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 Why can we see the CMB in every direction we look?
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Undergrad How Is the Angular Diameter of Jupiter Measured and What Equipment Is Used?
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Graduate Cosmic inflation and singularity
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High School Radiation on Mars: Does it Lack a Magnetosphere?
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Undergrad Why does gravity increase when a star dies?
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Graduate Questions about the multiverse theory
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Graduate Can we ask such a question about expansion of universe?
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High School How Often Do Blue Moons Really Occur?
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Graduate Our attempts at certainty (measurements) actually increase uncertainty
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Earth-sized exoplanet spotted in star’s habitable zone
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Undergrad Collision Sparks Star Birth at Our Galaxy's Edge
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Graduate Can Pulsar Timing Arrays Detect Gravitational Wave Bursts with Memory?
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Undergrad Is it really possible to see down to mag 8?
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Graduate Sterile Neutrino Dark Matter: Case Advanced
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Graduate Information on large scale structure?
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Undergrad Can NMEA (GPS) Data Tracker Help Improve Signal Reception?
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Are green <5mW laser pointers legal to use in New York City?
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Graduate Why do we observe only microwaves in the background radiation?
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Graduate Angular momentum of galaxies in galactic clusters
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High School Which Variable Star Has the Longest Period?
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Graduate Bullet Cluster: Controversial & Puzzling Evidence for Alternative Models
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Graduate When we look at cosmic web images, what do we see?
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High School Can WorldWide Telescope Help View Gas Clouds, Star Systems, and Galaxies Online?
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Undergrad Time travel into the past a possibility now?
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M42 and the Running Man nebula with Takahashi 150mm
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Graduate Matter production during inflation
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Graduate Is 4th Quantisation the Key to Understanding Multiverse Interactions?
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Graduate BransDicke Cosmology and Accelerated Exlansion
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Graduate What Gets 2nd Quantised in the WDW Equation: Geometry, Matter, or Gravity?
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Undergrad Light & Black Hole: Absorbing Light w/o Mass
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Graduate SVT Decomposition: Definition and Purpose
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Graduate Formation of 1st Solar System: Timeline Since Big Bang
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Graduate Superluminal Gravitational Acceleration
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Undergrad Iapetus equatorial ridge fell from the skies
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High School Doubt in a scene from the movie Gravity
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Graduate Quick question on CMB anisotropy in Earth frame
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Undergrad Is circumnavigation possible on Phobos or Deimos?
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Undergrad The Sun's Next Phase: Can We Avoid Extinction?
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Graduate Eternal inflation disfavored by Planck and BICEP2?
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Undergrad Why terrestrial planets in inner solar system & gas giants in outer?
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Graduate Found: The First Double Star That BRIGHTENS During Eclipse
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Graduate Age of the Universe: Intuitive Understanding
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Graduate Is the Big Bang Caused by a Four-Dimensional Explosion?
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Undergrad Why is angular momentum not conserved in 2 similar mass planet system?
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Undergrad How accurate is our image (depiction) of the Milky Way?
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Graduate Understanding the Luminosity of Radiative Stars
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Stargazing How big would a neutrino telescope have to be?
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Blood moon Total Eclipse tonight
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Graduate Big Rip Cosmology and Many-Worlds Quantum Mechanics
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Undergrad Why did Earth lose its first atmosphere but keep its second?
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High School How did Copernicus get the idea of the heliocentric model?
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Graduate Is the universe a causal system?
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Graduate Reconsidering the Speed of Light: A Crazy Idea on Dark Matter and the Big Bang
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Graduate What would happen if the moon's orbital radius were increased?
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Graduate How Does Space-Time Function at the Big Bang?
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Graduate Neil deGrasse Tyson's Observable Universe
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Graduate Ideal gas laws in cosmology usage
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I captured a celestial event, could someone explain what it is?
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Graduate Why Are Saturn's Rings and Planetary Orbits Aligned Despite Cosmic Disturbances?
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Undergrad What are the mysterious properties of Dark Matter?
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Graduate What does it mean when cosmologists say the universe is flat?
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High School Although the wrong theories contributed to scientific evolution
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High School Gravitational Constant: Earth vs Other Planets
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The Mystery of the Pre-Big Bang Universe
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Undergrad How do they calculate how fast celestial objects are moving?
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Graduate Was matter created during the big bang?
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Graduate What is the problem with the Big Bang Theory and seeing the early universe?
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High School Why is the universe considered as cold?
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Graduate Cosmological Redshift: Electron Energy Loss in Expanding Universe?
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High School Which Telescope Offers the Best Value for Under $150?
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Undergrad Unusual light rising from Martian surface
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Graduate Could the collapse of a black hole lead to the creation of a new Big Bang?
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Graduate Does BICEP2 kill Conformal Cyclic Cosmology?
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Graduate What Are the Dynamics and Time Scales of Dark Matter Halos?
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Graduate How can we predict a Big Crunch?
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Graduate Why do stars show absorption lines?
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Undergrad Gravitational Redshift and Hubble.
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Graduate Describe & explain the significance of the 3K CMB
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Undergrad Is the Mass-Luminosity Relationship for Main-Sequence Stars Linear?
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Graduate Black Hole Formation and Iron Distribution
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Graduate What sets the fusion rate in a main-sequence star?
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Graduate Calculating critical density of mass, from Hubble time, for exercise
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Graduate Does Dark Matter Surround Us Unseen?
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Undergrad The Sun's End: Predicting the Inevitable
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Graduate How many particles could be crammed into the universe?
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Graduate Quantum perspectives in basic astrophysics?
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Time magazine spreads the horse manure
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Graduate Understanding Photon Thermalization and Its Impact on CMB Anisotropies
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Graduate Orbit change due to hypothetical mass change
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Undergrad Help building an n-body simulation incorporating the speed of gravity
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Graduate Are Modifications Needed for Escape Velocity in Elliptical Orbits?
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Graduate How to Plot a Map Using Healpix and Real Data?
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Undergrad Expansion of space vs stuff just moving away
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Graduate Help understanding the Friedmann equations?
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Undergrad Smallest Body Possible to Have Rings
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Graduate Press Conference on Major Discovery - primordial B modes?
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Graduate Near black hole event horizon time dilation?
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Undergrad Where Do Stars Form: Cool Nebulas or Hot Nebulas?
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Graduate How does a solar flare cause a magnetic crochet?
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High School Can Sun's Gravity Alter Earth's Landscape Over Billions of Years?
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