Page 22 of 29 FirstFirst ...
12
20
21
22
23
24
... LastLast
  1. #421
    Banned Lilithvia's Avatar
    Join Date
    Sep 2017
    Location
    No matter the topic, someone will find a way to redirect it to complain about their current aggro.
    Posts
    4,104
    I like the guy talking to the host of this broadcast. He reminds me of Sigma from OW if Sigma was sane and not being manipulated by a terrorist organization

    OT: The currently released picture from JWST is absolutely mindblowing

  2. #422

  3. #423
    ^ Absolutely stunning.

    This visual (originally made for Hubble) should provide some context for the size of the area of space photographed for the Webb Deep Field:


  4. #424
    The Unstoppable Force PC2's Avatar
    Join Date
    Feb 2015
    Location
    California
    Posts
    21,520
    Quote Originally Posted by DarkAmbient View Post
    ^ Absolutely stunning.

    This visual (originally made for Hubble) should provide some context for the size of the area of space photographed for the Webb Deep Field:

    [IMG]https://i.imgur.com/Ym0Dke5.gif[IMG]
    Yeah and also nobody should be surprised when the next big telescope after the James Webb Telescope provides another similar improvement in resolution and scale. In every square meter of space there is a near infinite amount of information that could be understood with a more advanced measurement and data processing scheme.

    The reason I bring this up is because scientists and engineers have a long record of thinking that the technology in the current era is close to hitting the ultimate limits imposed by physics, which is a misunderstanding in most cases.
    Last edited by PC2; 2022-07-12 at 08:48 PM.

  5. #425
    Herald of the Titans Tuor's Avatar
    Join Date
    Sep 2010
    Location
    Valinor
    Posts
    2,659
    Quote Originally Posted by PC2 View Post
    Yeah and also nobody should be surprised when the next big telescope after the James Webb Telescope provides another similar improvement in resolution and scale. In every square meter of space there is a near infinite amount of information that could be understood with a more advanced measurement and data processing scheme.

    The reason I bring this up is because scientists and engineers have a long record of thinking that the technology in the current era is close to hitting the ultimate limits imposed by physics, which is a misunderstanding in most cases.
    The next telescope will be Nancy Roman telescope to be launched in 2027. It has the same size of the mirror has the hubble, but with better capabilities, so hardly to happen.

  6. #426
    The Unstoppable Force PC2's Avatar
    Join Date
    Feb 2015
    Location
    California
    Posts
    21,520
    Quote Originally Posted by Tuor View Post
    The next telescope will be Nancy Roman telescope to be launched in 2027. It has the same size of the mirror has the hubble, but with better capabilities, so hardly to happen.
    It could easily happen as long as nothing catastrophic happens to civilization and as long as you make a proper comparison. My Google results are saying that the James Webb Telescope is only 100x more powerful than the Hubble Telescope which was launched in 1990. 32 years ago. So if the scientists and engineers working on the Nancy Roman telescope can't get another 100x improvement by 2027 I won't hold it against them because of the time frame.
    Last edited by PC2; 2022-07-13 at 12:57 AM.

  7. #427
    Quote Originally Posted by PC2 View Post
    It could easily happen as long as nothing catastrophic happens to civilization and as long as you make a proper comparison. My Google results are saying that the James Webb Telescope is only 100x more powerful than the Hubble Telescope which was launched in 1990. 32 years ago. So if the scientists and engineers working on the Nancy Roman telescope can't get another 100x improvement by 2027 I won't hold it against them because of the time frame.
    Saying that JWST is 100x more powerful than HST is both an exaggeration and a misunderstanding of how astronomy actually works.

    There are many parameters when comparing telescopes but some are what they observe, how quickly, and how accurately. HST was primarily for visible light - whereas JWST is for infrared so they are more complementary than one being superior to the other.

    How quickly depends on the area of the telescope and JWST is about 6 times larger, how accurately in terms of resolution is limited on the diameter divided by the wave-length and even if JWST has a diameter that is almost 3 times larger its observing longer wave-lengths so it sort of evens out. The latter also explains why within JWST the NIR-camera is split into long and short infrared (and duplicated as well) and the short infrared detectors has a lot more camera sensors - because it can use the higher resolution.

