Astronomy and Astrophysics Forum

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Join in expert discussion on the topics of Astronomy and astrophysics. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Graduate Inside a black hole, looking out
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High School Book recommendation on Binary systems
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Undergrad Calculating Luminosity from Brightness: Where Did I Go Wrong?
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High School The 15 Million Degree Pinhead: The Sun's Core Materialized on Earth
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Graduate Percentage of Matter, Dark Matter and Baryonic Matter
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High School Discovering Earth's View from Epsilon Indi: Answers by Chinspinner
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High School What are the atoms floating in space
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Graduate Three Important Questions (about black holes and the Big Bang)
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Do Some Stars Possess A Particular Name?
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Graduate Oberth Maneuvers Using Sun, Jupiter & Saturn: Formulations & Assumptions
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Are there any caves on the Moon?
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Graduate Sign swapping - spacelike intervals
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Undergrad Measuring the Movement of the Stars
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Undergrad How to Identify Polar Day and Night Seasons?
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High School Direction in Space: Do We Launch Straight Up from the North and South Poles?
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High School What is Stellar Flux and How Does it Affect Solar Wind?
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Has Anyone Played Space Engineers?
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Graduate Why does surface area of an Event Horizon increase?
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Graduate Sagittarius A* and its event horizon
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Undergrad Question about Space -- Is Space itself a 4th dimensional object?
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Witnessing Geminids: Slower Meteor Shower Speed
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Graduate Entering a black hole theoretically of course
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Graduate How Does Entropy Influence Hawking Radiation in Black Holes?
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Graduate Finite Universe: Viewing All Timelines 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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Undergrad How to Calculate the Distance Between Mars and Earth?
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Capturing Stars with Mobile Devices: Fact or Fiction?
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Undergrad Did Biosphere 2 make any discoveries later used on manned spaceflight missions?
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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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High School The Fascinating Ponzo Illusion: How Our Brain Distorts the Size of the Moon
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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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Undergrad Would We See Solar Events Speed Up While Traveling to the Sun?
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Undergrad Escaping earth's atmosphere with a balloon
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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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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 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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Graduate Apparent Birghtness And Absolute Brightness
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High School Planet Trajectory: Why Elliptical & Circular Paths?
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Graduate Centrifugal Spaceship Accelerator
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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 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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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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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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Undergrad Rocky Bits in Comets: Formation from Dust?
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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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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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Undergrad Why does the sun appear to move eastwards from Earth?
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Undergrad Active Region AR2192 heading towards the limb
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Graduate Have theories been formed yet on how to stop a black hole?
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Graduate First Measurement of the Ancient Solar System's Magnetic Field
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High School Can a Camera Be Built to See Stars in Daylight?
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Graduate Is the Universe Heading Towards a Big Crunch or Eternal Expansion?
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Graduate Matter at the core of neutron star
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Undergrad Flux --> Apparent magnitude ( only 1 source )
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Graduate A Mental Conundrum -- The Big Bang & the Speed of Light
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Undergrad The mass of the sun at its beginning
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Graduate Why Does the Hubble Sphere Expand Despite the Changing Hubble Constant?
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Graduate Is Newton's third law applicable everywhere?
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Graduate Solar System Dynamics, advice for a intern.
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