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.
Graduate Zero-Energy Universe Hypothesis: Questions & Answers
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Undergrad Map or a Listing of All the Constellation Boundaries in Right Ascensio
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Graduate How many dimensions are there to space time?
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Undergrad Expanding universe, big bang question
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Graduate Cosmic Redshift & The Redshifted Photon
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Graduate Is 16.4 GHz a Significant Frequency in Radio Astronomy?
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Undergrad Calculate Area of Ellipse in Keplerian Orbit
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Graduate Are the Parameters for Calculating the Age and Size of the Universe Different?
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Graduate Expansion by doppler (red) shift
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Graduate Could a Rotating Supernova Cause Another O-S Extinction?
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Graduate Does Gravitational Time Dilation Impact Cosmological Age Estimates?
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Graduate What Are the Community's Theories on Dark Matter?
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High School Can Astronomers Predict when a star will explode?
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Graduate The big crunch effect on entropy and time
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Graduate Unraveling the Mystery of Dark Energy in the Expanding Universe
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High School Is it true that if two pieces of metal touch in space
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Graduate Can Dark Matter Radiate Heat or Form Black Holes?
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Graduate Dark Matter. Space-Time curvature. Galaxy formation
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Undergrad Is a black hole black from all directions?
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Graduate Can the universe be both infinite AND expanding
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Undergrad Why do all the planets orbit in the same plane?
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Graduate As I Was Looking At A Strange Black Hole Image I Wondered
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Undergrad Can Gas Giants' Atmospheres Ignite Without Oxygen?
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High School How long could life on Earth survive if the sun went out?
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Undergrad Geocenteric Equatorial Coordinates of the Sun
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High School Chelyabinsk Meteor Strike: How Bright Was It?
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Graduate True map of universe from computer simulation with CMB initial state
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Undergrad Do we live in a black hole(or an white hole)
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High School Can a planet have different levels of gravitational pull
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Graduate Is there radiation colder than the CMBR?
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Graduate Making new sense of the three-body problem
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Graduate Answer: Find Second Moment of Mass & Energy for a Taurus w/E=mc2
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Graduate Who Determined the Phase and Period of Epicycles in Greek Astronomy?
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Graduate Are There Documented Polarities in Comets' Magnetic Fields?
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Graduate Rational ratio of frequencies leads to isolating integral of motion
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Undergrad How do we know the orbits of the planets?
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Graduate Why is the CMB Visible if Younger Light Sources Are Not Yet Visible?
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Undergrad Creating an equation of a 2D path of an orbit
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Undergrad The Most Distant Star in the Milky Way
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Undergrad Perfect Full Moons" - Find Date & Place to See Rare Celestial Event
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Graduate Our universe may have emerged from a black hole in a higher-dimensiona
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Graduate Conservation of mass and black holes
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Graduate Energy of an Expanding Universe Decreases?
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Graduate Dark matter = ligh energy, Dark Energy = also light energy?
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Undergrad Question about space travel and the human body
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Graduate Unidentified emission line in Galaxy Clusters
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Graduate Direct detection of dark matter?
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Graduate Is the big bang actually a white hole?
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Undergrad What is Specific Intensity in Astrophysics?
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Stargazing Cleaning a Telescope's Mirror: Tips and Techniques
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Stargazing Designing a Telescope: What Equations Do I Need?
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Graduate Need help finding exact time of planet aspects with Jean Meeus library
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Graduate Minkowski Space: Can Objects Have Same World Line?
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Graduate Black Holes & Infinity(Singularities)
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Graduate Calculate Interstellar Rock Orbit in Solar System
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Graduate Origin of Dimensions: Evidence of Order or Big Bang Simultaneity?
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Graduate Solar Gravity: Is There Good Data?
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Graduate Question regarding the universes origin
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Undergrad Why does'nt SUN burst like a baloon and collapse?
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Graduate Infinite universe but finite beginning?
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Graduate Gravitational effect of virtual particles
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High School Scale of the universe if a star was a grain of sand
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Graduate Can black hole entropy be observer-dependent?
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Graduate How many gravitons are there in the observable universe?
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Graduate Variational Principle for Spatially Homogeneous Cosmologies/KK-theory
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Undergrad Does Aluminum Coating on Telescope Mirrors Turn into Aluminum Oxide?
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Graduate What happens to the energy when the universe dies out?
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Undergrad Calculating latitude and longitude at any time
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Did Humans Go to the Moon? A Debate
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Graduate Could Space Topologies Unify Matter and Energy in a Curved Cylinder Model?
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Graduate What is Kepler-70b's surface like?
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Undergrad Could our solar system exist 100x bigger?
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Graduate Would tardigrades survive on Titan?
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Graduate Does Inflation Theory Exclude the Impact on Temporal Dimension?
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Graduate Calculating Artificial Gravity for a Rotating Space Station
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Undergrad Any dates/venues of lectures in the UK?
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Graduate Black Holes in the center of galaxies
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Undergrad What are some recommended books on white dwarf stars?
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Graduate Atmospheric Transmittance Venus?
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Graduate How do they define luminosity function in astrophysics?
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Graduate What is the Lorentz transformation
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Graduate All About the Einstein Field Equations
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Graduate What is the Mass–energy equivalence
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High School What are Trojan Asteroids and How are They Named?
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Undergrad Synodic Period: Definition & Equation
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Undergrad Sidereal Periods: Definition, Equations & Examples
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Graduate What is a Photon Sphere: Definition and Properties
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Undergrad What is the Mathematical Definition of Orbital Eccentricity?
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Graduate What is Laplace-Runge-Lenz vector
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Undergrad Kepler's Laws: Definition & Equations
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Graduate What is Irreducible Mass in Black Hole Physics?
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Undergrad What is Irradiance? Definition, Equations & Explanation
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Graduate What are the effects of Hawking radiation on black holes?
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Graduate What Describes the Expansion of the Universe?
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Graduate What is the Friedmann acceleration equation
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Graduate Frame Dragging: Definition & Equations
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Graduate What is the Critical Density in the Context of Universe Expansion?
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Graduate What Are Closed Timelike Curves in Black Holes?
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Graduate What is Mass Inflation? A 5 Minute Introduction
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Graduate How Does Binet's Equation Determine Acceleration in a Central Force Field?
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