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

Stargazing How do you make polar alignment easier for stargazing photography?

  • Space_Girl
  • · Replies 7 ·
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7

Undergrad How bright will Musk's Tesla car be in the sky?

  • swampwiz
  • · Replies 14 ·
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14

High School Maximum weight of a Neutron star

  • wolram
  • · Replies 5 ·
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5

Graduate Galaxy mass distribution without DM

  • Jeon
  • · Replies 9 ·
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9

Graduate Virial thereom as applied to clusters of galaxies

  • alantheastronomer
  • · Replies 2 ·
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2

Graduate Planck 2015 CMB temperature individual pixel variance

  • tjsotherone
  • · Replies 6 ·
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6

Undergrad What it takes to start a space exploration company?

  • Prof Sabi
  • · Replies 2 ·
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2

Stargazing Solar eclipse on February 15, 2018

  • Space_Girl
  • · Replies 6 ·
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6

High School Why did our universe come from nothing instead of something else?

  • RajeshR
  • · Replies 41 ·
2
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41

Undergrad Continuous Lensing Models: Discrete Data

  • BOAS
  • · Replies 1 ·
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1

Undergrad Changing the ISS's orbital inclination to match the Moon

  • Alec Dacyczyn
  • · Replies 4 ·
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4

Undergrad Which lunar pole is better for mining, moonbase, and solar power?

  • Al_
  • · Replies 33 ·
2
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33

Undergrad What is the New White Dwarf Mass Limit?

  • |Glitch|
  • · Replies 9 ·
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9

High School Could we launch spaceships from a long horizontal ramp?

  • Martin Peasha
  • · Replies 2 ·
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2

High School Why are aurora always in the vicinity of Earth's poles?

  • al33
  • · Replies 2 ·
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2

High School Adding a huge electric charge to a black hole?

  • Go Nucelar
  • · Replies 42 ·
2
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42

High School Is cosmopsychism theory just babble copied from The Force?

  • swampwiz
  • · Replies 1 ·
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1

High School Scattering of light in a strange fashion

  • Afina
  • · Replies 2 ·
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2

Undergrad Mass in the early universe and the CCC model

  • windy miller
  • · Replies 15 ·
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15

Undergrad How are protostars detected in images?

  • nmsurobert
  • · Replies 6 ·
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6

High School Light spectrum of planet Earth as seen from space

  • William LL
  • · Replies 3 ·
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3

Undergrad Extragalactic Planets Observed Using Microlensing

  • jim mcnamara
  • · Replies 3 ·
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3

High School The Universe vs Observable Universe

  • Tangent87
  • · Replies 29 ·
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29

Undergrad Orbit simulations, tidal forces and planetary oblateness

  • madsmh
  • · Replies 10 ·
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10

Undergrad What Are the Best Academic Journals for Aspiring Planetary Scientists?

  • astrogato96
  • · Replies 5 ·
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5

High School Is blue shift as common as red shift?

  • BL4CKB0X97
  • · Replies 26 ·
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26

High School If the moon were a light bulb how many watts would it be.

  • zdcyclops
  • · Replies 13 ·
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13

High School The Moon's inclination to Earth's equator

  • jordankonisky
  • · Replies 3 ·
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3

High School Tonight's full moon and lunar eclipse

  • Charles Link
  • · Replies 11 ·
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11

High School How Can Astronomy Even Occur? (Oort Cloud)

  • Carpe Physicum
  • · Replies 35 ·
2
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35

Graduate Can a 3d holographic universe exist in 3d?

  • Suekdccia
  • · Replies 1 ·
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1

High School MPEG movie: traveling to a black hole or a neutron star

  • Arman777
  • · Replies 1 ·
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1

High School Can Star Wars-like asteroid storms exist?

  • GTOM
  • · Replies 1 ·
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1

High School What would temperatures look like from the singularity of a 25 solar mass black hole?

  • DiscoProJoe
  • · Replies 13 ·
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13

High School Why does color temperature differ from effective temperature for different star types?

