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.
High School Did anyone actually see the space moving faster than light?
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High School What is the most common/likely process of the Universe?
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Undergrad The use of 3D reconstruction techniques to build a galaxy model
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Undergrad Will There Be a Solar System Navigation System for Space Travel?
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Graduate Covariance matrix size: 3x3 or 4x4?
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Undergrad Isn't planetary rock dating really supernova dating?
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High School How Do High-Speed Objects Traverse High-Temperature Gaseous Nebulas?
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High School Can black holes truly be infinite?
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Graduate CMB as thermal radiation of cosmic dust?
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Undergrad How does Hawking radiation contribute to the formation of new stars?
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Graduate Where to Find the Best Records of Past Supernova Events
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Graduate Classical scalar field as Dark Matter
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Undergrad Fine tuning and the multiverse
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Undergrad Is Bad Astronomy Using Bad Statistics?
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High School Could singularities be just rips in the space-time fabric?
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Undergrad Debunking the Moon Landing Conspiracy Theories: Evidence and Explanations
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High School Previous thoughts on destroying asteroids were wrong: Nuking them is a bad idea
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Graduate Cosmological fluctuations (Weinberg's cosmology, p. 284)
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Undergrad A very small object following Earth in the same orbit
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Undergrad Would we know if the Milky Way were a quasar?
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High School Black Holes: Observing & Understanding | Astrophysics
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High School If Quark stars exist why do Neutron stars become Black holes?
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High School What is the 'proof' of the no-hair theorem of black holes?
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Stargazing Accelerating universe - luminosity data
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Undergrad How Do We Determine the Sun's Generation?
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High School CMBR: Is It Constant or Changing Over Time?
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High School For Lack of a Better Term....Moon Motion
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Graduate Continuous Field Image: Hubble Deep Field & Exoplanets
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Undergrad Cross-correlations: what size to select for the matrix?
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High School How far back can we see with light?
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High School Questions regarding energy in the universe
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High School Question about time and its relation to spacetime
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Graduate Dark matter and the fabric of space time,
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Undergrad Is Tabby's Star Dimming Due to an Alien Megastructure?
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High School Which Hawking paper? (no singularity at the beginning of the universe)
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Graduate Is "Broken Symmetry" truly foundational?
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High School Photon Decoupling: Effects on Universe Expansion
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Graduate Decoupling of SVT Metric Perturbations
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High School Help with when expansion acceleration began
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Undergrad How is Dark Matter distributed around our galaxy?
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Undergrad Confusion about absorption spectra - cool gases absorb?
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High School Can a single photon make up a universe?
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Undergrad What is the pressure gradient towards the centre of a large planet?
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Undergrad Why ##\omega=0## for a matter dominated universe?
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Undergrad Is a "collision" of galaxies noticeable on a planetary scale
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Undergrad Expansion of positively and negatively curved universe
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Undergrad Variable Dark Energy: Would P Remain Constant?
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Undergrad Humanity: Master fusion reactors or build a dyson sphere?
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Undergrad Is Something Missing in the Expansion of Our Flat Universe?
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Undergrad Too Much Dark Matter In CEG Mrk 1216
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High School What Happens at the Event Horizon of a Black Hole?
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Undergrad How would the DSG orbit the Moon?
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Undergrad Two gravitational events might be a single lensed one
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High School Andromeda Collision VS Expansion
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Undergrad Space docking using the Meissner effect
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Undergrad Expanding universe or tired light in a static universe?
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Undergrad New Problems I have with Dark Matter
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Undergrad What Is the Singularity and Its Role in the Big Bang?
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Stargazing Stellar Eclipse on Feb 18/19, 2019
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High School Is the Rover Mission Halted Due to Dust-Covered Solar Panels?
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New Horizons flyby of Pluto [updated for Ultima Thule]
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Undergrad Difference between dark energy and dark matter
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Undergrad How Does the Sun's Position Affect the Earth-Moon Barycenter?
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High School How exactly inflation solves the Horizon Problem
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Undergrad Relative Amount of Hydrogen in the Universe
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Undergrad Galaxy at z=11.1, farthest yet, unusually bright (GN-z11)
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High School How hard is it to track moon cycles
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Undergrad Inflation resolves the horizon problem
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Undergrad Why Do Stars and Hot Metal Show Different Colors at Similar Temperatures?
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Graduate Dark matter and spacetime metric
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High School Naked Singularity, Black hole mass limit
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Undergrad Supermassive singularity the cause of the Big Bang?
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Undergrad The Universe as an isolated system
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High School The unusual motion of stars in galaxies
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Undergrad Dark energy and the rotation curve of spiral galaxies
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High School Active galaxies point to new physics of cosmic expansion
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Undergrad Does all orbiting space debris eventually fall and why?
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Undergrad Inflation and the size of the Universe
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Stargazing Potential Impact of Meteoroid During Lunar Eclipse on January 21, 2019
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Undergrad Understanding the Impact of Solar Radiation and Eccentricity on Earth's Climate
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Undergrad Why Are Star Spectra Shown as Absorption Rather Than Emission?
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Graduate Unveiling the Structure of Sagittarius A*: First VLBI Image at 86 GHz with ALMA
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Graduate Schrödinger Evolution of Self-Gravitating Disks
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Undergrad Why hasn't the Oort cloud converged to a disk shape?
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Undergrad What is the Hubble Parameter over time and how can I calculate it?
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Undergrad Luminosity Distance: Finding the Connection
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Stargazing Seeing star light -- Why does it take so long?
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High School Algebraic Topology in the tv show The Big Bang Theory
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High School Galaxy rotational curves vs time
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Undergrad Relationship between Energy density and Curvature
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Undergrad Opal Crystals on Mars: Implications for Geochemical Conditions
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Undergrad Sachs-Wolfe effect and Superclusters/Supervoids
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High School How Old is the Milky Way Galaxy?
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Graduate How do I define Open cluster membership?
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Undergrad Relativistic Reference Frames and the Big Bang?
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High School Is Dark Energy really the best term?
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Undergrad What Are the Boundaries of a Flat and Saddle-Shaped Universe?
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Graduate How Does Stellar Radiation Clear Dust from a Proto-Planetary Disc?
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High School What Mysteries Lie Between the Galaxies?
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Undergrad What are the latest thoughts about the timescape cosmology
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