
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Stargazing Did You Catch These Amazing Stargazing Moments This Weekend?
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B What are the biggest misconceptions about black holes?
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B "Without Earth's atmosphere, cosmic rays would be lethal"
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B Calculating Orbital Velocity in 2D
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B Kepler Telescope Running in Safe Mode
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B Did Stars Precede Life in the Universe?
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B Gravitational Collapse: Internal Energy & Potential Energy
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I Could it be so easy? (Why is space three-dimensional?)
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B Potential Organism Sustaining Planets
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I Where Can I Compare Star Spectra?
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B How to contain an atmosphere in space?
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B Does a magnetic field accompany Jupiter's Great Red Spot?
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I Evidence to support the theory of stellar nucleosynthesis?
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I Hawking radiation and energy-negative energy pair production
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I Comparing Earth's diameter with Moon's diameter
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I Star Radius & Mass from Spectral Class, B-V, Luminosity
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I How can I calculate red shift for intragalactic bodies
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B How Can I Improve Pointing and Eyepiece Quality on My Dobsonian Telescope?
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How much of the visible universe have we explored?
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A April 23rd Magnetosphere Anomaly
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B Is the Big Bang a Result of a Spontaneous Singularity?
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A Mars as Second Earth: Slowing Down Its Orbit
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I Could "reverse entropy stars" exist in our universe?
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I Does Space Compressibility Affect the Big Bang?
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B What is the source of the mysterious red rectangle in space?
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I Meteor impact and axial tilt, relation to climate
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B Universe Expansion: Is Earth Spinning Away From Sun?
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B Fermi Paradox: What are your opinions on the Fermi Paradox?
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B I've done it the wrong way roundn
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B Is Earth's Movement Away from the Sun Impacting Global Warming?
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I What does cosmological redshift do to light
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I Calculating average density of the Universe
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A "Observation" of Black Hole Merger
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B How important is gravitational red/blueshift for stars?
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I Factor of how much linear size scale has changed
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B The Fate of Gaseous Planets: Can They Stay Stable Forever?
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Stargazing Facing difficulties with radio telescope measurements
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B What would happen if the Sun collided with a similar star?
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A Two Way Tidal Lock: Can Planets and Moons Sync?
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B The way the moon 'behaves', coincidence or 'something more'?
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Stargazing Software to adjust exposure? webcam, astrophotography
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A Gamma ray burst associated with LIGO GW event
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Stargazing Double image in reflector telescope
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I How Can We Visualize One Dimensional Strings in Space Time?
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B North & South Star: Polaris & Sirius
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I Planet at barycenter of a binary system.
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I How would one know whether a star would be observable?
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B How does dark matter affect planetary motion?
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How Small Was the Big Bang Singularity When It First Exploded?
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B Why the Earth orbits around the Sun
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B Lowest/Highest mass of a star, star system
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B Unraveling the Mystery of Dark Matter: Is it a Different Type of Gravity?
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I Why there are different size stars?
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B Questions about the lifespan of the Earth
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B How to calculate the distance between a Star and Zenith
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A Black Hole Paper Outlining Process of Singularity Formation
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Are there widespread misconceptions about degeneracy pressure?
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B Can Living in Space Lead to Immortality Through Technology?
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B Does antimatter have positive or negative mass?
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B Can Cosmic Strings Align Black Holes?
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I How Does Aerobraking Work for the ExoMars Orbiter?
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B Can we see individual stars in the Andromeda Galaxy?
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B How Does Stellar Parallax Measure Distance?
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I Question about the cosmological constant
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B Initial Impetus Needed for Curved SpaceTime?
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B The Falcon Landing: How Did They Do It?
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B What Are the Implications of Space Being the Ideal Medium for Light?
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I KELT-4Ab Orbital Characteristics
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B Is Extra Terrestrial Life Possible in This Universe?
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I Is an Aragoscope Currently in Use?
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B Binary/Ternary Systems: Could Stars Orbit a Non-Stellar Central Object?
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B What can I expect to see with a 6inch mirror?
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Stargazing Is a Telescope for Asteroids the Key to Discovering New Main Belt Objects?
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A Variance of mass inside a black hole
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B Binary Stars Observable with Binoculars: Periodicity
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B Can Space-Time Rip? What Causes Tears & Healing?
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A Are we now alone in the Universe?
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