Questions tagged [terminology]

Questions regarding words and abbreviations used in the fields of spaceflight and space exploration, and their meaning when used in those contexts.

Filter by
Sorted by
Tagged with
3
votes
1answer
83 views

What is the equivalent of Curiosity's “MSL” in the context of Perseverance? What's the official name of the mission? Are the distinctions similar?

Answers to Where does MSL end and Curiosity begin? explain the difference. There was much fanfare for the naming contest for the Perseverance rover, but I don't know what the mission is called. ...
20
votes
4answers
3k views

Do scientist who study martian geology typically use the term areology?

In the book Red Mars by Kim Stanley Robinson, I came across the word "areology". Is this word often used in scientific publications, or is it a term limited to the scope of science-fiction, ...
1
vote
2answers
149 views

What is “TFR” in the context of operating a marine radar on top of a “water tower” at a launch site?

This answer to What is this propellor-like object on top of the SpaceX Hopper? includes the following: FCC filing: Space Exploration Technologies Corp. 0459-EX-CN-2020: ...d) List any natural ...
13
votes
7answers
3k views

How does time work on other planets?

I’m a game developer making a space-based game. I want to implement a system where the time is different depending on the planet. I think this would work like time zones, but to be honest, I’m not ...
3
votes
2answers
80 views

Is there a term that references the time delay between two objects communicating in space, especially at great distances?

When communicating at distance in space (such as Earth communicating to a craft orbiting Mars), the communication experiences a time delay. My research indicates this delay maybe called "One-Way Light ...
2
votes
2answers
83 views

Who called the Lagrangian points as “Libration” points and and why was the terminology “Libration” used?

I am curious about the naming and why were the equilibrium solutions of the CR3BP called as Libration points? Who called them that and what is the history behind it?
7
votes
0answers
124 views

Why do Russian rocket engineers call C₂H₈N₂ “heptyl”?

Unsymmetrical dimethlyhydrazine or "UDMH" is a propellant which has been used by Russian, American, European, Chinese, and Indian rockets. Russian rocket engineers nickname it "heptyl". Why was this ...
2
votes
1answer
115 views

Is “liftoff mass” = “ignition mass”?

The answer to How much propellant is used up until liftoff? makes me wonder whether the terms "ignition mass" and "liftoff mass" have widely accepted precise meanings. Does anybody have an ...
0
votes
1answer
122 views

Does the elliptical orbit have many periapsis points?

If I have the position and velocity vectors of a satellite in an elliptical orbit for one point in time, then I can know its position in its orbit at any other time, and with that I can calculate the ...
2
votes
1answer
122 views

Is there an alternate term to “fired” for the Reaction Control System?

Do the astronauts use any word, other than "fired" when referring to the use of the Reaction Control System for attitude control or translation?
24
votes
3answers
4k views

What is the story behind specific impulse being expressed in seconds?

I've heard a couple of explanations but none of them quite make sense. One was that the German rocket engineers used metric and the American rocket engineers used the English system and seconds were ...
1
vote
0answers
85 views

What terminology is used to describe spacecraft in stationkeeping?

Forgive any inaccurate wording of this question. If a Soyuz craft which had been docked at the Zvezda module backed away from the ISS and remained at stationkeeping, would NASA, Roscosmos, or the ESA ...
1
vote
0answers
108 views

Official terminology for non osculating orbital elements

When I need to talk about an orbital element that is not osculating and that it is the true/actual element at a given instant, I use the term "actual": actual perigee, actual eccentricity, actual semi-...
3
votes
0answers
57 views

What is the proper terminology for the process of a satellite entering a planet's shadow? [closed]

What is the proper terminology for when a satellite or spaceship passes into a planet's shadow or night side? Is it crossing the terminator? Passing into eclipse (or something better)? If there is a ...
2
votes
0answers
71 views

Does NASA use any of the twilight designations?

Do the differences in civilian, nautical, and astronomical twilight have any technical relevance to NASA either on Earth or any other object in the solar system where a probe has landed? Does NASA ...
3
votes
1answer
150 views

NASA's definition of a launch vehicle

Does NASA's use of the term launch vehicle apply only to those that ascend from the Earth's surface and leave the atmosphere? If so why is the term limited that way?
1
vote
3answers
293 views

When is a rocket a rocket?

