B--rian
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How can astronomers pinpoint the location of the source of a neutrino?
23 votes

You correctly state that neutrinos do not interact too often. The physical parameter describing that is the effective cross-section. So what you observe in a detector is not the neutrino itself, but ...

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How loud was the asteroid that killed the dinosaurs?
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15 votes

Some estimates which I found worth sharing: For fun, I searched for Chixculub TNT equivalent and e.g. ScienceDaily claims The energy released by the impact that blew out the Chicxulub crater was ...

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Why was Neptune rather than Uranus chosen as an archetype?
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9 votes

NASA distinguishes four types of exoplanets: Gas Giant, Super-Earth, Neptune-like, and Terrestrial. The question asks why ice planets termed "Neptune-like" and not "Uranus-like". ...

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Role of power laws in astronomy?
8 votes

I have to admit that power-laws (in general) used to be my shtick so I am happy to shed some light on their general importance in physics which obviously also hold for astronomy. The main idea of a ...

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Spotting the booster rocket of the Chinese space station?
7 votes

I found an openly available CZ-5B Rocket Body (ID 48275) reentry prediction: Most intersting I found the following graph which shows how slowly error bars of the predicted reentry time decrease over ...

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How many space telescopes are currently active?
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7 votes

More than 20 if the Wikipedia's List of Space Telescopes is accurate. I extracted the active ones, and removed duplicates (to the best of my knowledge): Swift Gamma Ray Burst Explorer AGILE FGST ...

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What is the best database for identification of spectral lines?
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6 votes

There is the NIST Atomic Spectra Database where you could browse by elements. This the reverse approach, meaning that you have to first query element by element and then see which of the lines you ...

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Which will destroy the Earth first: the Sun or Jupiter?
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6 votes

I found an article by Ian O'Neill posted on May 2, 2008 at universetoday.com with the title Could Jupiter Wreck the Solar System? which says But here’s the kicker: There is only a 1% chance that ...

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Why temperature of dark side of moon is not 3 Kelvin
5 votes

The "dark" side of the Moon is only truly dark during full Moon. Everywhere on the Moon there is day and night as well. The dark side of the Moon is called like that because we do not see it ...

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Is there any difference between M87's image and predictions?
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5 votes

The observation did indeed confirm general relativity, see e.g. Lisa Grossman wrote in October 2020 for ScienceNews: The first black hole image helped test general relativity in a new way That iconic ...

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Are any supergiants translucent?
4 votes

Although I will only tackle one part of the question, I find the following part of a picture from NRAO/AUI/NSF, S. Dagnello, cited from space.com worth sharing: You see the radial structure of ...

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When was H-alpha first used to observe the universe?
4 votes

Seemingly easy question, but actually not trivial to answer. Wikipedia on H-alpha as well as other entries in other encyclopedias obviously mention the Balmer series and that the spectral line was ...

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What are the raisons d'être for the Large Binocular Telescope "binocularity"?
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4 votes

I asked myself the same question and back then, I found the reasoning on the German Wikipedia page pretty comprehensive. I am translating, summarizing and expanding the corresponding section in the ...

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How much higher is the radiation around Jupiter than at Chernobyl, after the explosion?
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4 votes

Let's first quickly estimate whether the numbers by HBO's TV series make sense: According to gesundheit.ch/strahlung the liquidiators were exposed to $2 \ldots 20 {\rm Sv}$ which compares to a life ...

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Why do people choose 0.2 as the value of linking length in the friends-of-friends algorithm?
4 votes

A quick search brought me to a book by Houjun Mo, et al. Galaxy Formation and Evolution which says For example, the frequently used friends-of-friends (FOF) algorithm defines halos as structures ...

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Could diatom blooms affect albedo of an exoplanet?
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3 votes

First off, I am rather certain that by diatom bloom you refer to algal bloom which is a seasonal change of sea color, at least here on Earth, the only system we have observed yet. Your question is ...

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How much is usually deposited in a Mars regional dust storm?
3 votes

Philip R. Christensen wrote an article back in 1986 called Regional dust deposits on Mars: Physical properties, age, and history. The abstract says Dust deposited during global storms is subsequently ...

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Why would the Chang'e-4 lander find lunar far side temp. "colder than scientists expected", when the LRO has already been taking thermal readings?
3 votes

I would not attribute too much importance to the quote "colder than expected", because that always depends which expectations one had initially. Here the quote you are discussing: ...

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Who discovered Wolf 359?
3 votes

For me, it looks like Max Wolf discovered the movements of the Wolf 359, see the (German) original publication from 1918 "Zwei Sterne mit großer Eigenbewegung in Leo," but he does not ...

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Calibrating raw photometric measurements
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3 votes

If I understand the question correctly, you have raw data from a CCD sensor in arbitray units (which correlate with brightness) and your challenge is to callibrate this intensity for a certain ...

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How does Io's atmosphere behave locally near volcanic plumes?
3 votes

My impression is that for answering your question, one would actually have to run simulations, ideally so-called global circulation models (GCM). If this is for a research project, the MIT GCM would ...

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Do we finally have a decent set of parameters of 162173 Ryugu?
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3 votes

A science paper from 2019 by K. Kitazato et al. shows a shape model of the surface in Fig. 2, so we now indeed know the exact size and the exact mass, even the surface temperature distribution: The ...

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What is happening with these solar particles detected near the Sun that is so newsworthy?
3 votes

If I understand your question correctly, it is about EPI-Lo which a part of the Integrated Science Investigation of the Sun (ISʘIS) . The picture is also taken from there: EPI-Lo stands for Energetic ...

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Counter clockwise rotation of storms at Jupiter's north pole. What explanations have been proposed?
3 votes

Let my try to stretch the analogy to anticyclonic tornados: The vast majority of all tornados move cyclonic, i.e. counterclockwise on the Northern Hemnisphere of our blue planet. There is e.g. a ...

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Would we detect a spacecraft before it landed on Earth?
3 votes

Some thoughts about Earth-based detection systems: We are looking at asteroids using radar: For instance the former Arecibo telescope could actively send out radio waves and calculate object position ...

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How far away was the binary black hole that produced GW170729?
2 votes

The LIGO science collaboration site is the official source (highlighting is from me): Of the ten BBH systems in our catalog, six have estimated distances of about a Gigaparsec (1 Gpc = 1 billion ...

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Unsure how to obtain galactic roll?
2 votes

For an aircraft there are three principal axis: Pitch, roll, and yaw. I never heard the terms used in astronomy, but it does not seem to be too far-fetched in your setup, so I am confident: A roll-...

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Can I find exoplanets without a telescope?
2 votes

No. With a probability nearly equal 1 you will not find any exoplanet with naked eye from Earth, even under perfect conditions like no light-pollution. The human eye simply does not have enough ...

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Were there any images of Sanduleak -69 202 (progenitor of SN1987A) before it exploded?
2 votes

Another link worth sharing comes from ESO and is called The Large Magellanic Cloud before and after SN1987A. The link mainly shows the following

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What is the gain of a telescope?
2 votes

Gain in electronics can have different meanings: Gain is a measure of the ability of a [...] [device] to increase the power or amplitude of a signal from the input to the output port. [...] The term ...

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