Questions tagged [history]
Questions regarding the history of astronomy, including discoveries and scientists.
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Credible description of point sources and point spread functions in astronomy
I am looking for a credible source (or even the original sources) that describe point sources and/or point spread functions (PSFs) on astronomy.
Unfortunately, the Wikipedia pages (point source, PSF) ...
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Was Galileo expecting to see so many stars?
Beginner amateur here. I see mentioned many times that Galileo was surprised to see the moons of Jupiter and all that their existence proved, i.e. the Earth not necessarily being the center of ...
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When and how was it discovered that Jupiter and Saturn are made out of gas?
Was it due to appearance only or spectroscopic methods were used? Venus also has a thick cloud cover, how was it determined to be a rocky planet?
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What is this drawing about in "kitab al bulhan"?
Kitab al bulhan or "book of surprises" is medieval Persian manuscript written in Arabic.
According to Wikipedia:
The contents include subjects on astronomy, astrology and geomancy, ...
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About Year Zero
It is said that, in part due to a poor grasp of mathematics (the number zero to be precise) our forebears, when they developed the calendar went from 1 BC/BCE to 1 AD/CE. Year Zero is missing - it ...
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First time mention of coplanarity between Solar Systems planets
When comparing Galileo, Copernicus and Hypathia models to describe the solar system, each of them agree on coplanarity, based on their representations. Anyways, it was not until Kepler and Newton that ...
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What's the issue with Olbers' paradox?
I'm not quite grasping the reasoning behind Olbers' Paradox, or why an eternal, non-expanding and spatially infinite universe would be incompatible with a dark sky. For simplicity, let's suppose that ...
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What is the brightest nameless star?
Bright stars in the night sky traditionally have their own proper names, like "Sirus" or "Canopus".
Most stars don't have names, but instead catalogue identifiers, like the Bayer ...
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Is pointing a telescope at a random place a viable astronomical strategy?
Recently I happened to be on the MAST portal, looking at jwst data. I happened to come across 2 interesting targets, “random place” and “another random place”
This got me thinking. It’s almost ...
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First satellite of an asteroid (or double asteroid) ever imaged by delay-Doppler radar?
In comments about my previous bounty on the Space SE question Which deep-space spacecraft flew closest by Earth during a gravitational assist?, I started to look at the Galileo mission and ran across ...
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Did de Sitter expect to disprove Ritz theory only with visual binaries?
Walter Ritz’s emission theory stated that some fraction of the velocity of an object was added to the speed of light emitted from it. Willem de Sitter pointed out a problem with this in the case of a ...
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How was the First Point of Aries measured in ancient times?
According to Wikipedia, usage of the Sun's position as the basis for a celestial coordinate system dates back at least to Babylonian times, and the current "First Point of Aries" system ...
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Which world did Carl Sagan know of with a million moons?
I recently read Carl Sagan's The Cosmic Connection. In it, he begins the seventh chapter with a series of claims to depict the universe as "vast and awesome."
I'm particularly interested in ...
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Early Milky Way depictions after Herschel?
We are all familiar with the 1785 drawing of the Galaxy by William Herschel, often quoted as the "First drawing of the Milky Way"
Are there any other such historical drawings after this one?...
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At what point in history was the idea of planets being spit out by the sun abandoned?
For context, at some point during the 20th century (and maybe earlier as well), the most popular planet formation theory and the one that was taught at (at least some) schools was the theory that the ...
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History, significance and "drama" (if any) of T-Tauri stars, especially the early bits?
In this answer to Can I write a systematic review as an undergraduate and get it published in a journal? in Academia SE I recounted my memory of an experience from circa 1980:
I had an initially ...
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What else can we learn from a Foucault pendulum? Have they ever been used to determine anything more than that the Earth rotates on its axis?
Background
Each semester we have to make up projects for each course. This semester I took Cosmology and Astrophysics and we covered a vast amount of topics, from luminosity of stars to Einstein's ...
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How much energy to shorten a synodic month by about 1.56%?