A comment was offered in this question, how technically soft landing works without air on the moon?, asking "what do you mean by 'rocket'." This brought to mind the question of what is a rocket. Does ...
6
votes
1answer
240 views

What (the heck) are “space-fixed coordinates” as described in Apollo mission trajectory analyses?

@Ludo's answer to If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for? shows the table and its source shown ...
2
votes
1answer
164 views

What do these Apollo era terms mean?

@Ludo's answer to If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for? links to Apollo Mission 11, ...
25
votes
4answers
4k views

Name for geostationary orbit around another planet

A geostationary orbit is a circular orbit in Earth's equatorial plane whose rotation period matches that of the Earth. The "geo" in "geostationary" means Earth, so is there another term to designate ...
1
vote
1answer
79 views

Definition of a trans-Earth injection

Should every "propulsion maneuver used to set a spacecraft on a trajectory which will intersect the Earth's Sphere of influence" be called a trans-Earth injection? Regardless where the spacecraft ...
6
votes
0answers
713 views

What is the difference between a “Suicide burn” and a “Hoverslam”?

As far as I can tell, the terms Suicide burn and Hoverslam have both been invented rather recently (with SpaceX themselves coining Hoverslam and the Kerbal Space Program loosely credited with Suicide ...
2
votes
1answer
247 views

Orbital vocabulary confusion! How can the tangential velocity of an elliptical Kepler orbit not be tangent to the orbit?

I'm now officially confused about the usage of "tangential" when breaking down orbital velocity components. It started with edits and comments on this answer to Orbital speed is (vector) sum of ...
1
vote
1answer
57 views

What is the Azimuth plane and how did it originate?

Background: As I understand it, "up" and "down" navigation aboard the ISS are referred to as Nadir and Zenith with down (towards Earth) being Nadir ...
5
votes
1answer
181 views

Term used to identify the blue bars/rails in the ISS?

The interior of the ISS is filled with blue bars used by astronauts to secure their feet and remain in one place. Does NASA have a term for these?
5
votes
2answers
546 views

What is the difference between an engine skirt and an engine nozzle?

I have seen "engine skirt" and "engine nozzle" both used for the bell-shaped end of a rocket engine. Is there a difference?
27
votes
5answers
5k views

Are there any “Third Order” acronyms used in space exploration?

On a recent episode of the Planetary Radio podcast, the topic of Third-Order Acronyms was brought up. At NASA, there are many Second-order acronyms like SAFER - Simplified Aid For EVA Rescue, where ...
0
votes
1answer
244 views

What exactly is an F-mission?

This @CometInterceptor tweet shows the mission's insignia. The complete wording on the patch is as follows: COMET INTERCEPTOR F-mission Question: What exactly is an F-mission? See also: Comet ...
2
votes
0answers
141 views

Is “Space Shuttle” written as a proper noun in the spaceflight industry?

Writing the question Was a real Space Shuttle ever used as a really big simulator? (and several others) I capitalize Space Shuttle because as far as I know, that's the actual name of NASA's spacecraft,...
9
votes
1answer
2k views

What is and what isn't ullage in rocket science?

This comment and others below this answer address ullage. "Ullage" basically just means "the portion of the tank that isn't filled with liquid". The extended rocket-science implications of ullage ...
44
votes
2answers
8k views

Why do space operations use “nominal” to mean “working correctly”?

In common parlance, "nominal" means "in name only", "small (amount or quantity)" or "stated, but not necessarily reflective of reality". So, the general sense is that "nominal" means something that ...
0
votes
1answer
66 views

Usage of “weight-to-thrust” instead of “thrust-to-weight”

Section 4.1.5 of the Apollo Program Summary Report states The major design criteria for the Saturn I were: a. Minimum vehicle lift-off weight to thrust ratio I've usually seen the reverse ...
1
vote
1answer
126 views

Gravitational keyhole for spacecraft flyby?

Is there a term for the area near a planet a spacecraft must pass through for a gravitational-assist flyby, or does 'gravitational keyhole' apply to gravitational assists as well as for asteroids?
7
votes
1answer
335 views

Did NASA distinguish between the space shuttle cockpit and flight deck?

