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1500 questions
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How much more life could the Sun acquire via star lifting?
It has been proposed before that we could use this technique to remove hydrogen from the Sun to lower it's rate of fusion and extend it's life, so it doesn't fry our planet.
I am wondering how much more life could we possibly get out of the Sun…
DennisCA
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Does the dimming of Betelgeuse present any observational opportunities?
Recent photometry suggests that Betelgeuse has been dimming over the past three or so months, reaching the faintest V-band magnitude seen in modern observations. The changes are apparently even visible to the naked eye, and appear to correspond to a…
HDE 226868
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Is it possible to see stars that are gravitationally lensed by the sun from the ground?
Roughly 100 years ago, Eddington confirmed Einstein’s general relativity theory by photographing stars behind the obscured Sun during a total eclipse.
A coronograph is a device that mimics what happens during an eclipse and blocks the light that…
usernumber
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How can I hear (or at least detect) a pulsar at home?
Scott Manley's video Using Relativistic Raytracing &X-Rays To See Detail on Surface Of Neutron Star talks about X-ray measurements using the NICER X-ray telescope attached to the International Space Station (Wikipedia, in SE: 2 & 3), results which…
uhoh
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Why would a black hole have a disk, but not emit x-rays?
There's a recent paper in Nature about LB-1, a B-class star orbiting a massive black hole.
I don't understand how these two parts of the paper can be reconciled. On page 2, the authors argue that the broad $H\alpha$ line indicates there's a disk in…
Allure
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Will James Webb see Population III stars?
I have heard that James Webb will see the first stars that our universe produced. Can I assume that we may see galaxies that are so young that all of the stars in them are population III?
Jack R. Woods
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Navigation using moon phases
How to navigate with possible maximal precision using moon phases?
The Moon is the brightest celestial body seen in the night sky, and it is possible to find even through moderate clouds. So it's a good natural object to use in navigation when a…
Danubian Sailor
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Is Earth's Surface "In orbit"?
I'm having trouble understanding relative angular/tangential speeds at increasing altitudes above Earth's surface. In particular, I find this comparison of tangential velocities on Wikipedia very confusing. According to it, the tangential speed of…
Rabadash8820
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Are the orbits of all triple star systems at least technically unstable?
Background:
In the Circular Restricted Three Body Problem (CR3BP, CRTBP) some halo orbits are mathematically stable. That means that the orbit of the third body is closed, periodic, and stable against small perturbations as long as the two primary…
uhoh
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Is it possible to see mercury transit "clearly" by the naked eye?
I don't have a telescope but I'm interested in seeing events like eclipses and transits.
I'll use the atmosphere as my big natural lens. So I'll watch the upcoming mercury transit at the sunset time where the sun looks bigger than usual. Will this…
user2824371
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Could a star closely orbit a black hole long enough for the star to have lost 0.5B+ years to time dilation?
I was wondering how stable a close star-black hole system could plausibly be, and thus how much time a star could plausibly miss out on (from an outside observer's perspective) due to being in an orbit at relativistic speeds around a black…
Jacob C.
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antimatter annihilation in stars
Electrons annihilate with positrons produced through fusion processes in stars. Which particle interaction produces new electrons so that the sun isn't deplete of electrons? Or is something else happening altogether?
Regular fusion cycles in stars…
Josh Bilak
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Could this estimate of the size and mass of the Chicxulub Impactor be accurate?
My understanding has always been that the Chicxulub Impactor was in all likelihood an asteroid with a diameter of about 8 - 12 km, but then, the other day, I came across this paper. In it, they say that the diameter of the impactor could have been…
Happy Koala
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What is this "Table of astronomy" about?
I found this picture while looking for some tattoo ideas and would like to know what these sketches are supposed to mean.
Im especially interested in figures 1, 21, 53 and 56.
It appears to be a scan of page 164 of the Cyclopædia (an Universal…
nuuse
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On the consistency of different well-polished astronomy software
I have purchased a custom wedding band from a seller that claims the ring will show the constellations visible at the horizon on a specific date at a certain date and time.
However, I have fired up Stellarium and set it up to look at a specific…
Mister Mystère
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