Astronomy, Astrophysics, Cosmology Forum

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.

Threads

Undergrad The Pleiades Controversy Erupts Again

  • CygnusX-1
  • · Replies 1 ·
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1

Undergrad Low-eccentricity orbits and the Plane of the Elliptic

  • GofG
  • · Replies 2 ·
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2

Graduate Chandler wobble: nutation or precession?

  • stroustroup
  • · Replies 2 ·
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2

Graduate Mass radius relationship for SIRIUS B

  • cooper607
  • · Replies 5 ·
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5

Graduate Constraints on gravity and dark energy

  • Chronos
  • · Replies 1 ·
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1

Graduate Gravity Waves and Graceful Exit

  • enorbet
  • · Replies 5 ·
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5

Undergrad Resources for star evolution data and chemical composition

  • nick1o2
  • · Replies 4 ·
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4

High School Measuring the current Longitude and Latitude of your current position

  • Philosophaie
  • · Replies 1 ·
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1

Graduate Universe Expansion: Is Merging Possible?

  • starligh98
  • · Replies 5 ·
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5

Graduate Misalignment of angular momentum of stars (simulation)

  • shadi612
  • · Replies 1 ·
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1

Graduate Could quantum foam at Planck scales create a universe-destroying bubble?

  • djamie
  • · Replies 9 ·
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9

Graduate What happens to the gravitational energy of a cooling brown dwarf galaxy?

  • wolram
  • · Replies 4 ·
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4

Graduate Do photons' gravitational effects account for dark matter and dark energy?

  • backenvelope
  • · Replies 2 ·
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2

Graduate How are solar particle events predicted? And related to flares/CMEs?

  • martiandawn
  • · Replies 3 ·
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3

Graduate Does the zero-energy universe account for electrical potential energy?

  • DiracPool
  • · Replies 3 ·
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3

Undergrad Map or a Listing of All the Constellation Boundaries in Right Ascensio

  • Philosophaie
  • · Replies 2 ·
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2

Graduate How many dimensions are there to space time?

  • Cyber Space
  • · Replies 10 ·
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10

Undergrad Expanding universe, big bang question

  • deadcat
  • · Replies 7 ·
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7

Graduate Why does a photon lose energy to cosmic redshift without interacting with anything?

  • vinven7
  • · Replies 14 ·
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14

Graduate Is 16.4 GHz a Significant Frequency in Radio Astronomy?

  • neilparker62
  • · Replies 8 ·
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8

Undergrad Calculate Area of Ellipse in Keplerian Orbit

  • cptolemy
  • · Replies 4 ·
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4

Graduate Do age and size calculations for the universe use different parameters?

  • Jozsef
  • · Replies 19 ·
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19

Graduate Expansion by doppler (red) shift

  • Mike x10-35
  • · Replies 11 ·
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11

Graduate How close would a Type Ia supernova need to be to cause extinction via gamma ray burst?

  • TimeHorse
  • · Replies 6 ·
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6

Graduate Does Gravitational Time Dilation Impact Cosmological Age Estimates?

  • pforeman
  • · Replies 15 ·
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15

Graduate What Are the Community's Theories on Dark Matter?

  • deadcat
  • · Replies 6 ·
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6

High School Can Astronomers Predict when a star will explode?

  • !Jon Snow!
  • · Replies 4 ·
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4

Graduate The big crunch effect on entropy and time

  • blakej
  • · Replies 1 ·
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1

Graduate Why does dark energy exist if early expansion was naturally faster?

  • exDark
  • · Replies 9 ·
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9

High School Is it true that if two pieces of metal touch in space

  • !Jon Snow!
  • · Replies 3 ·
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3

Graduate Can Dark Matter Radiate Heat or Form Black Holes?

  • !Jon Snow!
  • · Replies 7 ·
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7

Graduate Dark Matter. Space-Time curvature. Galaxy formation

  • Joshuacan
  • · Replies 22 ·
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22

Undergrad Is a black hole black from all directions?

