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1500 questions
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Role of power laws in astronomy?
I often see astronomers fitting data to power laws. What about power laws makes them so useful in astronomy? Why are so many astronomical observations well-fit by power laws? I know it's a relation between two quantities, but why is a power law the…
blackhole
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Can an entire star pass through the event horizon of a black hole unharmed?
Can there be any black hole big enough that a regular sized star can pass through its event horizon unharmed?
S. M. JAHANGIR
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Is there a precise definition of "Supermoon"?
Elsewhere online I keep reading that a supermoon is the situation when full moon coincides with moon perigee. But see this plot from wikipedia Lunar Distance entry
The perigee distance varies wildly across the year, so we could have "supermoons"…
arivero
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What observational constraints are there in detecting the presence of volcanism on exoplanets?
This question is somewhat related to my earlier question How are the compositional components of exoplanet atmospheres differentiated?, but this about a specific surface-atmospheric phenomena - volcanism.
Using our solar system as a rough analogue…
user8
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How do we know that supermassive black holes can gain mass by means other than merging with other supermassive black holes?
I just stumbled across the following answer "update" from 2013:
This just in, recent observations have ruled out the possibility that SMBHs gain mass only through merging with other black holes. For more, see this Astronomy.com article.
Question:…
uhoh
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Is there a closest free-return trajectory to a black hole?
The scenario I am imagining is a test particle falling from infinity with an initial off-center velocity. In Newtonian mechanics the path would be a hyperbola. But I assume that, near a black hole, that is no longer a good approximation.
I have read…
Mark Foskey
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Why (the heck) is the basic angle of GAIA 106.5°?
This answer to Why does the Gaia space telescope have two main mirrors says:
According to the GAIA FAQs which does an excellent job: http://www.cosmos.esa.int/web/gaia/faqs:
Why is there an angle of 106.5 degrees between Gaia's 2 telescopes?
The…
uhoh
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Can one build a distributed radio telescope?
I understand some radio telescopes are built as arrays of receivers. Could one build an array from a heterogeneous set of receivers in scattered locations? Suppose a large number of persons each operate a receiver, and data is gathered together; can…
Joe Cooper
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How can orbital resonance sometimes have a stabilising effect, whilst other times, it has a destabilising effect?
I have just started learning about orbital resonance. I understand how bodies in orbital resonance will line up according to the orbital ratio number, and there will be increased gravitational effects upon alignment.
However, I do not understand how…
Matthew H
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What are the challenges in finding Earth-like planets via the radial velocity method?
[I have re-asked this, because it was a good question by @Banyan, which was deleted whilst I was composing an answer.]
Most exoplanets that are found by the radial velocity ("Doppler wobble") technique are quite massive - Jupiter/Saturn-like…
ProfRob
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Why can't we build a huge stationary optical telescope inside a depression similar to the FAST radio telescope?
So first we'll have to find a natural depression or we should create one. I understand you can only see a single portion of the sky since it can't be moved, so my money is on creating an artificial basin in an area where directly upwards it has the…
AKR
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Observatories that allow public access
Are there any observatories with high powered telescopes that also allow public access?
Astronomy is a VERY expensive addiction, because no matter what telescope you get, you always want the next model up. If we can find an observatory that allows…
Bookaholic
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Spatial wind speed distribution on Mars using dune shapes?
As a fan of exometeorology (the study of atmospheres of other planets), I scanned through a whitepaper Measuring Mars Atmospheric Winds from Orbit which says
Measurements of Mars
atmospheric winds from orbit would dramatically advance our…
B--rian
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How do we get to know the total mass of an atmosphere?
Since atmospheres don't end abruptly but gradually get thinner the higher you go, I wonder how we can get the total mass of an atmosphere if we don't know where exactly it ends. E.g. the Earth's atmosphere's mass is defined as 5.1480 × 1018 kg. Does…
Greenhorn
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Are stars near the ecliptic the only stars from which Earth would appear to transit the Sun?
The majority of exoplanets we have discovered have been found by the transit method, in which a planet passes in front of its parent star and by analyzing the light curve we can deduct its characteristics.
Say there was intelligent life around a…
user177107
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