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 Energy cannot be created. Then where did it all come from?
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Graduate Why Is the Universe Not Symmetrical?
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Undergrad Is the tetrahedron the building block of the universe?
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Graduate Accumulated environmental damage to Hubble main mirror
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Latest Smoothed Sunspot Number posted 8 Dec '14 at SWPC
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Undergrad Sgr. A* - Mathematical calculations
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Graduate Constants linked to the observable universe, not whole
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Undergrad How to Calculate the Distance Between Mars and Earth?
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Graduate Understanding Horizon Distance in Axion Cosmology Model
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Graduate Disappearance of dark matter since the Big Bang
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Graduate Naive Question regarding Galaxy Rotation Curves
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Capturing Stars with Mobile Devices: Fact or Fiction?
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Graduate Dark Matter and extra dimensions
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Undergrad Did Biosphere 2 make any discoveries later used on manned spaceflight missions?
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Graduate Cosmic rest frame, proper distances and comoving distances
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Reflect Cosmic Rays: Materials for Mirrors
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Undergrad Power in Sun's Core: Comparing 10^26 W to 276 W/m^3
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Undergrad Why does the Soyuz cover its main engine?
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Undergrad Why doesn't ISS pass over the polar regions?
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Graduate Understanding Hawking Radiation: Energy Subtracted from Black Holes
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Graduate Why Is Asteroid Composition Highly Varied?
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High School Why is the Solar System Flat Instead of Spherical Like Atomic Structures?
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Undergrad Uncertainty of planetary orbital period
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High School Why if we put Saturn in water, it will float?
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Graduate Find the mass of a black hole from just its radius?
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Graduate Field equations Einstein-Gauss-Bonnet action
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High School The Fascinating Ponzo Illusion: How Our Brain Distorts the Size of the Moon
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Graduate Is Inflation the Only Solution to the Homogeneity Problem in Cosmology?
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Is the Neutron Intermediary Decay W- Boson Related to Gravitational Effects?
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Undergrad How Much Declination Do Stars Need for a Luck City at Latitude 35°?
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Graduate Van Flandern's paper on "Speed of Gravity", question.
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Graduate Expanding universe and thermodynamics
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Undergrad Would We See Solar Events Speed Up While Traveling to the Sun?
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Graduate Why Are We Here Right Now Instead of Billions of Years Later?
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Undergrad What is the fate of the universe?
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Undergrad Escaping earth's atmosphere with a balloon
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Undergrad What is the correlation between the age and size of the universe?
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Graduate Smolin dispelling false impressions of the singularity
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Graduate Is the Weyl Curvature Hypothesis a Viable Alternative to Inflation?
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Undergrad Gravitational Binding Energy vs total mass energy
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High School Does the Solar System spin around an axis and if so where is it?
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Graduate Is Interstellar Travel Possible with Current Propulsion Technology?
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Best Camera for deep space object
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Graduate Is Spacetime Flat? Answers to Orbit Questions
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Graduate How can black holes have electrical charge, and spin?
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Graduate Why Stars Explode: Examining the Physics Behind Supernovas
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Graduate Observational data for evolution of Hubble rate
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Graduate Anything actually physically infinite within the universe?
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High School Understanding Acceleration and its Impact on Time and Velocity - A Question
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Undergrad Planetary Orbits & Orbital Velocity
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Graduate Could the mass of a singularity be described as an empty set
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Graduate Relativistic Degrees of freedom g(T)
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Graduate Do you know Dragan Hajdukovic's models work?
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Graduate Are there any particles with all the properties of a WIMP
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Undergrad A few very specific questions about Venus
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High School Can we decrese the timegap of space telsecope images?
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Graduate Apparent Birghtness And Absolute Brightness
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Graduate Detection of motion of non characterised particles
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Graduate Simple thought Experiment, Straight Line between 2 Distant Points
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High School Planet Trajectory: Why Elliptical & Circular Paths?
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Graduate Centrifugal Spaceship Accelerator
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Graduate Universe's Informational Content and the Big Bang
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Graduate Saha equation (experiment verification?)
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Undergrad Van Allen Belt: Why are electrons generally further out?
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Using gravity to suck matter from a star (Lexx)?
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Graduate Inflation & Its Effects on Universe's Expansion
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Graduate Variations Séculaires des Orbites PlanétairesVSDOP87
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Graduate Is there vacuum at the Event Horizon of a Black Hole?
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Undergrad Basic question about spacetime and matter
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Graduate Visual perspective at the speed of light:
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Graduate Difference between orbital mechanics and astrodynamics ?
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Graduate Various doubts about Black Holes
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Graduate Is there any evidence for MACHOs or WIMPs being Dark Matter?
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Graduate Hawking Radiation From Black Holes:
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Graduate Stealth and detection in space: Continued
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Graduate Is Superconductivity Related to the Qualities of Outer Space?
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Graduate What are the equations explaining the mass of singularities?
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Graduate The scale factor in flat FRW model
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High School About the size, brightness and distance of celestial objects
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High School Space Cold | Why No Matter Means No Heat
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Graduate How to Measure Perpendicular Peculiar Velocity in Galaxy Simulations?
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If you could meet the person who is the authority on brown and white dwarfs
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Undergrad Can a star with thousands of solar masses be formed?
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High School What is the role of gas density in determining friction in space?
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Graduate What Factors Influence the Density of a Hydrogen Cloud in Space?
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Graduate Entropy of the initital state of the universe
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Graduate Is Space-Time a Continuum or a Physical Object?
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Undergrad Rocky Bits in Comets: Formation from Dust?
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Graduate If the speed of light was greater, how would it show up?
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Graduate Spectral energy distributions of white dwarfs in 47 Tucanae
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Graduate CNO Cycle: Understanding the Last Reaction and the Mystery of 16O
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Graduate Convection vs Radiation at the giant stage of stars
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Graduate The Fastest Unbound Stars in the Universe
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Undergrad How Does Rosetta Maintain Its Position Relative to the Comet?
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High School What Are Some Cool Facts About Galaxies and Stars for a School Project?
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Undergrad Average distance among pieces of space debris in low earth orbit?
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Graduate Why is the Cosmological Redshift z Confusing?
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High School Layman question on sun as seen from mercury
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Graduate I want to spread life to space. What should I do?
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Graduate About the effects of relativity when measuring the age of the universe
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