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1500 questions
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Will the Vera C. Rubin Observatory (formerly the LSST) make a significant increase in the rate of astronomical event alerts?
The NPR news article and podcast New Telescope Promises To Revolutionize Astronomy updates the status of the "Large Synoptic Survey Telescope under construction on Cerro Pachón in Chile".
NPR's Joe Palca's piece includes sound bites from…
uhoh
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Kepler space telescope undetected planets
The Kepler space telescope detects planets based on the dip in brightness caused by planets moving past the star.
Wouldn’t that mean that there are an unknown amount of planets that have an orbit that wouldn’t be detected because their orbits don’t…
griffins
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Official degrees of earth’s rotation per day
What is the official degree to one decimal point please, of the earth’s rotation in one single day. Can it be confirmed that it is exactly 360.0 degrees using official data? Thank you in advance.
Autodidact
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How would the Tycho Impact have appeared from Earth?
The Tycho crater is thought to be the youngest major impact on the Moon, estimated at 108 million years ago. This puts it firmly in the reign of the dinosaurs, I find myself curious as to what our thunder-lizard brethren would have…
MichaelB76
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Could stars form outside of galaxies?
Is it possible for there to be a dense enough nebula to form stars outside of any galaxy? Does a galaxy have a minimum size to produce stars? Or could you have a few dozen stars clustered together by themselves?
Lorry Laurence mcLarry
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What is the "lost light" in this unusual Hubble Deep Sky image?
The Daily Galaxy article “The Lost Hubble” –New! Deepest Image of the Universe Ever Taken says:
To produce the image a group of researchers from the Instituto de Astrofísica de Canarias (IAC) led by Alejandro S. Borlaff used original HUDF images…
uhoh
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Is Optical VLBI theoretically feasible? If not why not?
There are plenty of optical interferometers in use with baselines of up to maybe 1km. As far as I can find out, they all work by directly collecting the light at all the telescopes, using mirrors to bring them together and then actually interfering…
Steve Linton
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In which direction is the sun travelling?
Relative to this simple drawing, can someone explain to me,
in which direction is the sun and its solar system travelling,
which star (irrespective of distance) is closest to that direction,
and in which direction the milky way center is.
Alonda
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How does the Moon look like from different latitudes of the Earth?
I have heard, that on the northern hemisphere, you can estimate a direction of south if you imagine a line going through the tips of the border between illuminated and shadowed part of the Moon, and where this line crosses the horizon, that is…
user50222
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Do any known exoplanetary/solar bodies have "annular" eclipses similar to Earth's?
This was somewhat inspired by this question but is a bit different: I am interested in if there are any known systems in which the angular size of the eclipsing object is almost the same as the angular size of the object being eclipsed from the…
Guillochon
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When will all eight planets in our solar system align?
Ignoring expansion of the universe, entropy, decaying orbits, and interference from any bodies colliding with or otherwise interfering with their orbits, will the eight planets known planets in our solar system ever align?
What is the "period" of…
IQAndreas
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Is there a maximum size for a black hole?
As far as I understand it black holes radiate Hawking radiation and probably gravity waves, which over time causes them to lose mass and eventually evaporate after almost unfathomable amounts of time. I've also read that black holes eventually have…
Mark Rogers
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Shape of neutron stars
I've heard that the more an object spins, the less of a true sphere it is.
Using this logic most of neutron stars would be far from spherical,in general what shape are most neutron stars?
kingW3
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Does the observed period of a pulsar change with the time of year?
Over in the Physics SE a question was posted asking about the difference in the time dilation of the Earth between perihelion and aphelion:
Does Earth experience any significant, measurable time dilation at perihelion?
Rather to my surprise it turns…
John Rennie
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Can this picture of the moon directly above the sun from the horizon be real?
I recently saw this image, but somebody told me that it is fake, possibly photoshopped. The moon and the sun appear to be on the same perpendicular from the horizon. Is there any way to tell if this shot was actually captured?
Ali Ph
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