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 What is the photon sphere and where is the singularity in a black hole?
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Undergrad Density of Venus' atmosphere - historical
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Undergrad What Makes Gamma Ray Bursts a Fascinating Field of Study?
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Undergrad How can I calculate planet trajectory for a 2d solar system simulation?
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Undergrad Does Higher Luminosity Mean Higher Power in Stars?
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Undergrad Sun's North Magnetic Pole Begins to Flip, South Not Moving Yet
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Undergrad Undergraduate research topic help?
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Undergrad Radio doppler experiment (astro)
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Undergrad Understanding Local Standard of Rest for Astronomy Exam
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Undergrad Limiting Magnitude of CCD Imaging
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Undergrad Why Doesn't the Universe Explode Because of an Antimatter Reaction?
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Undergrad Is it possible to find our Sun's siblings?
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Undergrad Massive Stars Spin Faster: The Reason Explained
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Undergrad Visibility of Venus during the march equinox
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Undergrad Sending a rocket into space 75% less fuel.
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Undergrad Supernova in 2241 BC: Astronomer Views
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Undergrad Why does velocity not vary with distance within 10 Mpc?
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Undergrad What Are Wormholes and How Do They Work?
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Undergrad Is a Utah Petroglyph Evidence of the 1054 Supernova Observation?
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Undergrad Follow-up and pipeline: definitions
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Undergrad Why do orbits become more eccentric when changing speed?
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Undergrad Convective motion and Stellar jitter
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Undergrad Fund ESA's Billion-Plus Euro Project for 2020s Launch
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Undergrad Plank curves and emission/absorbtion spectra
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Undergrad Eccentricity of orbits and gravitational energy
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Undergrad What would happen if the sun was hit by a gamma ray burst?
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Undergrad Why Does Pi Appear in So Many Scientific Equations?
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Undergrad Do objects really take up space?
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Undergrad Unraveling the Mystery of ISM Dust: Origins & Categories
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Undergrad Where do the heavier elements come from, such as those found in planets?
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Undergrad Is the Universe’s Accelerating Expansion Theoretical or Observable?
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Undergrad A few qustions about Dark Matter from a beginner.
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Undergrad When astronomers speculate the distance of galaxies are they talking about its
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Undergrad Dark Energy: Does It Affect All Space?
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Undergrad Why Does the Analemma Show an Ellipse for Solstices?
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Undergrad Revolutionizing Space Travel: The Potential of Dual Space Elevators
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Undergrad Difference Between Plasma and Radiation
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Undergrad First magnetic phenomenon observed on the Sun
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Undergrad Difference Between Solar proton event and Coronal mass Ejection
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Undergrad Can we seek out worlds closer to the center of the galaxy?
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Undergrad Oribtal and rotational velocities
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Undergrad What is our Solar System's orbital plane around the Milky Way?
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Undergrad What causes the variation in Mercury's synodic period?
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Undergrad Celestial sphere and visible stars
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Undergrad How to learn celestial mechanics
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Undergrad The perihelion precession of Jupiter
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Undergrad How can we know/check the sun's current and latest chemical composition?
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Undergrad How much space does a Pound of copper use
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Undergrad What Is the Estimated Number of Homeless Planets in Our Galaxy?
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Undergrad Why Does Titan Have Fewer Impact Craters?
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Undergrad How do low mass stars outlive high mass stars?
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Undergrad Uncovering the Mystery of the Wow Signal: Can We Locate Its Source?
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Undergrad How Does Gravity Work From Earth's Core to the Universe's Edge?
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Undergrad Where Does Kinetic Energy Go During Deceleration?
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Undergrad Velocity determination through redshift
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Undergrad Symmetry of the Universe: Why Doesn't 0 = cba?
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Undergrad How much of an effect does fusion have on a star's gravity?
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Undergrad How is the Barycenter Determined in a Two-Body System?
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Undergrad What are the strange absorption peaks on this solar spectrum?
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Undergrad Calculating distance using redshift
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Undergrad Black Holes, how much energy do they give off?
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Undergrad The proton flux in Solar System in keV range
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Undergrad How do we calculate the magnitude of a system with binary stars?
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Undergrad Launching Spacecraft from the Moon: Is it Worth It?
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Undergrad Orienting Space: 3D Travel from Earth, Center of Universe
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Undergrad Hydrogen and Helium-4 in thermodynamic equilibrium
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Undergrad Question on delta-v and escape velocity?
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Undergrad Understanding Arrays and Their Role in Converting Light into Data
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Undergrad Why do neutrinos escape the sun's core faster than photons?
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Undergrad Venus: Slowing Rotation Detected by Venera, Magellan, and Venus Express
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Undergrad How Do You Convert Proton Flux from 1/(cm^2 s sr) to 1/(cm^2 s)?
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Undergrad Cepheid Variables in Distant Galaxies
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Undergrad Angular Velocity and Spin/Orbital Angular Momentum of Jupiter
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Undergrad How many kinds of force exist between Planets?
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Undergrad Absolute Magnitude Calculation, How?
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Undergrad How Do You Measure Gas Leaks in Space?
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Undergrad When a star loses its mass, do the orbital radii of the planets increase?
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Undergrad Acceleration of spaceships with different masses?
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Undergrad What is the Semi Major Axis of a Binary Star System?
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Undergrad Precession-Jumping from 1875 to 1950
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Undergrad How do Occupants of the ISS Survive a CME
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Undergrad Gyroscopic effect on planetary motion
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Undergrad How massive/hot does a star have to be for fusion to occur
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Undergrad Motions of stars inside elliptical galaxies?
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Undergrad Search patterns in observational studies
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Undergrad Video Games and Their Basis in Theory
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Undergrad The Sun with a planet with a moon with a satellite
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Undergrad Life on Earth: The Future of Humanity and the Impact of Space Exploration
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Undergrad At what volumetric flow rate will air fill a space vacuum at Earth's STP?
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Undergrad Computing the period of a meteor using two ways.
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Undergrad Cracovians Anyone? How do they work?
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Undergrad Finding the position of an object 1800 years ago?
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Undergrad Why Is the JUICE Mission Targeting Ganymede Instead of Europa?
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Undergrad Number of Planets with Circular Orbits: Probability & Science
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Undergrad Calculating Velocity & Axes of Planetary Orbits
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Undergrad The Milky Way from the Andromeda Galaxy: Edge-on, Spiral, or In-Between?
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Undergrad Kepler Exoplanet findings and galactic plane question
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Undergrad How Can I Predict When Venus Will Be Visible as an Evening or Morning Star?
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Undergrad Does outer space just have two spatial dimensions.
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Undergrad Phenomenon of rotation of planets
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