    The more direct competitor with JWST were the Herschel Space Observatory, which in size is between HST and JWST - but possibly JWST has 100x the PR (NASA really beats ESA on that part).
    Last edited by Forogil; 2022-07-13 at 05:01 PM.

  8. #428
    The Unstoppable Force PACOX's Avatar
    Join Date
    Jul 2010
    Location
    ██████
    Posts
    24,685
    I'm not even sure if there's a definite replacement for the Hubble

    Resident Cosplay Progressive

  9. #429
    Banned Lilithvia's Avatar
    Join Date
    Sep 2017
    Location
    No matter the topic, someone will find a way to redirect it to complain about their current aggro.
    Posts
    4,104
    Quote Originally Posted by PACOX View Post
    I'm not even sure if there's a definite replacement for the Hubble
    it's called sending a mission to Hubble to upgrade it

  10. #430
    Herald of the Titans Tuor's Avatar
    Join Date
    Sep 2010
    Location
    Valinor
    Posts
    2,659
    JWST odissey continues. It might have already had discovered the most distant galaxy known.


    And this is just the begining .

  11. #431
    Quote Originally Posted by Forogil View Post
    Saying that JWST is 100x more powerful than HST is both an exaggeration and a misunderstanding of how astronomy actually works.

    There are many parameters when comparing telescopes but some are what they observe, how quickly, and how accurately. HST was primarily for visible light - whereas JWST is for infrared so they are more complementary than one being superior to the other.

    How quickly depends on the area of the telescope and JWST is about 6 times larger, how accurately in terms of resolution is limited on the diameter divided by the wave-length and even if JWST has a diameter that is almost 3 times larger its observing longer wave-lengths so it sort of evens out. The latter also explains why within JWST the NIR-camera is split into long and short infrared (and duplicated as well) and the short infrared detectors has a lot more camera sensors - because it can use the higher resolution.

    The more direct competitor with JWST were the Herschel Space Observatory, which in size is between HST and JWST - but possibly JWST has 100x the PR (NASA really beats ESA on that part).
    James Webb takes visible light images as well. It’s the successor and upgrade of Hubble.

  12. #432
    Quote Originally Posted by Snuke View Post
    James Webb takes visible light images as well. It’s the successor and upgrade of Hubble.
    Nope(*) and nope.

    JWST is a step forward, but can we stop with the fan-boy exaggerations?

    The reason is that we want to continue to maintain Hubble (and successors) while JWST is running, since they complement each other.
    Additionally we also need other parts of the light spectrum (radio(-interferometry) on earth, X-ray satellites and more) and non-light astronomy (gravitational and neutrinos etc).

    *: Technically JWST can capture some visible light, but only red and not the entire visible spectrum (380 to 750 nm).

    Specifically:
    https://jwst.nasa.gov/content/observ...ts/nircam.html has a range of 600 to 5,000 nm (same for the spectrograph).
    https://jwst.nasa.gov/content/observ...ents/miri.html has a range of 5,000 to 28,000 nm.

    Hubble's WFC3 can capture all of visible light and some: one detector for 200 to 1,000 nm (so even some UV), and one for NIR: 850 to 1,700 nm; https://wfc3.gsfc.nasa.gov/overview/
    (As for why the instruments are split and why they have different number of CCD cells, please see my previous post.)

    Note that many astronomical images have "fake colors", don't let that fool you.

  13. #433
    Quote Originally Posted by Forogil View Post
    Nope(*) and nope.

    JWST is a step forward, but can we stop with the fan-boy exaggerations?

    The reason is that we want to continue to maintain Hubble (and successors) while JWST is running, since they complement each other.
    Additionally we also need other parts of the light spectrum (radio(-interferometry) on earth, X-ray satellites and more) and non-light astronomy (gravitational and neutrinos etc).

    *: Technically JWST can capture some visible light, but only red and not the entire visible spectrum (380 to 750 nm).

    Specifically:
    https://jwst.nasa.gov/content/observ...ts/nircam.html has a range of 600 to 5,000 nm (same for the spectrograph).
    https://jwst.nasa.gov/content/observ...ents/miri.html has a range of 5,000 to 28,000 nm.

    Hubble's WFC3 can capture all of visible light and some: one detector for 200 to 1,000 nm (so even some UV), and one for NIR: 850 to 1,700 nm; https://wfc3.gsfc.nasa.gov/overview/
    (As for why the instruments are split and why they have different number of CCD cells, please see my previous post.)

