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 Star Calculator (Excel spreadsheet)
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High School Why do heavenly bodies rotate and what causes this rotation?
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Graduate How Long Does an Interstellar Cloud Take to Contract?
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Graduate How can we accurately determine the expansion rate of the Universe?
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Graduate Can a 3-Space Be Isotropic About Two Distinct Points Without Being Homogeneous?
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High School Location of the Asteroid Belt between Mars and Jupiter
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Graduate Why Does the Expanding Universe Cause Red Shift?
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Graduate Gaining Orbital Energy from Sun's Gravity-Assist Flyby
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Graduate The maximum mass of white dwarf star
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Graduate How Many Elements Formed from Primal Plasma?
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Graduate Explanation on how inflation solves the horizon and flatness problem
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Graduate Why are the primordial fluctuations called scale invariant?
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Undergrad How to calc absolute magnitudes by comparing to the sun's luminosity
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Graduate Virtual pair production - black holes
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Graduate lowest scatter Hubble diagrams ever published (Bailey et al)
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Undergrad Question about the sun and the earth long long ago.
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Graduate Is DNA Production a Constant in the Life Cycle of the Universe?
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Graduate Do Galaxies and the CMB Share the Same Reference Frame?
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High School Gravity in the Middle of a Planet: Puzzling Questions
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Undergrad How Do Tides Reveal the Dynamics of the Earth-Moon System?
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Undergrad Dimensions vs Universes: Understanding the Distinction and Connection
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Stargazing Cleaning Eyepieces - What's the Best Method?
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Undergrad The Odds of Life in the Universe - What Are Your Thoughts?
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Graduate How is Hawking Radiation Related to a Black Hole's Mass and Time of Dissipation?
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Graduate Determining the Best Wavelength for Darwin's Space Mission
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Graduate What is the force of the cosmological constant?
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Graduate How display a mollview projection of CAMB output fits file ?
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Undergrad Could the shuttle land with Hubble?
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High School Is Mars Really Approaching Close to Earth on August 27th?
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Undergrad Can elevons and rudders effectively steer spacecraft in the vacuum of space?
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Graduate Can we determine the rotation speed of a black hole?
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Graduate How are Supernovae Ia and Dark Energy Related?
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Graduate Formation of Relativistic Jets from Black Holes
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Graduate How Does Hawking's 4D Closed Manifold Theory Align with an Expanding Universe?
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High School What makes an asteroid an asteroid and not a comet
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Graduate Best model to explain expansion of universe is needed
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Graduate Assigning Contributions of Dark Energy to the Cosmos
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Undergrad What are the actual dimensions of the Horsehead nebula?
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Graduate What is Equation of state for the Dark Matter?
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Graduate The new Hubble rate estimate of 74 means a new critical density.
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Graduate Attraction Forces During Total Eclipse: Sun, Moon, and Earth Explained
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High School Is the Spin of Earth Constant Throughout the Year?
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Graduate How can it be that gravity can bend time and slow it down
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Graduate What are the differences between rotating and non-rotating black holes?
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Undergrad Speed of Light: Distant Galaxies & Observability
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Graduate Is it Possible to Escape a Black Hole Using a Spaceship and Hawking Radiation?
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Graduate Is Our Universe the Creation of Intelligent Aliens?
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Graduate How does the equation-of-state depend on the Quintessence potential?
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Graduate Is gravity driving the expansion of the universe? If so
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Graduate Is Cosmic Radiation Accounting for Missing Matter and Energy in the Universe?
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Graduate Schwartzchild Radius & entropy
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Undergrad Is there really a black hole at the center of the Milky Way?
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Undergrad Works of Riemann related to Astronomy that I can understand?
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Undergrad Does Star Evolution Always Lead to Expansion?
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Graduate What Does John A. Wheeler's 'Participatory Principle' Mean for Modern Cosmology?
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Graduate Unraveling the Mystery of Dark Matter: Analysis of Recent Science Media Coverage
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Graduate Moving an asteroid into Earth orbit
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Graduate Dark flow: Proof of another universe?
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Graduate Necessary Conditions for The Big Bang: A Scientific Exploration
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High School Giant mystery blob found near dawn of time
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PG&E makes deal for space solar power
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Graduate What Is Containing Our Universe?
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Undergrad Why are the orbits elliptical in shape?
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Undergrad How much lighter do I weigh at noon than I do at dawn?
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Graduate Gravity vs O-Force: Uncovering the Mysteries of Cosmology
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Graduate What Was the Force Holding Matter Together Before the Big Bang?
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Graduate If objects are accelerating, are we measuring the systems getting smaller?
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High School Calculating Earth's # of Rotations Around the Sun
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Graduate Accelerating universe, decreasing hubble constant
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Graduate Can We Bend Space-Time? Discover the Latest Experiment Findings
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Undergrad Peculiar vs. Irregular galaxies? Difference?
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Undergrad How to Calculate Distances and Luminosities of Stars?
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Graduate Nothingness and the rise of something
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Undergrad Was that end of theoretical physics?
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Graduate How are the percentage contents of the universe calculated?
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Graduate Why black holes do not have color charge?
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Graduate Do any singularities have Infinite density
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Undergrad Expanding Light: Wave's Radius Increase - Why Not Dim?
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Graduate The Hubble Constant and the Expansion of the Universe
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Graduate How Far Can We Explore Beyond the Mysterious Space Blob 'Himiko'?
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Graduate Galaxy Questions: Types, Shapes, Evolution & Masses
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Graduate What Is the Observable Universe's Center and Expansion?
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High School Why Is the Earth Slowing Down?
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Graduate Is Space Really Falling Faster Than Light Near a Black Hole?
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High School Photos of the our milky way galaxy
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Graduate Is the Age of the Universe Relative and What is the CMB Speed Measured Against?
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Graduate What Drives the Expansion of the Universe?
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High School Spin of planets, bigger means faster?
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Graduate Does time exist for cosmologists?
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Graduate When is a Principle not a Principle?
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High School Discovering the Mystery of Satellite Shadows: A Beginner's Guide
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Graduate CMB Anisotropy: Measuring Our Motion Through Space
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Graduate What Does 'Quake Confinement' Mean in Astrophysics?
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Graduate Wormholes and time travel - Problem
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Graduate What is Causing The Universal Expansion?
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High School How do astronauts communicate with Earth during space missions?
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Galaxy's centre tastes of raspberries and smells of rum
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Graduate CMB Redshift Question (Visible Wavelengths)
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Graduate The Mystery of Expanding Space: Uncovering the Truth Behind Dark Energy
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Undergrad How to Calculate Inclination Angle for Galaxies in the Tully-Fischer Relation
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