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JWST Just Passed Line 100K Miles From L2
NASA ^ | 15 January 2022 | Steely Tom

Posted on 01/15/2022 7:42:56 PM PST by Steely Tom

JWST is now less than 100K miles from it's L2 destination.

Its current speed is 0.1731 miles per second, or about 623 mph. This speed is slowly decreasing as it approaches its equilibrium distance from Earth. It will take another eight days to close the remaining distance to its destination; the first 798,000 miles has been traveled in 21 days, 15 hours.

JWST cold side is at -200°C, only 73° above absolute zero.


TOPICS: Astronomy; Science
KEYWORDS: jwst
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To: Steely Tom

I wonder if they will get a clear photo of Uranus? (Sorry. Even at age 71, I’m 12 at heart)


21 posted on 01/15/2022 9:01:09 PM PST by llevrok (Pronouns: Me/myself/& I)
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To: telescope115
It’s just amazing to me how astronomers from 2-300 years ago were able to work all this out in the first place

Leibnitz/Newton

22 posted on 01/15/2022 9:20:26 PM PST by Bobalu (Lord, keep your arm around my shoulder and your hand over my mouth...)
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To: Nifster

House calls for repairs won’t be happening this decade.


23 posted on 01/15/2022 9:24:25 PM PST by Vermont Lt
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To: Bobalu
Leibnitz vs. Newton was (to me anyway) a little like Apple vs. Microsoft.

Leibnitz was open about his discoveries with respect to Calculus, and his notation was easier to understand and to use.

Newton kept his work a secret, not wanting to reveal it until he had developed it to the fullest possible extent. Also his notation was more esoteric and obscure.

Leibnitz was an "open system," Newton was a "closed system."

24 posted on 01/15/2022 9:27:59 PM PST by Steely Tom ([Voter Fraud] == [Civil War])
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To: telescope115

My favorite scene from Apollo 13 was when they were coming back to Earth and they needed to make a course correction prior to re-entry and all the scientists at the Space Center whipped out there slide rules and started working on the calculation.

It’s kind of amazing that for the most part we went to the Moon using slide rulers to get the math right.


25 posted on 01/15/2022 9:31:09 PM PST by Clutch Martin (The trouble ain't that there is too many fools, but that the lightning ain't distributed right.)
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To: Steely Tom

Webb has slowed down to a bit over 600 mph, really slow for space travel stuff.

Looks like a very precise job getting it there without skidding past and burning out the brakes. /s


26 posted on 01/15/2022 9:31:31 PM PST by doorgunner69 (Let's go Brandon)
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To: Steely Tom

Would be great if the pic came back and it showed “I Did All This”


27 posted on 01/15/2022 9:35:47 PM PST by Secret Agent Man (Gone Galt; not averse to Going Bronson.)
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To: crazy scenario

And African-American ones.😏


28 posted on 01/15/2022 9:42:00 PM PST by BiteYourSelf ( Earth first we'll strip mine the other planets later.)
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To: Secret Agent Man
Would be great if the pic came back and it showed “I Did All This”

I think a fair number of extremely prominent particle physicists and cosmologists have come to believe that that's what the deep structure of the universe is telling us. There are just too many parameters that have to be exactly what they are, or else the whole thing collapses in a reverse Big Bang, or simply evaporates into nothing in a few nanoseconds.

The precise value of the "fine structure constant" is one such parameter, but not the only one.

29 posted on 01/15/2022 9:48:48 PM PST by Steely Tom ([Voter Fraud] == [Civil War])
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To: Steely Tom

For those who don’t get it: L2 is a LaGrange point, a point in space where an object will keep a stable orbit at a constant relationship to a distant object at a different point in that orbit.

For instance, there is a point where an object would stay at exactly the opposite side of the Sun from the Earth. (This is why there was conjecture that there could be a mysterious object on the opposite side of the Sun and we’d never know it... until the era of interplanetary spaceships.) There are also points only 60 degrees away from the Earth. And there are points, incredibly, in front of the Earth and behind it, where an object will simply stay, without revolving around the Earth! L2 is one of those.