  • heavystray
  • · Replies 2 ·
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2

Undergrad Question regarding Evaporation of galaxies

  • Buzz Bloom
  • · Replies 4 ·
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4

Undergrad Star Gravitational Binding Energy Questions

  • Assaltwaffle
  • · Replies 8 ·
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8

High School Why Do We Use Different Pairs of Filters to Determine the Temperature of Stars?

  • heavystray
  • · Replies 5 ·
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5

High School Are black holes infinitely dense?

  • Aliam1
  • · Replies 6 ·
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6

High School Temperature based on colour index using Planck's law

  • heavystray
  • · Replies 4 ·
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4

Undergrad Is it possible to stretch a singularity?

  • Darkmisc
  • · Replies 6 ·
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6

High School Is the starshade going to be positioned in a fixed location?

  • roineust
  • · Replies 7 ·
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7

Undergrad Type Ia supernova involving binary white dwarfs?

  • bbbl67
  • · Replies 8 ·
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8

Graduate Could Dark Matter be H or He? They are pervasive

  • David Roberts
  • · Replies 11 ·
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11

Graduate Why don't primordial black holes couple to the baryon-photon fluid in the radiative era?

  • fhenryco
  • · Replies 10 ·
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10

High School Unusual object on video - any explanation?

  • MulderFBI
  • · Replies 3 ·
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3

Graduate Are our equations for this universe valid in all universes?

  • cosmicalset
  • · Replies 5 ·
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5

Undergrad Some confusion about Kepler’s formula

  • JohnnyGui
  • · Replies 11 ·
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11

Undergrad Deriving the Cosmological Constant

  • Arman777
  • · Replies 13 ·
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13

High School Wonder-inducing ring galaxy image

  • jim mcnamara
  • · Replies 5 ·
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5

High School Time dilation at near-light speeds for a trip to Andromeda

  • The Grassy Knoll
  • · Replies 7 ·
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7

High School Is additional maths essential for astronomy?

  • ZiHao
  • · Replies 2 ·
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2

High School Why is there something rather than nothing?

  • alan123hk
  • · Replies 2 ·
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2

Undergrad I use an Olll filter to view emission nebula -- how do they work?

  • jordankonisky
  • · Replies 1 ·
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1

Undergrad Topology of the Universe and infinities

  • Arman777
  • · Replies 13 ·
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13

Undergrad Could it have been the Big Leak and not the Big Bang?

  • Robert P
  • · Replies 26 ·
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26

Undergrad Moon vs Earth for launch to Mars

  • Rednecknav
  • · Replies 98 ·
4
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98

Should We Develop a Unique Terminology for Alien Lifeforms?

  • r8chard
  • · Replies 31 ·
2
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31

High School Gravastar vs. Neutron Stars: A New Theory for Black Hole Formation?

  • darkmattermonkey
  • · Replies 4 ·
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4

Graduate Zenith and nadir orientation on the celestial sphere

  • starstruck_
  • · Replies 7 ·
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7

Undergrad Why do very hot and cool stars show weak hydrogen lines?

  • nmsurobert
  • · Replies 9 ·
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9

Undergrad If the universe is infinite in size, did the Big Bang still happen?

  • abbott287
  • · Replies 73 ·
3
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73

Graduate How can the universe keep on expanding if it's infinite?

  • Aarav Sangar
  • · Replies 4 ·
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4

Stargazing INTEY 70mm telescope for beginners

  • Hawksteinman
  • · Replies 10 ·
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10

Undergrad How do CTCs allow a universe to self-create?

  • relatively-uncertain
  • · Replies 3 ·
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3

High School What is the highest redshift (Z number) a galaxy can have?

  • wolram
  • · Replies 5 ·
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5

Insights A Journey Into the Cosmos - FLRW Metric and The Friedmann Equation - Comments

  • Arman777
  • · Replies 0 ·
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0

Undergrad Were all these exoplanets a surprise?

