Questions tagged [terminology]
Questions regarding specific terms, names, or naming conventions.
102
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Is Sofia a radio telescope proper?
I usually think of SOFIA, the Stratospheric Observatory for Infrared Astronomy as an infrared optical telescope:
SOFIA uses a 2.5 m (8.2 ft) reflector telescope, which has an oversized, 2.7 m (8.9 ft)...
2
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0answers
43 views
How can the CMB have a “monopole anisotropy”?
Wikipedia's Cosmic Microwave Background (CMBR) radiation monopole anisotropy (ℓ = 0) says
When ℓ = 0, the ${\displaystyle Y(\theta ,\varphi )}{\displaystyle Y(\theta ,\varphi )}$ term reduced to 1, ...
4
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1answer
616 views
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 ...
4
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2answers
98 views
How are image credits expressed in Astronomy presentations?
Sorry if this is a stupid question. I'm preparing an astronomy presentation, and I want to make sure I give credits where credits are due. But I see credits appear in different formats, for example:
...
6
votes
2answers
144 views
What is the antonym of “closest approach”?
The distance from Earth to Mars, during their closest approach, is about 55 million kilometers.
At their furthest apart, that distance would be about 401 million kilometers.
Distance
at closest ...
0
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1answer
86 views
Defining a nautical mile
Astronomy is new to me so my question might be stupid: I read that a nautical mile is defined as one minute of latitude along any line of longitude. What if it was the other way round, i.e. one minute ...
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0answers
47 views
Are there actual asteroids in the Oort cloud?
This answer to At what annual rate are new exoplanets being recognized? How does it compare to new asteroids? shows that the rate of new asteroid discovery is roughly two orders of magnitude higher ...
3
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1answer
25 views
Timing based on upper or lower part of sun/moon
When you time an astronomical event, such as the moon/sun rising above the horizon, do you note the time when the the first sliver breeches the horizon or when the bottom of the moon/sun just becomes ...
4
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1answer
190 views
How many solar system objects that can really qualify as a KBO are likely to enter Pluto's Hill sphere each day?
A comment below Which celestial body is able to come closest to Pluto? says that
Technically, many, many small Kuiper belt objects enter Pluto's Hill Sphere (or sphere of influence SOI) every day.
...
2
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2answers
128 views
How does one go about submitting a name for a newly-discovered lunar crater?
Suppose I discover an uncatalogued crater on the lunar surface, and decide to name it. How would I submit my proposed name to the IAU?
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38 views
How does one go about naming a lunar crater? [duplicate]
Suppose I discover an uncatalogued crater on the lunar surface, and decide to name it. How would I submit my proposed name to the IAU?
3
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1answer
90 views
What happened to the 2017 proposal on redefining planethood? Is this information available?
In 2017, Alan Stern et al. submitted a geophysical planet definition to the IAU for review which states
“A planet is a sub-stellar mass body that has never undergone nuclear fusion and that has ...
1
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1answer
65 views
Launch windows for Venus transit; how to convert heliocentric longitudes to date?
Being a bit familiar with celestial mechanics, I know that the Hohmann transfer orbit is the quickest way to transfer between two circular orbits of different radii around a central body in the same ...
5
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1answer
51 views
Does “spectral type” and “stellar classification” refer to the same thing?
Should the tags stellar-classification and spectral-type be merged? has been asked in meta two weeks ago. It requires some careful consideration but so far no response has been forthcoming, so I'm ...
6
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3answers
950 views
“Periapsis” or “Periastron”?
I was taught from Bate Mueller and White, that the proper terms for the closest and furthest points and distances from a body in orbit around another unspecified body are "periapsis" and &...
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8answers
10k views
Do our sun and moon have names?
We seem to have named every moon orbiting other planets. Why haven't we named our own moon? And for that matter, why doesn't our sun have a name since we name or number stars?
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0answers
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Are falling evaporating bodies (FEBs) and exocomets the same thing? How does one know they're falling and evaporating?
Looking for a (short) list of comets with heliocentric escape velocity I stumbled upon Wikipedia's exocoments which like exoplanets, are bound to other stars. I should have been looking for "...
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1answer
169 views
What exactly is a Hamiltonian telescope? Is this one?