NASA used both terms on their website, Cockpit and Flight Deck. One answer on Aviation SE Cockpit vs Flight Deck?says there is a difference between the two. Did NASA use the terms interchangeably, ...
0
votes
2answers
121 views

What is the distinction between detaching, jettisoning, and dumping?

What is the difference between the terms detach, jettison, and dump? Related Aviation.SE question: https://aviation.stackexchange.com/q/22903 Examples of using the term "detach": Why was the ...
1
vote
1answer
214 views

How often did launch vehicles have a “Stage 0”, and what does it mean exactly?

While trying to do some reading for the question Need help understanding staging shown in infographic of Titan launch of Hexagon satellites I ran across the Wikipedia article for Titan III. This ...
3
votes
1answer
187 views

Is the term 'lead head' used by astronauts?

In an article on the Space.com website, the author states "Very few astronauts have what's called the 'lead head'--immune from space adaptation syndrome or space sickness." I couldn't find any other ...
6
votes
1answer
128 views

What's the point/area of space called where there is equilibrium between 2+ different gravitational forces?

For some reason I want to call it a 'gravity well' but I know that a gravity well is just the gravitational force distribution in space due to an object with mass. But regarding my question, isn't ...
0
votes
1answer
78 views

GLOM of a launch vehicle

What do you mean by GLOM of a launch vehicle? When I googled about it, it says it is a type of mass but I am unclear about it.
2
votes
1answer
72 views

List of words and abbreviations like A-OK and MAG

Is there a list of casual, non-technical words, phrases, abbreviations and the like that have developed in any of the space agencies around the world?
1
vote
0answers
136 views

Is there a term for the activity of weightless astronauts hanging out on walls or ceilings?

Weightless astronauts often sit, stand, walk, or sleep on (or near) surfaces that (with gravity) we would normally call walls or ceilings. I reference such a phenomenon in my comment here: I would ...
7
votes
3answers
2k views

Why “strap-on” boosters, and how do other people say it?

This came up for me in the context of translating something into German. Everybody throws around terms like "strap-on boosters", although they aren't actually held on by straps. It's not even meant ...
6
votes
1answer
388 views

Did NASA have a term for the “sky” during the Apollo missions

Did NASA have a distinct word to describe what the Apollo astronauts saw when they looked at out at the stars, when traveling between the Earth and the Moon? Sky does not seem right, as that word ...
1
vote
4answers
157 views

Is GEO redundant (Geo- and Earth)? Would we call a Lunasychronous Lunar orbit LLO?

I think the title of the question Is it possible to establish a synchronous lunar orbit without using Lagrange points? is absolutely clear; it's an orbit around the Moon that is synchronous to the ...
3
votes
2answers
448 views

What is meant by “a high-energy geostationary orbit”? (SpaceX Arabsat 6A)

The Teslarati article SpaceX’s April 7th Falcon Heavy launch a step toward new commercial markets says: While there is some inherent uncertainty surrounding the (once again) fairly new rocket, ...
4
votes
3answers
1k views

When was the first strap-on booster used in spaceflight?

The first use of the term "strap-on" in Google Ngram viewer is in 1930 and presumably that wasn't about a booster being attached to a rocket for additional thrust at lift-off. When was a strap-on ...
2
votes
2answers
215 views

Terminology dispute: is an orbital flight still a ballistic flight?

We have a terminology dispute with a colleague: could a flight by elliptical orbit trajectory be called a ballistic flight as well or limits of the later is a parabolic trajectory of a suborbital ...
1
vote
1answer
128 views

What is SpaceX's “rocket canister”?

The CNBC News item SpaceX, Boeing design risks threaten new delays for US space program says: Just ahead of the first scheduled un-manned test flight slated for March 2 under NASA's multibillion-...
12
votes
1answer
879 views

Opportunity's last tau was 10.8; what does that mean and how is tau defined and measured?

@ahiijny added a direct link to the Sol 5110-5114 MER B Downlink Report. These are the final days that signals were received from Opportunity. The message "Tau Value is NOT a Typographical Error" ...
5
votes
2answers
114 views

Can “space weather” refer to deep space environments or only to Earth's (or another planet's) upper atmosphere?

@OscarLanzi's interesting answer and my comment there led me to read Wikipedia's article Space weather. The article exclusively seems to only talk about effects in Earth's upper atmosphere; the only ...