  • sophiecentaur
  • · Replies 6 ·
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6

Graduate Could vacuum decay fundamentally change our universe?

  • Suekdccia
  • · Replies 5 ·
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5

High School Could Oumuamua be an alien spacecraft?

  • lifeonmercury
  • · Replies 25 ·
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25

High School How did Jupiter and Saturn disrupt our solar system

  • wolram
  • · Replies 6 ·
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6

High School Can we identify the centre of the Universe?

  • jefsART
  • · Replies 97 ·
4
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97

Undergrad Can anyone tell me if 2009 MS9 is prograde or retrograde?

  • Edward Barrow
  • · Replies 3 ·
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3

Undergrad Origin of supermassive blackholes in the very early universe

  • tuantle
  • · Replies 12 ·
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12

Undergrad Are Stars Absorbing and Re-Emitting Radiation from Space?

  • nmsurobert
  • · Replies 1 ·
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1

Undergrad Why wasn't Oumuamua detected before October 2017?

  • roineust
  • · Replies 86 ·
3
Replies
86

Undergrad Is Tabby's Star a Binary System or an Alien Megastructure?

  • fizzy
  • · Replies 22 ·
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22

High School Cassini's topographic map of Titan reveals liquid flows

  • wolram
  • · Replies 7 ·
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7

Graduate Does the event horizon coincide with a black hole's physical surface?

  • Philippos
  • · Replies 15 ·
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15

Insights Coordinate Dependent Statements in an Expanding Universe - Comments

  • Orodruin
  • · Replies 2 ·
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2

High School How thick is the Milky Way disk?

  • Suyash Singh
  • · Replies 1 ·
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1

Undergrad Update on liquid water on Mars - maybe it is sand?

  • mfb
  • · Replies 12 ·
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12

High School What was matter like during the GUT and Electroweak Epochs?

  • Comradez
  • · Replies 17 ·
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17

Undergrad Why do different cosmological models fit the same experimental data?

  • marie
  • · Replies 3 ·
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3

High School History of RA [why is the vernal equinox used?]

  • nearc
  • · Replies 5 ·
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5

Undergrad Does space expansion weaken gravity and the strong force?

  • Paul Howard A
  • · Replies 24 ·
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24

Undergrad How do we distinguish cosmological redshift from Doppler redshift in observations?

  • exmarine
  • · Replies 24 ·
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24

Stargazing The League of Extraordinarily BIG Telescopes

  • OmCheeto
  • · Replies 8 ·
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8

High School Is a Black Hole Really Waterproof?

  • Ozfer
  • · Replies 2 ·
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2

Graduate The unsolved engineering of the "Space Ladder"

  • Lorzazu
  • · Replies 25 ·
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25

Undergrad How Does Einstein's Curvature of Space Affect Celestial Orbits?

  • nnkl
  • · Replies 2 ·
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2

High School From where is the universe expanding?

  • Odette
  • · Replies 5 ·
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5

Undergrad What Values Can Ωk Take in the Equation Ωm+Ωr+Ωk=1?

  • Arman777
  • · Replies 5 ·
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5

Undergrad Calculating signal to noise ratio for deimos data

  • Curtnos
  • · Replies 3 ·
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3

Undergrad JPL Ephemeris Files: Calculating Heliocentric Pos. of Mars

  • cptolemy
  • · Replies 1 ·
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1

Stargazing Astounding Moon Astro Photos: Capturing the Beauty of Our Celestial Neighbor

  • davenn
  • · Replies 5 ·
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5

Undergrad Energy needed to move space debris to L2 or L4/L5

  • Rednecknav
  • · Replies 15 ·
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15

Undergrad Observable Universe Tempature and CMB

  • Arman777
  • · Replies 11 ·
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11

Undergrad What Does Redshift and Scale Factor Tell Us About the Size of the Universe?

  • Arman777
  • · Replies 8 ·
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8

Undergrad What's the effect of solar pole reversal on the Parker Spiral?

  • Sanborn Chase
  • · Replies 3 ·
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3