Questions regarding words and abbreviations used in the fields of spaceflight and space exploration, and their meaning when used in those contexts.
Questions tagged [terminology]
206 questions
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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 should not be taken at face value.
How and why,…
Dancrumb
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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 there is an acronym inside of an acronym. Are there…
CourageousPotato
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Is the air "sucked out" or "blown out" into space when the hatch opens?
In a somewhat famous Star Trek: The Next Generation quote Data corrects Riker on the 'correct term' for a scenario where a hatch on a space capsule breaks open and all the crew are killed.
Riker: "You were right. Somebody blew out the hatch. They…
user6587
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Did NASA ever use astronomical symbols for planets?
In 19th century texts on astronomy, the planets are often represented by symbols: ☿ for Mercury, ♀ for Venus, etc..
Did NASA ever use these symbols, or were they already obsolete by then? If they did use them, I'd expect it to be very early on.
Joe
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What is a reference mission?
I've seen the term "reference mission" used in connection with proposed missions to the Moon, Mars, etc..
What exactly is "reference" about a "reference" mission, as opposed to a proposal, plan, or whatever else? What is the objective behind the…
Anthony X
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What term can we use to describe a planet's or dwarf planet's nearest distance to Earth?
Is there a single term that completes this sentence: "at its _____, Pluto is about 27AU from Earth." peri- something...?
bishop
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Why don't I find the concept of cosmic velocities in western space-related materials?
One of my earliest contacts with the concept of orbital mechanics was learning about the four cosmic velocities. They were in my primary school handbook. They were referenced in amateur astronomer's guidebook. They appeared during the university…
SF.
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What do you call an object that has a moon orbiting?
On Earth we call The Moon a moon, but if we were on The Moon what would we call the object we are orbiting around?
If I'm not being very clear I'm looking for a word that would describe what Earth to The Moon, Pluto to Charon, and Dactyl to Ida.
Jimmy
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French terminology for the space industry
I am interested to know if there is some consolidated resource for matching space and satellite terminology between English and French.
Examples of words to translate include: Orbital Elements, Space Weather, Satellite Operations, Uplink / Downlink,…
Manny
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Is there a canonical definition of the term "block" as used in "Falcon 9 block 5"?
I gather this has a meaning related to "version". However, I have seen this term used for military and commercial aircraft and other products (generally connected to government or aerospace).
I am looking for a formal definition of the term (not…
martin's
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What is range angle?
In several papers on powered explicit guidance, I've come across the term "range angle." I'm familiar with inclination and azimuth angles, but range angle is new to me.
A quick search gave no clear answers to what this might mean. I know the info is…
user36480
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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-major axis, ... I mean that that perigee is not…
Cristiano
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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 Friendship 7 Mercury heat shield detachable?
How do…
DrSheldon
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