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 Understanding Hubble's Graph: Velocity and Time Relationship Explained
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High School Why Do Hot Stars Like Zeta Puppis Appear Blue Despite Low Wavelengths?
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Undergrad Interstellar travel/centrifugal couching
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High School Why is vacuum energy assumed to be uniform?
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Undergrad Object moving out of the Observable Universe due to Expansion
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High School What is seen from the farthest star?
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High School How can the Universe grow if it is infinite?
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Undergrad Find the Age of the Universe when Matter and Radiation densities were equal
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Undergrad Exact expression for the tensor-to-scalar ratio
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High School What can we see from the farthest reaches of the universe?
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High School Generating Plausible Star Systems
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Graduate Does the Hadronic Era Alter the Equation of State?
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High School Black holes are creating galaxies with their gravitational force
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High School What would a timeline for the Big Rip look like?
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High School What is the appropriate time/matter model for the universe?
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Undergrad Can a finite universe end in heat death?
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High School How can I conceptualise light and the known universe
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Undergrad Problems with the theory of inflation
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Stargazing Trig Parallax: Measurement & Apparent Shift of Nearby Stars
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Undergrad How Does Gravity and Density Influence the Flow of Time?
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High School Infinite vs Expanding Universe: A Physics Conundrum Explained
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High School The known universe is expanding?
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Undergrad Are Galaxies Moving or is Space-Time Expanding?
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Undergrad Is there any international astronomy competitions for adults
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High School E=0. What Does That Mean for the Seasons?
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Stargazing Are there astronomy competitions?
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Undergrad Big Bang nucleosynthesis Wiki Equation for t x T^2
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Undergrad Question about expansion and photon fatigue
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Stargazing Is it a true explanation of an aberration of starlight?
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High School Is Time Expanding Along with Space in the Expanding Universe?
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High School Can a solar sail be accelerated 20% speed of light
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High School Why does expansion redshift light if....
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High School What fueled the Big Bang explosion?
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High School Is the center of the universe empty?
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Stargazing [just for fun] Planet Definition
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Undergrad How Would Future Species Understand a Dynamic Universe?
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High School Would a manned flyby of Ceres be easier than a mars landing?
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High School Could Current Technology Enable a Manned Mission to Europa?
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High School Surface Temperatures - White Dwarf vs Neutron Star
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Stargazing А neutron star and a photon sphere
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High School How long would remains be detectable?
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Undergrad Could ice exist in Lunar lava tubes?
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High School Our atmosphere and the rotating Earth
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Undergrad Why do quantum physicists claim that particles can tunnel out of a quantum well?
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Graduate Question about the age of the universe
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High School Space news and events aggregator app
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Undergrad Dark Matter Particles: College Student Seeking Theorem Evidence
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High School The distribution of normal matter precisely determines gravity
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High School Does the Frequency of Gravitational Radiation Alter the Cosmological Constant?
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High School Book recommendations for Big Bang Model?
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High School Seeing Venus with the Naked Eye - Light Pollution
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Graduate How Does Dark Matter Affect Galaxy Motion and Formation?
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High School Why do we assume the existence of time (flow)?
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Stargazing What is the best way to reduce overexposure in DSLR astrophotos?
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Undergrad What Is the Cosmic Horizon and Its Relation to Black Holes?
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Undergrad Are we living in a Boltzmann box ?
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Undergrad A possible solution to the cosmic lithium problem
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High School Top 3 brighest planets as seen from other planets
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High School Is Everything outside the local group moving away from us?
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High School Arecibo Message: Will It Be Received 25,000 Years Later?
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Graduate Detection of 6th Force of Nature: Zhang & Feng Claims
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Undergrad Variations in the local value of Hubble constant
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Undergrad How is the value of tT^2 calculated for neucleosynthesis
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Stargazing Understanding Star Formation: Triggering and Transformation Explained
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Undergrad Quasars & Redshifts: Measuring Redshifts & Jet Formation
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Undergrad What is the link between dark matter and antimatter in the universe?
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High School Geology of Ceres illuminates origin of organics
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Stargazing Can Venus be seen during the day from sea level right now?
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Undergrad Does Star's Mass Loss Challenge the Concept of Dark Energy?
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High School Finding the distance of two points from observer
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High School Challenging the Existence of Black Holes: A Critical Analysis of Recent Research
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High School Animation to explain the balance of celestial bodies of the universe
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High School How can we find the curvature of a star or planet?
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High School What part of the Moon am I looking at?
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Stargazing Expanding Universe: A New Theory on Dark Energy, Black Holes & More
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High School Perhaps a silly analogy - hologram light source retreating?
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High School Could neutrinos be the key to successful SETI communication?
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Undergrad At which time did the CMB become dark?
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Undergrad What's the Latest on Fast Radio Bursts?
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Undergrad Calculating planet's radius using a star's luminosity
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High School In how many years will the surface of the Sun be 75 degrees Fahrenheit?
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High School How can we see 45B ly away if the universe is only 13B years
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Undergrad Does the Debye Length Change with Applied Potential Strength in a Plasma?
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High School Comets, Water & the Sun: Investigating Earth's Origins
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High School White Hole as an explanation for the big bang and inflation
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Undergrad Requirements for a breathable atmosphere
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Undergrad Is there a drag on Earth caused by its motion relative to the CMB rest frame?
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High School Can a photon be made energetic enough to escape a black hole
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Undergrad Great attractor and the CMB dipole
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Undergrad Matter term in Friedmann’s equation
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Undergrad Is the Universe's Contraction Model Too Fine-Tuned to Be Plausible?
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Undergrad Why is there no "mid-Atlantic ridge" on other planets?
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High School Can Dark Matter Explain Black Holes and the Mysterious Planet-Nine?
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High School How Difficult Will It Be to Remove Mars from the Planetary Protection Treaty?
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Stargazing Exposures & Stacking for DSLR Sky Photos
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Undergrad When Does the Radiation Epoch Begin with a Scale Factor of ~t1/2?
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Undergrad Time & Cosmology: Observing Past Quantities & Effects on Equations
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High School Background Radiation: Is It From Beyond Our Galaxy?
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Graduate Question About Moving Observers and Observable Universes
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High School Why does Sirius A blink in many colors?
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