Suppose the moon underwent a single, massive, large-object bombardment event. About what number (or range) of about what mean mass of objects could shorten the synodic month by about 1.5633%?
(Assume ...
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Doubt about a computation in Jules Verne
In his Aventures de trois Russes et de trois Anglais dans l'Afrique australe (The Adventures of Three Englishmen and Three Russians in South Africa), Jules Verne describes in some detail the geodetic ...
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Empirical findings, Occam's razor, and the replacement of Ptolemaism by heliocentrism [closed]
C. S. Lewis's book The Discarded Image is about how to understand and how not to misunderstand medieval literature. In some parts he explicitly contrasts medieval with modern culture. In one of those ...
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Why orient a refracting telescope to the North?
I'm a french Guide of french military heritage. I have to prepare visit about "L'observatoire de la Marine, moulins du faouëdic" (Former windmill which served as an astronomical and ...
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Examples of the oldest "precoveries"; objects that were first discovered in recent data but then looking back are confirmed in much older data
Example from Ars Technica's Radio astronomers scouring the archives spotted black hole devouring a star:
Astronomers found another TDE in 2020 (dubbed AT 2019qiz), which provided the first direct ...
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How long would it take to realize there are "star-like objects" (i.e. planets) that change position in respect to the "fixed stars"?
If you were using unaided observations and were unfamiliar with astronomy (and maybe just pen and paper for recording anything), how long should it take to notice that Mercury, Venus, Mars, Jupiter ...
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Did astronomers ever use photographic plate rotation along with alt-az mounts?
The video Earth's Rotation Visualized in a Timelapse of the Milky Way Galaxy - 4K (linked below) and discussion below this answer to Why does a timelapse video of a stationary Milky Way make the ...
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Why are there 12 zodiac signs?
My friend and I are arguing whether it is because there are 12 months or there are 12 constellations along this path. It makes more sense to me that, since there are 12 months, they divided the path ...
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What was "wrong" about the motion of Neptune in 1984?
The cover story of the March 1984 issue of RUN, a popular computing magazine, was written by noted astronomer Charles T. Kowal. In the article, he describes how he uses his home computer, a Commodore ...
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Was lunar libration first observed or first predicted? In either case, who was the responsible party?
How old is the idea of the far side of the Moon? got me thinking that as soon as we see the moon librate we have to come to terms with there being even more of it we can't see.
The Moon's libration is ...
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How old is the idea of the far side of the Moon?
The far side of the Moon is the side which always faces away from the Earth, due to tidal locking. Due to libration, about 18% of this far side can be seen at one point or another through telescopes.
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How was the speed of the Sun (around the Milky Way Galaxy) calculated?
The Sun travels around the Milky Way Galaxy with a speed of 220 km/s. The question is: where did this value come from? Is there any article about the calculation?
Reformulated question: What are the ...
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What does 's' or 'ds' or $ds^2$ mean in the Schwarzschild equation(s)? [closed]
And:
These are from Wikipedia on Schwarzschild metric, Derivation of the Schwarzschild metric and the last is from Science Direct, Schwarzschild metric.
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What do "P" and "F" mean in the compass legend of Carrington's sunspot drawing?
In Richard Carrington's drawing of sunspots, he has a compass labeled "N", "P", "S", and "F". If "N" is North and "S" is South, what do &...
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How exactly was Giovanni Cassini able to measure the distance to Mars?
Recently learned that Cassini was able to calculate the distance to Mars quite well using parallax in 1672. I was surprised, since even at opposition of Mars, the parallax (with respect to the Earth's ...
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Why does the difference between terrestrial times and universal time, $\Delta T$, have such a strange behaviour?
I was reading about ancient astronomy, and one of the main phenomena described is eclipses. Now, I read this 2016 paper by Stephenson, Morrison and Hohenkerk, in which they determine the values of the ...
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Was the Nobel prize for gravitational waves handed out based on a hand-drawn theoretical curve? Has the data been fit more rigorously now?
In Sabine Hossenfelder's November 2019 video "Have we really measured gravitational waves?" (transcript, video), Sabine mentions the now famous image of the generally agreed-upon-to-be-very-...
