Linked Questions

13 votes
1 answer
2k views

Why is the sunny side of JWST's sunshield purple and covered with silicon?

After about 08:52 in Destin's Smarter Every Day's Why Are there Holes in the James Webb Sunshield? (Explained by My Dad) - Smarter Every Day 270 (linked below) ...
uhoh's user avatar
  • 149k
13 votes
2 answers
2k views

Did New Horizons also demonstrate the "Pioneer Anomaly"?

In this short but very helpful answer @MikeH provides a link to this short item published in Nature:"...and farewell to the Pioneer Anomaly" which is well worth reading! It references a ...
uhoh's user avatar
  • 149k
10 votes
2 answers
369 views

Can any other telescopes see the James Webb Space Telescope?

The James Webb Space Telescope has no cameras mounted that look at itself. If a malfunction occurred on-board, would any other telescope be able to resolve it with sufficient clarity to provide useful ...
DrMcCleod's user avatar
  • 700
8 votes
1 answer
598 views

How can stellar images be "subtracted" from a sequence of exposures? (difference imaging)

The press release UH ATLAS telescope discovers first-of-its-kind asteroid from the Institute of Astronomy at the University of Hawaii shows an image of an "active asteroid" among a field of stars. ...
uhoh's user avatar
  • 149k
4 votes
2 answers
585 views

Will the Artemis Gateway Lunar Space Station be visible from Earth by amateur observers?

When the entire Lunar Gateway space station is built it would be a bit smaller than the ISS. We amateur astronomers and observers love to spot the ISS and be able to follow the history of space ...
Swike's user avatar
  • 2,501
9 votes
1 answer
1k views

What would JWST's apparent magnitude be?

I understand that for any viewer, JWST would roughly occupy the anti solar spot in the sky. Size of and distance to the spacecraft is known, and its reflectivity (of the sunshield) is probably known. ...
Willie's user avatar
  • 91
12 votes
1 answer
346 views

Could you bounce a tennis ball off of the James Webb sunshield?

News articles keep referring to the James Webb Space Telescope's sunshield as "about the size of a tennis court", which raises the question: could it function as a tennis court? Or, more ...
Jeremy Friesner's user avatar
5 votes
1 answer
400 views

What goes into an Iridium Flare prediction model besides the ephemerides?

Empirical Answer Considered! (see the end of the question for details) Iridium satellite flares are a class of Satellite Flares that originate from satellites in the current Iridium constellation. ...
uhoh's user avatar
  • 149k
2 votes
1 answer
309 views

What would the James Webb telescope see if it looked at itself from Earth?

This question asks whether any ground-based telescopes can see the James Webb. The answer ("yes, but it's basically just an indistinct dot") is deeply underwhelming. If only we had a much ...
Richard's user avatar
  • 792
2 votes
0 answers
129 views

Predicting non-Iridium flares and Why NOSS satellites flare?

I just saw two point-like sources flaring in the sky in perfect sync. It was spectacular and a big surprise to me. The full event lasted at most 4 seconds. My position is in the Usera district in the ...
Swike's user avatar
  • 2,501