This comment on the current answer to Why is this telescope so short? How hard is it to make such a fast primary? says
In this forum topic Borisov appears to call it an f/1.5 Hamiltonian.
Wikipedia'...
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1answer
70 views
Does the Honey moon have a precession problem?
In Steven Colbert's interview with Neil deGrasse Tyson after about 03:16 the following is explained:
But wait, all the moons - all the full moons of the year have ...
16
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3answers
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What are “non-Keplerian” orbits? What are some familiar examples in our solar system, and can some still be closed?
This excellent answer to Forms of stellar orbits around the galactic center invokes the following concepts:
non-Keplerian orbits
closed orbits
I have a fairly good idea what these mean and so might ...
1
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1answer
41 views
Is there an antonym for 'transit', i.e. the transit of a celestial body through the meridian
I'm writing software to calculate the rising, transit, and setting of a body on the celestial sphere for a specific location and date. It seems to me that the opposite of transit, at least in the case ...
4
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1answer
79 views
What exactly are “H30α and He30α images”? (ALMA)
I ran across this paper's title η Carinae: high angular resolution continuum, H30α and He30α ALMA images (arXiv) and see that the body of the paper also mentions "H40α, H30α and H29α".
What ...
26
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1answer
4k views
Is lithium considered a metal in astronomy?
My lecture notes are conflicting on this issue so I seek definitive clarification. In Astronomy, are metals either
A: the elements which form within stars (i.e., not Big Bang nucleosynthesis, where ...
2
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2answers
99 views
Can a pulsar also be a magnetar?
I know this is a simplistic question, but I cannot find a straight answer...
Also, is it possible most or all neutron stars are magnetars and/or pulsars? It's just hard to see all of their properties ...
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0answers
21 views
Are the terms “PG 1159 star” and “pre-white dwarf” synonymous?
Are the terms "pre-white dwarf" (as in Gies et al. 2020, "Spectroscopic Detection of the Pre-White Dwarf Companion of Regulus") and "PG 1159 star" (as described, e.g. in ...
9
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1answer
718 views
What do the words “p-type” and “s-type” mean?
As explained in various sources (such as that answer), a planet in an s-type orbit orbits one of the stars of a binary star system, whereas a planet in a p-type orbit orbits both stars. A synonym for ...
6
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1answer
158 views
Clarification of radio spectrum terminology
For a radio spectrum, when is it called thermal emission, synchrotron emission, self-absorbed synchrotron emission and inverted spectrum? They are all power-law and their difference is power-law index?...
7
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2answers
348 views
What does “additive fringing from the (multiplicative) twilights” mean?
The question How can I make the fringing pattern visible in my flat (twilight) images for filter i? includes:
I have a bunch of twilight flats that have been preprocessed (dark, bias, overscan etc.)...
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0answers
65 views
Why is the Nancy Grace Roman Space Telescope (WFIRST) coronagraph considered “beyond-state-of-the-art”?
After about 01:30 in the NASA video NASA's Nancy Grace Roman Space Telescope: Broadening Our Cosmic Horizons the narrator says:
To deepen its study of exoplanets ...
4
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1answer
117 views
When was Hubble tension first noticed? When was this term first used?
When was Hubble tension first noticed? When was this term first used? Who used this term for the first time?
2
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0answers
95 views
Why are helium resonance lines called “resonance lines”?
Examples of the use of the term:
Formation of the helium extreme-UV resonance lines
On the Formation of the Resonance Lines of Helium in the Sun (unpaywalled)
Formation of the helium EUV resonance ...
2
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1answer
169 views
Do Astronomers really never call Lagrangian points “libration points”?
In this answer to Who called the Lagrangian points as “Libration” points and and why was the terminology “Libration” used? I described my feeling that Lagrangian points were also sometimes called &...
4
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1answer
124 views
Astronomical Term *Mezzocielo*
What is the name of the point of intersection of the great circle passing through the celestial north pole P and the Zenith Z, with the celestial equator? (Point T in the figure)
In Italian this point ...
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1answer
84 views
What exactly is a “conclusive association” in Astronomy?
Phys.org's Astronomers use slime mold model to reveal dark threads of the cosmic web says
A computational approach inspired by the growth patterns of a bright yellow slime mold has enabled a team of ...
