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1500 questions
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Why does the CMB conform to black-body formula for 2.71 degrees, when it's the stretched emission at a far hotter temp?
Physicist Chad Orzel in "Einstein's Legacy" discusses Planck's Black-Body formula, stating that it fits perfectly to everything we see, from toasters to stars. Fine. Then he says it perfectly describes the radiation curve of the CMB as belonging to…
GulbenkianD
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Could we detect dark matter by black holes gaining unexplained mass?
Dark matter is said to interact only gravitationally, so it won't commonly form black holes by itself. But if a black hole is already there, and dark matter encounters the event horizon, it should go in and never come out. This means black holes…
Hene
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What actually are line-driven winds?
I have read several books (viz. intro to stellar winds)/articles about stellar winds (dust-driven, line-driven, coronal winds), but still didn't understand the explanation. I understand that line-driven winds occur in hot and high-mass stars, but I…
aapnegara
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Which of the exoplanets are having retrograde rotation?
By exoplanet, I mean planets outside of our solar system(i.e., planets in other solar systems). If we talk about our solar system, then Venus, Uranus, and Pluto have retrograde rotation. Most of the planets in our solar system rotate…
apk
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What causes the halo in JWST's new image of Jupiter?
Then new JWST image of Jupiter shows a small halo on the right side of the planet. What's causing this feature? I figure it could be that the planet is simply overexposed (or moving slightly during the exposure?). Or perhaps this is a phase…
user2944352
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What is this object visible in the Chandra image of the Cartwheel galaxy that isn't visible in JWST image?
In the below images I aligned an image from Chandra of the Cartwheel galaxy over the image from JWST. The first is the Chandra image pasted on top, fully opaque. The second is just the JWST image, and the third is the Chandra image over the JWST…
MVTC
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Is there anything currently 46 billion light years away from Earth that we can see?
If the oldest galaxy ever discovered, i.e GLASS-z13, is at a present proper distance of around 33 billion ly from Earth, why then do we define the observable universe to have a radius of around 46 billion ly? Is there anything currently 46 billion…
William
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Where is the barycenter of the Milky Way Galaxy?
Is the barycenter of the Milky Way Galaxy located within the supermassive black hole, or its event horizon, at the center of our galaxy?
Bob516
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What are the black spots/blobs in JWST Jupiter's images?
Consider these two recent JWST images of Jupiter:
Europa is shown as the black circle. In the second image, Europa's shadow can be seen near Jupiter's big red spot (white in the image, since it is in IR wavelengths).
However, there is an irregular…
Victor Stafusa - BozoNaCadeia
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How do we know the hydrocarbon lakes on Titan are actually liquid?
Cassini failed to detect any waves in the seas/lakes it observed, despite winds of 72 km/h (45 mph) being present on Titan which are able to create "sand" dunes from frozen particles, and with milimeter precision nothing turned up. They appear to be…
Axion
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Gravitational mirroring: Can we theoretically see the Milky Way using a telescope?
As I am watching the beautiful deep field picture of the James Webb Space Telescope. I noticed the gravitational lensing. So I asked myself whether it is possible somehow a successive cluster of galaxies or black holes forming a mirror instead of a…
user50618
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How do astronomers distinguish between Cepheids and other types of variable stars?
So my understanding of how Cepheid is used as standard candle to determine distance of galaxies is like this: Astronomers observe a galaxy, notice an object within that galaxy whose brightness pulsates periodically, measure its period, translate it…
mudiwii
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Where's the matter that created the CMB?
I know that the CMB was created at the recombination, when photons could finally travel freely. But each of those photons was deflected one last time before this happened. Where's the matter that deflected the photons? Has it become the baryonic…
zucculent
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JPL Horizons - "highly accurate measurements of planetary positions" - how do they do it?
According to JPL Horizons, with regard to their planetary position calculations,
... we integrate the equations of motion in Cartesian coordinates
($x,y,z$), and we adjust the initial conditions in order to fit modern,
highly accurate measurements…
Peter
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Why is the ring in this simulation of Sgr A* off center?
In the recent releases of images of Sgr A*, simulated versions of what they expected were included along side the actual images they were able to get. What confuses me about these simulated images (and I believe this was the case for M87 as well) is…
Justin T
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