    Note that many astronomical images have "fake colors", don't let that fool you.
    Red and yellow. And, as per NASA,

    Webb often gets called the replacement for Hubble, but we prefer to call it a successor.
    Nothing I said was incorrect.

  14. #434
    Quote Originally Posted by Snuke View Post
    Red and yellow. And, as per NASA,
    Not really. NASA writes red and orange, and even that is a bit inaccurate and orange light is to a large degree outside the range. Sometimes they use "gold-color", I don't know how they got that name - gold has a spectral line exactly at 600 nm (which is the limit), but looks yellow and most people don't have pure gold to look at.

    https://asd.gsfc.nasa.gov/blueshift/...e-false-color/

    Quote Originally Posted by Snuke View Post
    Nothing I said was incorrect.
    Claiming that it can take visible light images while unable to see most of the visible spectrum isn't really correct.

    People promoting JWST at NASA have called it successor to Hubble to sell it, and as stated above it isn't really true in terms of observations.

    It is true that it is the flagship successor - as being the costliest mission in that division. It's somewhat true in the technological sense as it was designed later and had more advanced sensors - but still aiming to observe different things.
    Scientifically it depends on what you are aiming for - for some scientific goals JWST will go further than HST (distant galaxies, looking inside dust clouds) - for others HST (like Mrk 1337) offers unique insights.

  15. #435
    Herald of the Titans Tuor's Avatar
    Join Date
    Sep 2010
    Location
    Valinor
    Posts
    2,659
    Quote Originally Posted by Snuke View Post
    James Webb takes visible light images as well. It’s the successor and upgrade of Hubble.
    JWST only sees infrared, i posted another video where is explained that the mirror is not designed to reflect visible light, you can try at home, take a piece of gold and look how bad the reflection of gold is for visible light. Anyway all intruments are infrared. Also don't presume the JWST can see all the infrared spectrum because he can't, JWST is not sensible to the infrared frequenciencies closer to radio.

  16. #436
    Quote Originally Posted by Tuor View Post
    JWST only sees infrared, i posted another video where is explained that the mirror is not designed to reflect visible light, you can try at home, take a piece of gold and look how bad the reflection of gold is for visible light. Anyway all intruments are infrared. Also don't presume the JWST can see all the infrared spectrum because he can't, JWST is not sensible to the infrared frequenciencies closer to radio.

    Again, no, it doesn’t. It sees all the way into the yellow spectrum of visible light.

  17. #437
    Quote Originally Posted by Tuor View Post
    JWST only sees infrared, i posted another video where is explained that the mirror is not designed to reflect visible light, you can try at home, take a piece of gold and look how bad the reflection of gold is for visible light. Anyway all intruments are infrared. Also don't presume the JWST can see all the infrared spectrum because he can't, JWST is not sensible to the infrared frequenciencies closer to radio.
    Yes, but looking more I realized that there's another reason JWST cannot go below 600 nm in a meaningful way.

    To get color images for near-infrared they use filters that only pass a "wide" range of wavelengths - and the lowest one, F070W, blocks light below 600 nm (and above 780 nm or so - but there's another filter for that etc). Obviously that limit was selected together with the rest of it.

    Or in other words JWST is deliberately designed to not see below 600 nm.

  18. #438
    The Unstoppable Force PACOX's Avatar
    Join Date
    Jul 2010
    Location
    ██████
    Posts
    24,685
    Definitely forgot to post this with all the JWST stuff.

    SLS is expected to make its maidan launch Aug 29th. Realistically probably a day or two later but we have a date set thats not months away.

    Resident Cosplay Progressive

  19. #439
    The Undying cubby's Avatar
    Join Date
    Aug 2007
    Location
    the Quiet Room
    Posts
    33,624
    Quote Originally Posted by PACOX View Post
    Definitely forgot to post this with all the JWST stuff.

    SLS is expected to make its maidan launch Aug 29th. Realistically probably a day or two later but we have a date set thats not months away.
    That is great news. Looking forward to seeing that monster go up.

  20. #440
    The Undying cubby's Avatar
    Join Date
    Aug 2007
    Location
    the Quiet Room
    Posts
    33,624
    What's the over/under on it actually launching in the month of August?

    I sincerely hope it goes off without a hitch on the 29, it will be amazing to get a rocket around the moon and back.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •