James Webb

[popeyespappy]

BIG ladder.

I'm sure most here are familiar with the JWST planned L2 orbit, but a lot of people probably don't understand exactly how far out that really is. At a about a million miles from Earth the JWST will be more than four times further away from the Earth than the moon.

Yes, I know that, like I said... a BIG ladder  

Though that does mean no chance of any service or repair missions... better get it right first time!

Which is why I'm worried about problems. Any number of little failures could cripple or kill it with little to no chance of repair of anything other than software issues.

[HappySkeptic]

There is a campaign to get the telescope renamed.

https://www.nature.com/articles/d41586-021-02010-x

Basically, Webb was a politican during the "lavender scare", and at least one gay scientist was fired from NASA while Webb was administrator, for being gay.

I don't think this effort should succeed, unless it is shown that Webb was an anti-gay instigator.  No-one living before 2000 is going to be "pure enough" for culture activists. Perhaps we can never name anything after former politicians?

That said, a "Carl Sagan Telescope" has a nice ring to it, and pro-marijuana activists will be onboard.

[DocIllinois]

Examinations of space's properties during the Era of Reionization and how it led to the universe's current condition is interesting, as well as the contribution of outflows to the distribution of elements and gas.

[HappySkeptic]

I'm most interested in observations of extra-solar planets. However, even Webb isn't going to be able to see earth-like planets or measure their atmosphere. That will likely require LUVOIR or a set of space-based telescopes doing interferometry.

[Anomalocaris]

I'm most interested in observations of extra-solar planets.  However, even Webb isn't going to be able to see earth-like planets or measure their atmosphere.  That will likely require LUVOIR or a set of space-based telescopes doing interferometry.

depends on what you mean by “see”.   dozens of exoplanets have already been directly imaged from the ground.

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There are also several additional Hubble scale optical snd near optical space telescopes in the works, scheduled to be launched in the next 5 years. They either cover different wave length from hubble, or capable of scanning the sky much more quickly than hubble so as to be able to provide full coverage of the sky at bear hubble resolutions. These are Less flashy than JWST, but perhaps promise work of comparable importance.

[vulcanlogician]

I heard/read somewhere that it might be possible for James Webb to gather limited data about exoplanet atmospheres. Maybe I misunderstood. Perhaps it was posed as a remote possibility or something.

[HappySkeptic]

I'm most interested in observations of extra-solar planets.  However, even Webb isn't going to be able to see earth-like planets or measure their atmosphere.  That will likely require LUVOIR or a set of space-based telescopes doing interferometry.

depends on what you mean by “see”.   dozens of exoplanets have already been directly imaged from the ground.

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There are also several additional Hubble scale optical snd near optical space telescopes in the works, scheduled to be launched in the next 5 years.   They either cover different wave length from hubble, or capable of scanning the sky much more quickly than hubble so as to be able to provide full coverage of the sky at bear hubble resolutions.    These are Less flashy than JWST, but perhaps promise work of comparable importance.

habitable exoplanets can only be "seen" through occultation of their star.  This drastically limits the number we will find, and the signal is nowhere nearly large enough for us to measure atmospheres.

Sure, we can directly see some gas giants, especially when around dim stars, but they aren't habitable.  We are able to measure some large-planet atmospheres as well. Perhaps Webb will be able to measure some Titan-like atmospheres, because it is so thick.

To really get to see habitable planets directly, and do atmospheric measurements, we would need something more than what has been proposed.  I saw an idea for an occulting disk, thousands of kilometers from a hubble-size telescope.  That should provide the ability to cut out the starlight and see and measure planets.  I've also seen ideas for multi-telescope interferometry - though I'm not sure those will get the signal-to-noise with only internal star occultation.

[Anomalocaris]

An occulting habitable planet might reveal the content of its atmosphere by absorption of star light refracted though its atmosphere during the occultation.   Admittedly the signal would be extremely weak.   But given that 30 years ago we were confidently predicting stellar occultation by habitable planet would itself be too weak a phenomenon to ever be useful, I suspect absorption by atmosphere during occultation would also be teased out of the data within a decade or two.


Here is an animation of the deployment of the perspective occulting disk for a space telescope https://exoplanets.nasa.gov/resources/21...animation/

[BrianSoddingBoru4]

There is a campaign to get the telescope renamed.

https://www.nature.com/articles/d41586-021-02010-x

Basically, Webb was a politican during the "lavender scare", and at least one gay scientist was fired from NASA while Webb was administrator, for being gay.

I don't think this effort should succeed, unless it is shown that Webb was an anti-gay instigator.  No-one living before 2000 is going to be "pure enough" for culture activists.  Perhaps we can never name anything after former politicians?

That said, a "Carl Sagan Telescope" has a nice ring to it, and pro-marijuana activists will be onboard.

Given what Webb is accused of, it would be appropriate to re-name the telescope ‘Butch’.

Boru

[Fake Messiah]

Or maybe they could re-name the telescope into "Bill Nye the Science Guy".

Anyway, the telescope is set to launch on Dec. 18, 2021. And it will take six months for it to unravel, cool down, and be fully operational.