  • !Jon Snow!
  • · Replies 5 ·
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5

Graduate Can the universe be both infinite AND expanding

  • Silvers931
  • · Replies 2 ·
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2

Undergrad Why do all the planets orbit in the same plane?

  • QEDrpf33
  • · Replies 25 ·
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25

Graduate As I Was Looking At A Strange Black Hole Image I Wondered

  • Kenton
  • · Replies 8 ·
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8

Undergrad Can Gas Giants' Atmospheres Ignite Without Oxygen?

  • SatSat
  • · Replies 2 ·
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2

High School Would Earth leave its orbit immediately if the sun disappeared?

  • ketanco
  • · Replies 8 ·
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8

Undergrad Geocenteric Equatorial Coordinates of the Sun

  • cp11
  • · Replies 1 ·
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1

High School How bright was the Chelyabinsk meteor strike?

  • TumblingDice
  • · Replies 6 ·
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6

Graduate True map of universe from computer simulation with CMB initial state

  • divitWasHere
  • · Replies 4 ·
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4

Undergrad Do we live in a black hole(or an white hole)

  • dxkiller
  • · Replies 6 ·
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6

High School Can a planet have different levels of gravitational pull

  • !Jon Snow!
  • · Replies 8 ·
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8

Graduate Is there radiation colder than the CMBR?

  • Lino
  • · Replies 31 ·
2
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31

Graduate Making new sense of the three-body problem

  • victorvmotti
  • · Replies 1 ·
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Graduate Second moment of mass and energy for a torus using E=mc²

  • colinbeaton1
  • · Replies 1 ·
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1

Graduate Who Determined the Phase and Period of Epicycles in Greek Astronomy?

  • puncheex
  • · Replies 3 ·
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3

Graduate Are There Documented Polarities in Comets' Magnetic Fields?

  • bitznbitez
  • · Replies 1 ·
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1

Graduate Rational ratio of frequencies leads to isolating integral of motion

  • victorvmotti
  • · Replies 2 ·
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2

Undergrad How do we know the orbits of the planets?

  • Droctagonopus
  • · Replies 9 ·
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9

Graduate Why is the CMB Visible if Younger Light Sources Are Not Yet Visible?

  • connorp
  • · Replies 18 ·
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18

Undergrad Creating an equation of a 2D path of an orbit

  • beamthegreat
  • · Replies 6 ·
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6

Undergrad The Most Distant Star in the Milky Way

  • CygnusX-1
  • · Replies 7 ·
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7

Undergrad Calculating perfect full moon observation locations and dates

  • anorlunda
  • · Replies 4 ·
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4

Graduate Our universe may have emerged from a black hole in a higher-dimensiona

  • Tanelorn
  • · Replies 7 ·
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7

Graduate Conservation of mass and black holes

  • soulmartyr
  • · Replies 8 ·
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8

Graduate Energy of an Expanding Universe Decreases?

  • yogi
  • · Replies 19 ·
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19

Graduate Dark matter = ligh energy, Dark Energy = also light energy?

  • arnesinnema
  • · Replies 16 ·
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16

Undergrad Can humans reach near-light speed in a lifetime with 5G acceleration limits?

  • Keith
  • · Replies 1 ·
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1

Graduate Unidentified emission line in Galaxy Clusters

  • DennisN
  • · Replies 4 ·
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4

Graduate Direct detection of dark matter?

  • Chronos
  • · Replies 9 ·
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9

Graduate Could the big bang have been a white hole?

  • AstronomyX
  • · Replies 4 ·
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4

Undergrad What is Specific Intensity in Astrophysics?

  • shanepitts
  • · Replies 12 ·
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12

Stargazing Cleaning corrosion from a 300mm telescope mirror

  • BOAS
  • · Replies 4 ·
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4

Stargazing What equations do I need to design a truss tube dobsonian telescope?

  • Tyrion101
  • · Replies 12 ·
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12

Graduate Calculating planetary aspects beyond conjunction with Jean Meeus library

  • orbit123
  • · Replies 3 ·
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3

Graduate Minkowski Space: Can Objects Have Same World Line?

  • VaibhavP
  • · Replies 1 ·
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1

Graduate Does matter reach light speed crossing a black hole's event horizon?

  • spacecadet11
  • · Replies 3 ·
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3

Graduate Calculate Interstellar Rock Orbit in Solar System

  • Rohith8193
  • · Replies 9 ·
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9

Graduate Origin of Dimensions: Evidence of Order or Big Bang Simultaneity?

  • DiracPool
  • · Replies 2 ·
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2

Graduate Solar Gravity: Is There Good Data?

  • jkg0
  • · Replies 4 ·
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4

Graduate Question regarding the universes origin

  • Silvers931
  • · Replies 11 ·
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11

Undergrad Why does'nt SUN burst like a baloon and collapse?

  • gianeshwar
  • · Replies 5 ·
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5

Graduate Infinite universe but finite beginning?

  • MathiasArendru
  • · Replies 37 ·
2
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37

Graduate Gravitational effect of virtual particles

  • trendal
  • · Replies 9 ·
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9

High School Scale of the universe if a star was a grain of sand

  • pelooyen
  • · Replies 5 ·
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5

Graduate Can black hole entropy be observer-dependent?

  • enquirealways
  • · Replies 30 ·
2
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30

Graduate How many gravitons are there in the observable universe?

  • jimgraber
  • · Replies 7 ·
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7

Graduate Variational Principle for Spatially Homogeneous Cosmologies/KK-theory

  • center o bass
  • · Replies 2 ·
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2

Undergrad Does Aluminum Coating on Telescope Mirrors Turn into Aluminum Oxide?

  • anorlunda
  • · Replies 3 ·
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3

Graduate What happens to the energy when the universe dies out?

  • louisbaron
  • · Replies 3 ·
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3

Undergrad Calculating latitude and longitude at any time

  • z.js
  • · Replies 11 ·
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11

Did Humans Go to the Moon? A Debate

  • Hepic
  • · Replies 2 ·
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2

Graduate Could Space Topologies Unify Matter and Energy in a Curved Cylinder Model?

  • scientistshaad
  • · Replies 4 ·
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4

Graduate What is Kepler-70b's surface like?

  • Pds3.14
  • · Replies 3 ·
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3

Undergrad Could our solar system exist 100x bigger?

  • louisbaron
  • · Replies 4 ·
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4

Graduate Could tardigrades survive in Titan's hydrocarbon seas?

  • Ontophile
  • · Replies 3 ·
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3

Graduate Does cosmic inflation affect the time dimension if it only expands space?

  • Mayank_Jha
  • · Replies 23 ·
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23

Graduate Would artificial gravity work on a long-duration Mars mission?

  • Paul Wilson
  • · Replies 36 ·
2
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36

Undergrad Any dates/venues of lectures in the UK?

  • goldsax
  • · Replies 2 ·
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2

Graduate Black Holes in the center of galaxies

  • marmstrong941
  • · Replies 11 ·
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11

Undergrad What are some recommended books on white dwarf stars?

  • clumps tim
  • · Replies 3 ·
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3

Graduate Atmospheric Transmittance Venus?

  • Nostalgia00
  • · Replies 2 ·
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2

Graduate How do they define luminosity function in astrophysics?

  • clumps tim
  • · Replies 2 ·
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2

Graduate What is the Lorentz transformation

  • Greg Bernhardt
  • · Replies 1 ·
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1

Graduate All About the Einstein Field Equations

  • Greg Bernhardt
  • · Replies 1 ·
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1

Graduate What is the Mass–energy equivalence

  • Greg Bernhardt
  • · Replies 1 ·
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1

High School What are Trojan Asteroids and How are They Named?

  • Greg Bernhardt
  • · Replies 1 ·
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1

Undergrad Synodic Period: Definition & Equation

  • Greg Bernhardt
  • · Replies 1 ·
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1

Undergrad What is a sidereal period?

  • Greg Bernhardt
  • · Replies 1 ·
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1