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1500 questions
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What is the fastest spinning rotation of a Neutron star?
What is the fastest spinning rotation of a Neutron star? I have heard that Neutron stars have a specially fast spinning rotation. What is the fastest?
Jamd
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How is the first detonation in Supernove type Ia triggered?
Ok, I read about the Supernova of type Ia and I found out that there are two detonations happening. First one is in helium shell around the white dwarf and second one seems to be triggered by the first one and it is the main part of whole supernova.…
Vojta Klimes
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What was the largest telescope ever fitted with an eyepiece
Serious modern telescopes use CCDs to capture the results. This makes it convenient to process or display the results halfway around the world. However, there is something visceral about looking through an eyepiece and seeing the results live.
My…
Daniel Griscom
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What are the Earth-like features of Titan?
This NASA site says that hidden beneath the smog of Titan are Cirrus like clouds and This space article describes how Titan's atmosphere is similar to Earth's too.
What other features does Titan boast that make scientists so ready to boast that…
user96
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2 answers
Is there a ninth planet?
After Pluto's demotion as a planet, we have currently eight planets in our solar system. But Sun's gravitational pull can be felt well beyond Pluto, so is it possible to have a ninth planet beyond Pluto? I asked this question because we have Kuiper…
Kushal Bhuyan
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Subterranean Oceans On Other Planets/Planetoids: How Do Astronomers Deduce This
Recently I have been looking into planetoids in our asteroid belt and I have found one that caught my interest, Ceres. One of the main points that was said about it was that it had a subterranean ocean. But I'm puzzled as to how astronomers can come…
The Contextual Path
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Why are the magnetic poles of a pulsar so far off the rotational axis, yet stable?
My understanding is that a pulsar is a neutron star whose magnetic poles don't coincide with the rotational poles and whose magnetic poles sweep through Earth (allowing us to hear radio noise).
If we keep hearing pulsars, the polar offset must be…
Bohemian
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two black holes orbiting each other within their event horizon
Is there any argument against this situation: two black holes, one within the event horizon of the other, and the system is stable.
It is interesting to me because that if this works, we could have the system's event horizon not in the shape of a…
Köksal
12
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2 answers
The battle over Gliese 581 and Gliese 667C?
In 2014, Robertson et al. made a case that stellar activity is masquerading as planets (here and here) for these well-known systems. In both cases, they claim that the only real planets discovered so far are planets "b" and "c". In 2015,…
Jack R. Woods
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Is any consensus forming on the solution to the "Lithium Problem"?
The "Lithium Problem" relates to the fact very-low-metallicity stars appear to have a Li/H ratio approximately one third of what would be expected. The ratio should be the same as the prediction from Big Bang nucleosynthesis theory. A possibly…
Eubie Drew
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Is it possible to witness a star's death?
Given that the stars' distances to Earth are measured in light-years (for example, Sirius is 8.6 light-years away from Earth), what we are seeing as Sirius now is actually its state 8.6 years ago, right?
So it is possible that a star (maybe not…
jeff
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How do we calculate the escape velocity of galaxies?
How do we calculate the escape velocity of galaxies?
Do we have to know the total mass?
What is the escape velocity for Milky Way?
Claudia
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What's the smallest scale at which dark matter has been measured?
What is the smallest scale at which we have detected "dark matter" (more kinetic energy than would be predicted)?
If you don't mind indulging a follow-up: Would its detection on smaller scales be beneficial at all to advancing our…
Steve Clay
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Orbits in a binary star system
I know of three sets of stable orbits in a binary star system: orbiting closely around star A, orbiting closely around star B, or orbiting distantly around both stars (and their mutual center of gravity) at once.
Is there a fourth set of stable…
Mark
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Why are retrograde orbits more stable than prograde ones?
Regarding solar system dynamics, i.e. planets in stellar systems and moons in planetary systems, this is often mentioned in the literature, but it is difficult to find a good analysis/explanation of this phenomenon.
Fiasco Burnett
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