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Did a watch company really try to sue radio astronomers for using the word "pulsar"? If so, which astronomers?
After about 48:37 in the really wonderful video Jocelyn Bell Burnell Special Public Lecture: The Discovery of Pulsars (linked below) Dr. Bell Burnell describes the ...
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What two "little observatories" run by a university in Chile and "by Germans" are near the future site of the Extremely Large Observatory?
Brady Haran is known for the Numberphile and Periodic Table of Videos YouTube channels but also does Deep Sky Videos.
In the video for the Extremely Large Telescope Haran stands at the site of the ...
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How was Theia discovered?
The Moon might have been created by the impact between the Earth and a Mars-sized body named Theia. Theia no longer exists, so when and how was it discovered? What clues led to the Theia hypothesis? ...
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Are there any old/ancient star maps that we can compare to today’s and see drastic differences?
Stars move through the sky very slowly, which is not noticeable in a human lifespan. I’m aware of proper motion of Barnard's Star and things of the sort but I’d like to obtain a noticeable record of ...
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Which A. M. Fridman is the author of this paper on gravitational stability?
Is this paper on globular cluster stability still up to date? links to The Stability of Globular Clusters and Spherical Galaxies. by A. M. Fridman of the:
Institude of Nuclear Physics, Siberian ...
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How did the measured diameter of Ceres evolve over time?
Based on the Wikipedia page of Ceres, Herschel measured a diameter of 260 kilometers for Ceres, and Schröter measured 2613 kilometers.
I do remember seeing at least a half-dozen estimates of the ...
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Why did the famous Multiple Mirror Telescope (MMT) get rid of them and become the Massive Monolithic Telescope?
Popular Science's 2016 article The silliest names scientists have given very serious telescopes... Ranked! says:
Arizona’s MMT Observatory used to house the Multiple Mirror Telescope. In 1998, ...
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When was H-alpha first used to observe the universe?
The H-alpha line is used by astronomers to trace the presence of hydrogen in galaxies or to view protuberances on the Sun. When was the H-alpha emission of astronomical objects such as galaxies first ...
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How long was the HST initially supposed to work?
For space missions, there is typically a minimum time that is defined for the mission to fulfill all of its science objectives, then an extended mission with extra objectives. And after that, the ...
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Why is the FLRW universe (general relativity solution(s)) sometimes called the 'FRW universe'?
Why is the letter L for Georges LeMaîtres often, or even usually, left out?
Does he, or does he not, deserve some credit for this cosmological solution to Einstein's general relativity?
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Why was there a gap in the number of asteroid detections between 1807 and 1845?
The first asteroid, Ceres, was discovered in 1801, although it wasn't called an asteroid yet. Pallas, Juno and Vesta were discovered shortly after. Then no new asteroids were discovered for 38 years, ...
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Did Cassini return a photo of Saturn's rings shown from closer to Saturn?
A quote from a book, Perelandra by C.S. Lewis: "no eye looked up from beneath on the Ring of Lurga"; now Lurga is Saturn, and no human eye has been to Saturn, let alone at a lower altitude ...
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How did Astronomers mostly(?) agree to publish arXiv preprints along with peer-reviewed Journals? Was there pushback?
This excellent, thorough and well-sourced answer to Has a gravitational microlensing event ever been predicted? If so, has it been observed? includes four links to papers on adsabs.harvard.edu pages, ...
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What is the mnemonic reason behind b being galactic latitude? (in the Galactic Coordinates frame)
I'm not sure if this is a question that has been posted before, and I'm also not sure if the answer is really mnemonic. If that's the case, I'd like to understand why we assigned $b$ to latitude ...
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Was Newton the first to mention the orbital barycenter?
A barycenter is the common center of mass of an orbiting system. Here is a illustrative gif from wikipedia:
The first mention of something like a barycenter that I could find is in a translation of ...
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Equivalence of minor epicycle and eccentric
In epicycle-deferent astronomy, adding a second ”minor” epicycle to account for observational discrepancies is observationally equivalent to shifting the deferent into a so-called eccentric, or a ...
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