So far so good
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John Clark
Dec 25, 2021, 8:31:19 AM12/25/21
to 'Brent Meeker' via Everything List
I hope everybody on the list is having a Merry Christmas. I'm having a very Merry Newtonmass myself because I just watched the launch of the wonderful James Webb telescope on TV and so far, at least on the branch of the multiverse that I'm on, everything seems to be going OK. But I'm gonna keep my fingers crossed for the next 29 days.
John K Clark See what's on my new list at Extropolis
wex
Lawrence Crowell
Dec 26, 2021, 6:53:51 AM12/26/21
to Everything List
The James Webb Space Telescope is on its way. There is now a 2 week period of angst where some 344 critical motions have to take place. The spacecraft must unfold as an origami piece successfully and anything that snags this up could be a critical failure.
The JWST will set itself at the Lagrange L2 point, or really a loop. The orbit of the moon perturbs the L2 point into a cycle. A sound out should be given to the unsung classical mechanics people who worked this out. Having worked on spacecraft geodesy I know this is not easy work.
The JWST will look in the infrared from 0.6μm, the orange-red visible spectrum out to 28.3 μm. The reason is that the earliest galaxies are redshifted due to the expansion of space or Hubble expansion. This expansion in a linear approximation predicts a velocity of recession v = Hd, for H = 72km/sec-Mpc. Mpc = million parsecs, for a parsec (parallax second = distance out to where Earth's orbit gives a 1 second parallax) equal to around 3.26 light years. For the velocity a galaxy v = c, remember it is space that frame dragging galaxies and not special relavity motion we have z = 1. Currently galaxies out to around z = 8 are studied. but there is a lot of astrophysics out further with higher z unexplored. At 28.3 μm sources of light emitted with z around 30 could be explored.
Contrary to what a lot is said, this is not the earliest moments of universe we have explored. It is a gap between the cosmic microwave background (CMB) with z = 1100 and current observations with z at most 10 or so. The JWST will fill in an observational gap.
The astrophysics of interest is the origin of galaxies and the first stars, or PopIII stars. Also of interest is how these early structures correlate with the anisotropy in the CMB.
We have two weeks of angst here, so hold on.
The JWST will set itself at the Lagrange L2 point, or really a loop. The orbit of the moon perturbs the L2 point into a cycle. A sound out should be given to the unsung classical mechanics people who worked this out. Having worked on spacecraft geodesy I know this is not easy work.
The JWST will look in the infrared from 0.6μm, the orange-red visible spectrum out to 28.3 μm. The reason is that the earliest galaxies are redshifted due to the expansion of space or Hubble expansion. This expansion in a linear approximation predicts a velocity of recession v = Hd, for H = 72km/sec-Mpc. Mpc = million parsecs, for a parsec (parallax second = distance out to where Earth's orbit gives a 1 second parallax) equal to around 3.26 light years. For the velocity a galaxy v = c, remember it is space that frame dragging galaxies and not special relavity motion we have z = 1. Currently galaxies out to around z = 8 are studied. but there is a lot of astrophysics out further with higher z unexplored. At 28.3 μm sources of light emitted with z around 30 could be explored.
Contrary to what a lot is said, this is not the earliest moments of universe we have explored. It is a gap between the cosmic microwave background (CMB) with z = 1100 and current observations with z at most 10 or so. The JWST will fill in an observational gap.
The astrophysics of interest is the origin of galaxies and the first stars, or PopIII stars. Also of interest is how these early structures correlate with the anisotropy in the CMB.
We have two weeks of angst here, so hold on.
LC
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