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.
Undergrad Textbook on Mathematical Astronomy
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Undergrad Elliptical orbits and focal points
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Undergrad Help with Orbital Mechanics: First Post
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Undergrad What Is the Gravity Value on Neutron Stars?
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Undergrad Help with Spectroscopy in Astronomy
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Undergrad Unraveling the Mysteries of the Expanding Universe: Age and Size
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Undergrad Chance of Planet Formation without Stars
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Undergrad Why most of the planetary orbits are ellipitical?
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Undergrad A hypothetical space elevator question.
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Undergrad Planets <-> solar systems <-> galaxies
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Undergrad What equations are needed for calculating Keplerian orbital mechanics?
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Undergrad What Would Happen if You Cut the Earth in Half?
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Undergrad Find Accurate Weather Logs for Your Astronomy Observations | Natski
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Undergrad How Far Can a 300 mm Telescope Resolve a Double Star Separated by 10 AU?
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Undergrad Changing Earth's Rotation: Impact on Gravity and Mass Loss
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Undergrad Age of Stars: Calculating & Assessing Helium
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Undergrad Stars and planets made out of antimatter?
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Undergrad Gravitational Attraction: Could Dark Matter be Explained?
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Undergrad How can you estimate mass of star?
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Undergrad Books on Astrophysics/Nucleosynthesis
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Undergrad Does Earth's eccentricity change?
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Undergrad Does the Cosmos Have a Preferred Direction?
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Undergrad Astroid Toutatis year 2012 has effects on Earth and moon
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Undergrad Measuring Sea Level: Tides, Elevation & Distance from Earth's Center
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Undergrad What Catastrophe Could Render Earth Uninhabitable in 40-60 Years?
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Undergrad Sidereal Time: Clarifying Contradictory Definitions
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Undergrad Can Light Really Be Trapped by a Black Hole?
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Undergrad Why is it difficult to imagine nothingness and infinity?
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Undergrad Does Doppler effect change the energy of emitted light?
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Undergrad Why Are Galaxies Accelerating Away?
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Undergrad Is there something that Sun actually absorbs?
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Undergrad How can I calculate the tilt of the Earth using trigonometry?
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Undergrad Is our Solar System a large Atom?
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Undergrad Is There Ice on Mars? New Evidence from Fresh Meteorite Craters
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Undergrad Water on the Moon: New Science Express Discoveries
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Undergrad Star Catalogs within 200 LY of Earth - Needed in Table Format
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Undergrad Why does Saturn's dust form a flat ring and not a sphere around it?
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Undergrad Which statement is true about Redshift and the Hubble constant?
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Undergrad Dark Matter: How Do We Know It's Not Just Invisible Planets?
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Undergrad Is Redshift Possible in a Stationary Universe?
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Undergrad How Does Gravitational Force Influence Ocean Tides?
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Undergrad How do we determinate the mass of stars
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Undergrad Is or can gravitational force become cumulative?
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Undergrad Other planets interaction on Earth-Moon System
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Undergrad Question about origins of elements
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Undergrad Japan building space-based power plant
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Undergrad Evolution of Our Sun's Rotation: From 4.5 Billion Years Ago to Present Day
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Undergrad Question of Galactic Proportions
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Undergrad Dark Matter: What Is It & How Was It Formed?
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Undergrad If a comet kicks the moon out of its orbit and away from earth
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Undergrad The Pioneer Anomaly: Examining Velocity Gained through Gravity Assist Manoeuvres
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Undergrad The Mystery of WASP-18b: Uncovering the Mass and Rotation of Its Mother Star
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Undergrad What Holds People on Earth if Gravity is the Spacetime Fabric?
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Undergrad Moon-Earth distances and interactions
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Undergrad Why Are Orbits Elliptical? Rules of Circular Motion
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Undergrad Can a Telescope See Itself from 100km Above Earth?
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Undergrad Solving Brightness Equation with Procyon: 7L☉ and 11.41 light years
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Undergrad Light Speed in Vacuum: What's the Significance?
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Undergrad Why Isn't a Collapsed Star a Black Ball?
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Undergrad What are the types of waves that can travel through space?
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Undergrad Why can't light escape a black hole?
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Undergrad Black holes and conversation of energy
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Undergrad Can Solar Storms Render All Electronics Useless?
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Undergrad Why is the moon drifting into space
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Undergrad Joining two orbiting space vehicles
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Undergrad Spectra Classification: Finding Sources for Stellar Objects
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Undergrad Is There a Center of Mass to the Universe?
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Undergrad Difference between a red/blue shifted object and one in rest.
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Undergrad Does Light Slow Down During Long-Distance Space Travel?
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Undergrad What is the relation between redshift and absorption lines in galaxies?
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Undergrad Energy time relationship from an observer in space
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Undergrad Hawking Radiation: How Do Black Holes Emit?
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Undergrad Why Don't Heavier Elements Sink to the Sun's Core?
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Undergrad The Expanding Universe: Understanding Hubble's Law
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Undergrad Difference between Thermal and Kinetic Energy
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Undergrad How to find the position of a star in the sky
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Undergrad Bigbang and its light coming to us
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Undergrad Satellite is in low orbit around the Earth
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Undergrad Can Centripetal Force create Gravity?
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Undergrad Can we use paramagnetism to create a magnetic field on Mars?
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Undergrad Supernova explosions element detection.
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Undergrad Interesting astro/phys question I'd like the naswer to
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Undergrad Why don't stars in a cluster clump?
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Undergrad How Can We Understand the Concept of Universe's Temperature?
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Undergrad Counting Stars in Universe: How Big Bang Began
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Undergrad Mercury's Tidal Lock & Eccentric Orbit Explained
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Undergrad Can We Build a Shaw-Fujikawa Translight Engine for Space Travel?
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Undergrad Black Holes vs Wormholes: What's the Difference?
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Undergrad Is a black hole considred a black body?
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Undergrad Yahoo: Earth-Venus smash-up possible in 3.5 billion years: study
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Undergrad Black holes - a few questions from a newb
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Undergrad Help sought - data on intergalactic distances
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Undergrad Harnessing Energy from Outer Space - Solar, Nuclear & More
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Undergrad So how fast are we actually moving?
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Undergrad Why does the sun have non uniform distribution of magnetic fields?
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Undergrad Determining the individual magnitudes of two stars
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Undergrad Why is space so afraid of matter?
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Undergrad How can the small angle formula be used to measure the physical size of a star?
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Undergrad How would a man on earth appear from outer space
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Undergrad Interstellar Gas & Dust, Densities & Temperatures
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