Astronomy, Astrophysics, Cosmology Forum

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Join in expert discussion on the topics of Astronomy, astrophysics and cosmology. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Undergrad Were paths of Voyager craft lucky to get out of the heliosphere?
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Undergrad Is the total energy of the observable universe constant?
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Graduate Future of the electron neutrino mass limits
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High School Looking for opinions on YouTube Fermilab videos
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Undergrad Europa Clipper Interplanetary Mission
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Undergrad Relationship between collision and relaxation
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High School Distance traveled by light accounting for expansion
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Undergrad New measurement of the Hubble Parameter
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Graduate Gas around the black hole of galaxy M87
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Undergrad "It from Bit" and the multiverse?
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High School Universe rate of expansion: speeding up or slowing down?
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Undergrad Distance using Cepheid variables
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High School Rate of the expansion of the Universe and the Big Bang
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If you could see gravity what do you think it would it look like?
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Undergrad Solving the Horizon Problem: 1 Source or 105?
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High School Is the Gamma Ray Burst Diameter Wide Enough to Engulf Our Solar System?
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High School The Physics of a Black Hole Merger: What Happens to Mass?
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Undergrad Is there a radial gradient of redshifts within individual galaxies?
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Undergrad Why are planets visible in a telescope in the daylight?
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Undergrad Did Wheeler consider Carter's anthropic multiverse?
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Undergrad Does Spatial Curvature Falsify Eternal Inflation?
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High School Our universe was connected to another universe?
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Undergrad Discrepancy in Hubble's "constant" and its implications
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Graduate Equilibrium point of matter and radiation density
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High School Questions about cosmic background radiation
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High School What is the size of the observable Universe?
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High School Age of the Universe at the recombination?
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High School Age of the Universe vs Age of the Stars
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Undergrad Any direct measure of Universe expansion via galaxy subtended angles?
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Graduate Part of the Hubble discrepancy can be explained by local underdensity
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Graduate The Habitable Exoplanet Hunting Project
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Undergrad Deflect Asteroid w/ Collisions: Calculating Theta & MJ Interractions
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High School How to calculate a star's luminosity/radius
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Graduate Friedmann-Robertson-Walker Models
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Undergrad The Symmetry of Angular Momentum Conservation
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Undergrad CMBR & Flatness: Mapping Universe Flatness?
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Stargazing Two White Dwarfs in a seven minute mutual orbit
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High School Resources to help understand black holes
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Graduate Is the Hubble Constant Truly Constant?
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High School Is the Instantaneous Expansion of Space-Time Possible?
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Undergrad Did Planet 9 and Neptune Cause Uranus' Tilt?
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High School Is the Milky Way Warped? New 3D Map Reveals Surprising Findings
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Undergrad What is Earth's future warming due to the Sun's increasing luminosity?
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Undergrad On Hubble's constant, the expansion of the Universe and vacuum energy
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Undergrad How much worse is the location of La Palma vs. Mauna Kea?
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High School Experiment involving Kepler's laws
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Stargazing Mysterious Phenomenon Seen in the Night Sky
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Graduate Resolving power of a radio telescope array: Quantum or classical?
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Stargazing Two moons, two different rotational paths around a planet?
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Undergrad What is the Maximal Parallel Velocity of a Satellite in an Elliptical Orbit?
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Undergrad Free Orbit Insertion: Is it Possible?
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Undergrad How Can We Interact with Dark Matter for Sci-Fi Novel?
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Undergrad What do "marginalized" or "marginalized error" mean? (contours - posterior)
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Undergrad Does the Strong Anthropic Principle have any equivalent specific model?
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Undergrad Are dark matter and dark energy caused by same phenomenon?
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Undergrad E- & Ions Deflection by Earth's Magnetic Field
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Stargazing CApollo 11 50th Anniversary: CSPAN3 Coverage Today
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Undergrad Some redshift from prism effect of a gravitational lens?
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High School Questions regarding expansion, the vacuum in space, and black holes
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High School What would happen if the core of the sun were removed?
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Undergrad Earth’s Magnetic field formula or downloadable vector field
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Graduate Probability distribution: exponential of a quartic
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High School Cloud Cities on Venus: Viability & Feasibility
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Undergrad Fraction of solar systems with an Earth-moon configuration?
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Undergrad New table-top gravitational-wave detector proposed
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High School When could life theoretically exist in any star system after the Big Bang?
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High School Can Hypothetical FTL Technologies Enable Travel to Other Bubble Universes?
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High School What is the important scale of things in the Universe?
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High School Dark Matter & BAO: How Does it Suppress Baryonic Oscillations?
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High School Thirty Meter Telescope can resume construction
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High School Examples of theoretical proofs overturned by evidence?
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Undergrad Chameleon Theory: Detecting the Particle with Astronomical Surveys
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Undergrad Question about the Cosmological Constant
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Undergrad Is the Solar Constant Really 340 W/m^2 or 680 W/m^2?
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Undergrad Can Satellites in Frozen Orbits of the Moon Study Different Ground Areas?
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Undergrad What is the geometric plan for ALMA?
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Undergrad Can the LIGO observatories detect (with accuracy) temblors?
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Undergrad Formula for the large-scale bias of galaxies
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Undergrad Is Infinity Possible Within Our Finite Universe?
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Undergrad Hubble's law and conservation of energy
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Undergrad The laws of thermodynamics and the Universe
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High School How Is Methane Disappearing from Mars' Atmosphere?
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High School What is responsible for the spinning of a galaxy?
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Graduate Forecast with Fisher formalism : loss or gain of information
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Undergrad How can an asteroid get caught at a Lagrange point without a "brake"?
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High School Why do pictures of stars have 4 cardinal points?
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High School Do planets without a solid surface precess?
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Graduate Determine whether A is orbiting B
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Undergrad Amount of energy inside a sphere of radius 1au around the Sun
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Stargazing Event Horizon Telescope Results Released Yesterday (April 10, 2019)
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High School Particle Deceleration in Relativistic Jets?
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High School How do we know that the Universe is expanding?
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High School What process allows us to 'see' lightyears of distance with the natural eye?
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Undergrad Does the gravity sling require rocket guidance to be non-negligible?
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Undergrad How was the Earth's Orbit Derived?
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Graduate How Does Rotational Velocity Affect Gravity and Space Launches?
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High School What is our understanding of dark matter?
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High School Can someone please explain this paragraph from A Brief History Of Time
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Undergrad SpaceX's 5K Satellites: A Risk of Man-Made Meteors?
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Undergrad My 3rd question - About Stellar Spectrum
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