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1500 questions
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What on-site equipment is installed with radio telescopes?
I hope this question isn't too broad.
I'd like to know something about radio telescopes, precisely what equipment they have.
When I search "radio telescope control room" in image search engine, I see a lot of electronic devices; I imagine they are…
john_smith
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As of now how much larger is our practically observable universe compared to just prior to JWST becoming operational
On April 2 2022 I asked for estimates of expected results. How much larger will the "observable by us" universe be when JWST becomes operational?.
As of Jan 27 2024 with JWST operational for about 18 months how much larger (percent) is the…
BradV
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Was this video shot with a ground based hobby astronomer telescope?
I stumbled across this video capturing the rings of Saturn and wanted an expert opinion.
This video of Saturn looks so good that I was wondering if it was really shot by a hobby astronomer's telescope or if it came from the James Webb or some other…
Substantialist_Jules
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If the universe has no true center, could it have antipodes?
Some time ago, I wondered where the center of the universe could be, and the answers I found were pretty much in agreement that there was no center of the universe, as paradoxical as that might seem.
So I started wondering, just as the surface of…
J-L
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13
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1 answer
What star is this?
From this image, can you help me identify the star circled in yellow? This picture was taken mostly above my head, but facing slightly southeast, from the southwestern corner of Virginia.
rclev
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13
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Are there mascons on Ganymede similar to the ones on the Moon? And if so, how will that impact JUICE when it orbits over Ganymede?
Mascons, also known as mass concentrations, are anomalous features on the Moon that tug on orbiting spacecraft and cause their orbits to decay and crash on short timescales. There are only a handful of known orbits with select inclinations and other…
user267545
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How do Spiral Galaxies become flat?
Our galaxy has been described as roughly the shape of a pizza and the Andromeda galaxy, though I've never heard it described that way, appears similarly disk shaped. Spiral galaxies make up (roughly) about 60% of the observed galaxies in the…
userLTK
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6 answers
How to describe the Sun's location to an alien from our Galaxy?
Let's say you got to the planet orbiting other star in our Galaxy through the wormhole. You think that the travel was instant but you're not 100% sure and it is not exactly known. The planet is inhabited by aliens who agree to send you back but they…
J. A.
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Did the Late Heavy Bombardment Period Happen Because of a Stellar System Collision?
I was thinking about the impending collision between M31 and the milky way galaxy, and I've heard that since a galaxy is mostly space most of the contents of both galaxies would be just fine. Could a similar effect be responsible for the late heavy…
Sarah Szabo
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How did asteroid (7482) 1994 PC1 get its "face"? Is it reconstructed from optical or radar imaging, or something else?
(Image sources linked below)
NPR's March 10, 2023 Newly found asteroid has a 'very small chance' of hitting Earth, NASA says includes an image of what looks like a computer reconstructed 3D surface of an asteroid, perhaps from delay-doppler radar…
uhoh
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How would "dark matter", subject only to gravity, behave?
If we were to hypothesise that the Universe contained a significant mass of "dark matter" particles subject only to gravity, presumably general relativity would give us a good idea of how they would behave.
For example, what would happen in a region…
mikado
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13
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2 answers
Why hasn't VLBI been used to try and image giant exoplanets?
A Jupiter-sized object at 10 pc subtends an angle of 0.0001 arcseconds (100 micro-arcsec) at the Earth. The Event Horizon Telescope interferometry network is capable of a (demonstrated) angular resolution of about 20 micro-arcseconds.
Why haven't we…
ProfRob
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Has NASA released any JWST images of Trappist-1? If not, why?
According to JWST weekly schedules (found here), the Trappist-1 system was among the telescope's targets during early July.
The only JWST image of an exoplanet in the Trappist-1 system that I've managed to find was posted by a redditor (as explained…
William
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Is Dark Matter possible if there is dynamical friction?
If dark matter existed: wouldn't it slow down the orbital velocity of stars in galactic disks by dynamical friction more than it would accelerate them through additional mass? The original orbital momentum of the galaxy and the effect of its…
Reggie Grünenberg
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13
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Can gravitational waves transfer energy or momentum to baryonic matter
In essence I want to know if GW can affect the momentum of baryonic matter. I know that massive objects like planets, stars, galaxies, etc will not be "ripped apart" or even disturbed by even the most massive GW from a SMBH major merger. But what…
NotSoSN
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