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 Correct Physics for Fictional World
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Graduate How confident are we of the neutrino CMB energy density?
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Undergrad Are we at the center of the universe and whats at the edge?
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Undergrad What Determines the Size and Growth of a Black Hole?
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Graduate Collisional Astrophysics Models for Computer Scientists
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Graduate What Is Beyond The Observable Universe?
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Undergrad Why is the edge of the universe the place to look for the oldest stars?
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In Big Bang Theory (the show) what are their jobs?Serious
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Graduate What does a black hole look like from behind?
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Graduate Lunar solstice when the Moon's Equator crosses the Zero Plane of the Earth
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Potential Cancellation of the JWST
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Undergrad Objects in orbit are weightless?
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Graduate If somehow a supernova will be redirected to 30, 45, 60, 80, 90
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Graduate Understanding Singularity: Zero Mass, Infinite Density
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Graduate Quantum mechanics and black holes
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Graduate Magnetic bubbles at the edge of the solar system and CMB
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High School How Does Gravity Influence the Movements of Planets and Moons?
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Best location for stars with naked eye
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Undergrad Is Iron the Ultimate Killer of Stars?
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Graduate Elliptical Orbits (Using Newton's Model)
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Undergrad How Is Andromeda Approaching If Space Is Expanding?
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Graduate What Form Did Matter and Antimatter Take During Annihilation After the Big Bang?
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Graduate Is a Grand Unifying Theory Possible in an Evolving Universe?
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Graduate Hello PF.I would like to get your view on the plausible scenario
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Graduate Was the Early Universe Truly Homogeneous?
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Undergrad Is the Mass of the Universe Accurately Represented in Astronomy Magazine?
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Graduate Gravity modelling of asteroid 433 Eros. Any help will be appreciated.
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Graduate Intergal result and quantum cosmology
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Graduate Quantum mechanics and General Relativity overlap
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Graduate How Do Acoustics in Space Affect Communication with Other Civilizations?
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Stargazing How Do Telescopes Show Us Distant Objects in Space?
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Graduate Can measurements of red shift be affected by the shape of spacetime?
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Undergrad The Force of Space: Dark Energy and Its Impact
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Undergrad NASA Space Shuttle Launches iPhone to Test Radiation Effects
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Undergrad Researching to Become a Theoretical Astrophysicist
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Graduate What Was the Mass of the Universe Immediately After the Big Bang?
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Undergrad What is the ratio of hydrogen to helium in the Sun?
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Graduate When a protostar stops contraction
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Graduate Most Distant Quasar a Theory Problem?
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Graduate Solar sail using radioactive decay
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Graduate An upper limit to the size of black holes?
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Undergrad Could a Swallowed Moon Explain Uranus's Tilt and Magnetic Field?
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Undergrad Why does the permeability of free space invoke pi?
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Graduate Mass distribution inside the event horizon
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Undergrad Relativity & Expansion of Universe: Einstein's Cosmological Constant
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Graduate An age of the Universe around 20 billion years
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Graduate Primordial Black Holes: Could Spacetime Form BHs?
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Undergrad Is the Universe Really Cyclic and Set to Repeat?
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Graduate You should be shot for asking: how does matter move faster than light?
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Graduate What Existed Before the Big Bang?
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High School Can the Earth have an asteroid stuck in permanent orbit like our moon?
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Graduate Top 10 Questions on Leonard Susskind's "The Black Hole War
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Undergrad What causes the universe to expand?
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High School Landing a Spacecraft: Understanding Gravity in Space
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Graduate Can black holes form without gravity in the early universe?
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Graduate YSBSFA: how did our matter get here ahead of the light?
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Graduate Understanding rotation of spiral galaxies
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Undergrad Space Elevators and Other Alternatives
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Graduate Control Systems, State space to Transfer Function
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Undergrad Challenges of Terraforming Mars: Temperature, Air Pressure, and Radiation
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Graduate Helium Abundance in ISM of Galaxies: Best-Estimate Value
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Graduate Cosmology Q&A: Understanding the 15.5 Billion Year Figure
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Undergrad Describe some basic concepts for me please?
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Graduate The Big Bang Makes No Philosphical Since To Me Help
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Graduate Initial conditions for a halo orbit
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Graduate Variations in the fine structure constant
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Graduate ? about Steven Weinberg's view on theroretical prejudices
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Space travel on TV infuriates me
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Graduate Does the Universe Rotate and Does it Have an Axis?
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Graduate What does homogeneity mean (in the cosmological context)?
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Graduate How Does Age, Mass, and Magnitude Mathematically Relate in Star Clusters?
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Graduate The Observable Universe: Light Travel Time and Distance
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Graduate What Causes the Increase in Area of Black Hole Horizons?
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Graduate In desperate need of some one who can help me.
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Graduate Dark Matter & Its Effects on Regular Matter
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Graduate Skyhook - is this better then space elevator?
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Undergrad How common is it for stars to have rocky bodies orbiting them?
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Undergrad Need help understanding use of cepheid variables
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Graduate Challenging the Big Bang Theory: Examining Evidence and Alternative Theories
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Undergrad New Star Squirts Water From Poles
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Undergrad Is big bang 13.7 billion years ago for all observers?
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Earth Not From Same Nebula as Sun. Huh?
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Undergrad Are blackholes formed in other ways besides supernovas?
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Graduate Could Dark Energy Alter Our Understanding of Gravity?
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Graduate Do Photons Relax? | Physics of Mass & Energy
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Undergrad How do electrons and protons interact in atoms?
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Graduate Fully relativistic, cosmological N-body simulations
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Graduate If the univese is finite will I see my light again.
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Undergrad How accurate is this short summary of physics history?
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Graduate Can Antimatter Universe Follow Physical Laws of Matter Universe?
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Graduate What is the temperature of cold & hot dark matter?
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Undergrad Calculating RA and Dec from long/lat/time/alt/azm
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Graduate Does the empty Milne Universe have a horizon problem?
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How do you pronounce perilune and apolune
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Graduate Dark matter: gamma rays, direct detection, and solar-system tests
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Graduate What Explains the Abundance of Matter During the Annihilation Phase?
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Graduate Yesterday's Nuclear Decay Related to Today's Flare
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Undergrad Viewing the beginning of the universe.
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Graduate Critical density formula hides fundamental relationship?
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Graduate Is Our Universe Really Flat or is it Just Euclidean Jargon?
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