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Day 2 Operations with the James Webb Space Telescope is about to begin

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Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#31

Earlier quoted context omitted.

I honestly don't know. Just to clarify, the term "Day-2" isn't from NASA, it's a universal engineering term - which mostly happens on Earth ;) I'm guessing it's just a planning term - like D-Day :shrugs:

* https://dzone.com/articles/defining-day-2-operations * https://about.gitlab.com/solutions/day-2-ops/

Still doesn't explain why "Day" and not "Phase" or "Stage" or "Level" or "Period"

I think I covered the basic explanation in my article as well as dzone and gitlab did in theirs.

:D

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#32
post #14

If this "day 2" does not refer to an actual day (which does not have a real meaning if you're not on a planet), but to a phase, why do they call it "day" and not "phase"? Does "phase" have some kind of negative connotation, does it sound too "scientific"?

I think the terms day 0/1/2 have caught on because they are constant across projects regardless how lacking or overboard the phase planning was. I.e. the project may or may not have much more detailed actual phases and those phases may or may not be obvious to someone without a background in the project but anyone can understand where the project is at without first ingesting the entire project plan.

Funny you would mention days being a constant for a space telescope on an orbit around the sun, where days definitely do not mean the same thing as they do on earth :)

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#34
post #14

If this "day 2" does not refer to an actual day (which does not have a real meaning if you're not on a planet), but to a phase, why do they call it "day" and not "phase"? Does "phase" have some kind of negative connotation, does it sound too "scientific"?

hmm maybe day 2 is after day 1 and before day 3 but not necessarily adjacent, meaning a specific day kicks something off any number of days after a previous planned day? So over the course of the next month we have 3 special days that kick off different phases.

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#35

Time to see how much damage that micrometeoroid did.

I have several telescopes and I have dropped things in the mirrors quite often. The decrease in quality from a damaged mirror is almost zero. You only lose a tiny part of the total surface. Is not like hubble that had the wrong shape. A tiny speck in the mirror is likely undetectable. Even a bigger one wont affect that much.

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#36
post #30

Time to see how much damage that micrometeoroid did.

Statistically speaking, it's quite concerning that such a large hit has occurred so soon after launch and thus does not bode well for the predicted lifespan of the telescope. We pray it was an extreme outlier.

[deleted]

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#37

Earlier quoted context omitted.

* https://dzone.com/articles/defining-day-2-operations * https://about.gitlab.com/solutions/day-2-ops/

Still doesn't explain why "Day" and not "Phase" or "Stage" or "Level" or "Period" I think I covered the basic explanation in my article as well as dzone and gitlab did in theirs. :D

I think "day one" was an existing phrase that was confusingly extended to cover other "start of phase" concepts.

Sounds like a nice way to trick your management though, "Uh no, it won't have feature X on day one, but that will be working by Day-2."

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#38

Time to see how much damage that micrometeoroid did.

A man fired multiple bullets into a telescope and put many holes in the primary mirror, but the science capabilities were only minimally affected: https://en.wikipedia.org/wiki/Harlan_J._Smith_Telescope

This telescope design already has a giant hole in the middle, and the light-collecting capabilities are hardly affected by small holes.

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#39

Earlier quoted context omitted.

I honestly don't know. Just to clarify, the term "Day-2" isn't from NASA, it's a universal engineering term - which mostly happens on Earth ;) I'm guessing it's just a planning term - like D-Day :shrugs:

* https://dzone.com/articles/defining-day-2-operations * https://about.gitlab.com/solutions/day-2-ops/

I'll admit I've never heard of day 0/1/2 before.

Re: Day 2 Operations with the James Webb Space Telescope is about to begin

#40

Time to see how much damage that micrometeoroid did.

A man fired multiple bullets into a telescope and put many holes in the primary mirror, but the science capabilities were only minimally affected: https://en.wikipedia.org/wiki/Harlan_J._Smith_Telescope This telescope design already has a giant hole in the middle, and the light-collecting capabilities are hardly affected by small holes.

I think it's kind of like how FaceID or TouchID work regardless of orientation of face/fingerprint. Or how locating a radio source from data across multiple detectors would utilize math and any damage would drop out as slightly more noise. Modern cameras often have dead pixels in their detectors but they're just skipped in the output photos.
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