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0answers
77 views
What is the opposite of the vernal point?
The equator and the ecliptic cross at two nodes. One of those nodes is the vernal point. What is the other one called?
5
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1answer
172 views
Is there a distinction between NEOs and near-Earth asteroids? Is there a difference?
My "real question" is in Space Exploration Meta (neo (near-earth-object) and near-earth-asteroid tags, do we need both?), but I think that astronomers will be able to help understand the situation and ...
2
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0answers
77 views
When we say a variable star is “fainting” does it mean something more or different than “dimming” or “fading”?
A comment below the question Does the current “fainting” of Betelgeuse show any spectral trends that differ from it's normal variability? suggests that "dimming" would be a better term, but I have a ...
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1answer
47 views
Is there a general term used to identify the high flat features within Noctis Labyrinthus on Mars?
At the western end of Valles Marineris, where it mets Noctis Labyrinthus (highlighted section of image)
there are a series of flat geological formations between the canyons.
Is there a unique term ...
6
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1answer
154 views
What are other names for planetoids that aren't orbiting a solar system, but hurtling through space?
I'm trying to think of a good word for an asteroid/planetoid that has no stable orbit but has been ejected from a system and is passing close to a sun. Any help?
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1answer
90 views
What do you call it when a satellite goes once around its planet?
When a planet or a satellite turns around itself, its called a rotation. When a planet goes once around the Sun, it's called a revolution. What do you call it when a satellite goes once around its ...
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0answers
70 views
What is an “Off Rowland-circle Telescope”?
The NASA Goddard news item NASA to Demonstrate New Star-Watching Technology with Thousands of Tiny Shutters says:
The technology, called the Next-Generation Microshutter Array (NGMSA), will fly for ...
0
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1answer
880 views
Is intrastellar commonly used by astronomers to refer to objects within our solar system?
The CNET article Interstellar comet Borisov looks ordinary, making Oumuamua even weirder says:
A paper published Monday in Nature Astronomy lays out the early data on Borisov, which is just the ...
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2answers
470 views
Does astro means space or stars [closed]
In the popular TV show The Big Bang Theory Season 3, Episode 4, Sheldon Cooper said that astro means star and Raj said astro means space, I got a little confused here, various websites and others are ...
1
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1answer
150 views
Origins and most frequently used; perinigricon vs peribothron?
Gizmodo.com's Astronomers Spot Unprecedented Flashes From Our Galaxy's Black Hole mentions Sgr A*'s companion gas cloud G2 and that Wikipedia article uses the term perinigricon, but that mentions ...
4
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1answer
380 views
Sorting out Julian Day, Julian Date, Julian Day number, Julian Day Calendar, and Julian Day Table
In this answer I mention day number which is 1 on the first day of each calendar year (January 1) and increments to 365 or 366 on December 31 of that year.
There was an edit proposed, which included ...
3
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1answer
781 views
Word for blue ring around the Earth
From certain positions in outer space the Earth will appear to have a blue ring around it when the viewer is in the shadow of the Earth and sunlight is passing through the atmosphere.
Here is a ...
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2answers
81 views
Is there a term for asteroseismology as applied to giant planets?
Giant planets such as Jupiter have oscillations which enable analyses using the techniques of asteroseismology, for example Gaulme et al. (2011) detected global modes on Jupiter via radial velocity ...
21
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2answers
3k views
What is the name of meteoroids which hit Moon, Mars, or pretty much anything that isn’t the Earth?
A meteorite according to the Oxford English Dictionary is
A piece of rock or metal that has fallen to the earth's surface from outer space as a meteor.
But, meteors impact other planets. Are they ...
4
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1answer
112 views
Are there recommendations to use “Hubble-Lemaître constant” instead of “Hubble constant”?
The IAU recommends renaming the Hubble law as the Hubble-Lemaître law, as discussed at its General Assembly in 2018 (see this press release and the links therein).
I have now stumbled upon an ...
2
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2answers
305 views
Adjective for things outside our solar system
I know we have "exoplanets" etc. but those are nouns for specific objects outside our solar system.
We have extraterrestrial for objects outside Earth's atmosphere, but I don't know if we have a ...
