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1500 questions
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Will Asteroid (2021 LD6) be visible to the naked eye?
There's a lot of hoopla online about asteroid 2021 LD6's close approach to Earth. Will be close enough and large enough to be seen with the naked eye?
PS: More on the object: MPC or JPL
Rob Adams
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What is that donut-shaped object I see in my telescope?
I was looking through my telescope for the first time and came across this weird star. I think its a celestial donut but im not sure.
Mani S
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Is the universe macroscopically transparent to CMB? Is the fraction intercepted by stars and dust so tiny that it doesn't have a correction factor?
Background
The question Why do some electromagnetic waves continue travelling while others disappear? is interesting, and in addition to the answer there I started to write:
This is a supplementary answer to @ConnorGarcia's answer using the example…
uhoh
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Does bending of light around the Sun depend on the wavelength?
If the energy of light is high, does its curvature differ from that of low-energy light around the Sun? In other words, if the wavelength of the light is shorter than another wavelength of light, then does the bending of the two lights differ around…
Red Bel
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What implications do younger Earth and Moon have on Late Heavy Bombardment genesis hypotheses?
The Late Heavy Bombardment (LHB) or the Lunar Cataclysm is when the inner solar system, including the Earth and the Moon, underwent multiple and sustained heavy impacts early in their history (around 3.7-4 billion years ago). This event formed many…
user8
13
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2 answers
If GRB 080319B happened next to nearest star: Proxima Centauri, what effect would that have had on us?
From a Reddit post
GRB 080319B was a gamma-ray burst (GRB) detected by
the Swift satellite at 06:12 UTC on March 19, 2008. The burst set a
new record for the farthest object that was observable with the naked
eye: it had a peak visual apparent…
Tom Sol
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Does a meteor's direction change between country or latitude?
So here is the question me and a friend of mine from Norway we saw a meteor but que said he saw it in the opposite direction as me and I was looking from spain, does that make any sense? Or we should see it going the same direction? Thanks in…
user38404
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How is it possible for a collision to be responsible for Uranus's axial tilt?
I realize that the collision explanation is in any case highly (purely?) speculative, but I'm curious how it would work. If Uranus is a ball of gas, why wouldn't any colliding object just pass through (or perhaps be destroyed/significantly damaged…
Kurt Weber
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Is it at all possible for the sun to revolve around as many barycenters as we have planets in our solar system?
Though it is understandable that the sun and the earth may be revolving around a barycenter, but, if so, not only the sun and Jupiter should also be revolving around some barycenter, the same should be true about the other planets as well? So it has…
S C Sawhney
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What is the predominant element in the dust of the Sombrero Galaxy?
The Sombrero Galaxy contains a rather peculiar ring of dust orbiting it (seen as the dark ring on the outer edge). What is the prevalent element in this dust? Carbon?
user19
13
votes
1 answer
How loud was the asteroid that killed the dinosaurs?
Asteroid impacts on the Earth can be very loud when they break up in the atmosphere, like Chelyabinsk, captured in this video:
The Chelyabinsk asteroid break-up was estimated to be about 180dB at 3 miles, and was detected as far as 9000 miles…
Connor Garcia
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8 answers
Do our sun and moon have names?
We seem to have named every moon orbiting other planets. Why haven't we named our own moon? And for that matter, why doesn't our sun have a name since we name or number stars?
Bookaholic
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How is it possible that Saturn's gravitational acceleration felt by Mimas is stronger than Mimas' own surface gravity?
The surface gravity on Mimas is $≈ 0.063\text{ m}/\text{s}^2$ and Saturn's gravitational acceleration at the distance of Mimas' orbit is:
$$\frac{{GM}}{{r}^2} = \frac{{6.674 \times 10^{-11} \times 568.34 \times 10^{24}}}{{(185.52 \times 10^{6})}^2}…
ChristieToWin
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If the axial tilt of Uranus (97°) was caused by a giant impact, then why do its moons orbit around its equator at the same tilt (≈97°)?
So the most accepted explanation for Uranus' axial tilt is that it once had a normal tilt like the other planets bar Venus (0° to 30°), but then a certain massive object collided with it and flipped it on its side.
But by that logic then shouldn't…
user177107
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Is it possible to see Callisto with the naked eye when it's at its greatest elongation from Jupiter?
A quick search shows that Callisto has an apparent magntidue of 5.65, which would make it easily visible under relatively dark skies. Being the farthest Galilean moon, does it ever get far away from Jupiter for it to be discernable to the naked eye?…
user177107
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