30 posted on 01/15/2022 9:54:12 PM PST by dangus
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To: Steely Tom

I like that bowling ball analogy.


31 posted on 01/15/2022 9:56:31 PM PST by ProtectOurFreedom (81 million votes...and NOT ONE "Build Back Better" hat)
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To: Steely Tom

speed relatve to what? Because it’s traveling arpund the sun a lot faster. It’s travelling around the galactic center even faster and so on...


32 posted on 01/15/2022 10:21:43 PM PST by Theophilus (Thes so-called "vaccines" are the top three comorbidities)
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To: Steely Tom
28 microns is the peak wavelength emitted by a black body at 105°K, or -270°F. This corresponds to extremely old, red-shifted light.

Help me out here (you are obviously very up-to-date on your Cosmology - at least in comparison to me).

The current black-body temperature (temperature inferred from the frequency of the cosmic background radiation) is 2.7 Kelvin (note the lack of a "degree" sign), yes? And it is dropping geometrically? So, when the universe was half as old, the temperature was 5.4 Kelvin? When it was a quarter of its current age, the temperature was 10.8 K, and so on.

So a temperature of 105 K would mean seeing light from a time when the universe was only about 2% of its present age, correct?

Regards,

33 posted on 01/15/2022 10:27:38 PM PST by alexander_busek (Extraordinary claims require extraordinary evidence.)
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To: Steely Tom
TMA = too many acronyms
34 posted on 01/15/2022 10:35:49 PM PST by McGruff (Trump/DeSantis 2024)
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To: Steely Tom

IMO, even if Newton was first with the Calculus then Leibniz still contributed a great deal by creating a much superior notation.

Amazing how the time for a new idea comes along and somehow touches several people at about the same time..

I believe Claude Shannon was a man of similar brilliance in comparison to Newton and Leibniz...


35 posted on 01/15/2022 10:43:33 PM PST by Bobalu (Lord, keep your arm around my shoulder and your hand over my mouth...)
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To: Theophilus

“...speed relative to what?...”
-
Relative to L2


36 posted on 01/15/2022 10:55:32 PM PST by Repeal The 17th (Get out of the matrix and get a real life.)
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To: Steely Tom

Speed down to 618 mph as I write this.

How close to 0 mph will the cruising speed go before it goes into its halo orbit around the invisible L2 point?

In miles, how large will its L2 orbit be?

In mph, what will its orbital speed be around L2?


37 posted on 01/15/2022 11:28:17 PM PST by zeestephen
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To: Steely Tom

Oh my! They’re using McDLT technology to keep the cold side cold and the hot side hot!


38 posted on 01/15/2022 11:33:34 PM PST by who_would_fardels_bear (This is not a tagline.)
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To: alexander_busek
That's a clever analysis; I don't know enough cosmology to be able to say whether it's true as to reasoning, but your result is pretty accurate. I think they expect JWST to see back to something like 2 or 3% of way back to the Big Bang, although I don't think they're exactly certain of "how far back" they will see.

It seems to me like there's some assumptions you're making in your essentially linear approximation of peak black-body radiation intensity over time that I'm not knowledgeable enough to be able to judge as to validity, but your reasoning don't seem obviously wrong.

Also the resolving power in terms of dynamic range of JWST's image sensors is another issue; it seems to me that that would have a bearing on your theory. I'm not sure that a distant object just a few degrees above the 105°K temperature limit would stand out from the background enough for the JWST sensors to get much of a read on it. I suppose if they integrate light for many weeks or months (like they did for the Hubble Deep Field pictures) they could get enough signal-to-noise ratio to resolve such an object.

39 posted on 01/15/2022 11:36:26 PM PST by Steely Tom ([Voter Fraud] == [Civil War])
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To: zeestephen
How close to 0 mph will the cruising speed go before it goes into its halo orbit around the invisible L2 point?

That's a question I have too. They haven't talked about that as far as I can discover, and I don't know enough about orbital mechanics as it relates to approaching the L2 point to be able to figure the answer out from first principles.

Perhaps they will reveal this in the coming days.

40 posted on 01/15/2022 11:40:01 PM PST by Steely Tom ([Voter Fraud] == [Civil War])
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