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As a layman I get the feeling that JWST is showing us more detailed things we'd already seen than brand new ones. I remember being moved by the Hubble deep fiel

As a layman I get the feeling that JWST is showing us more detailed things we'd already seen than brand new ones. I remember being moved by the Hubble deep field, where a long exposure revealed that what looked like an empty patch of the sky was anything but. Are we reaching the point of diminishing returns of what a reasonably sized (for our current rockets) space telescope can see?

soulofmischief 3y ago
JWST is an infrared scope of a magnitude never before employed. Astronomy is more about collecting data than anything else, pretty images are a welcome side-effect. JWST will be extremely beneficial for deep-space exploration. It's worth reading about!
digging 3y ago
> Are we reaching the point of diminishing returns of what a reasonably sized (for our current rockets) space telescope can see? No, not as far as I know (also a layperson). It's just that we've already seen the incredible leap of "there's nothing here" -> "there's things here". The JWST is still a massive leap in capabilities, but you aren't going to be as impressed at seeing intricate structures inside a galaxy that once appeared smooth. The JWST is truly a new era of exploring the early universe, but it might not have the same "wow" factor.
potamic 3y ago
They did discover several galaxies beyond redshift 11 that Hubble cannot see. I'm not in the field, but venturing a guess here that they might want to prioritise getting images of known objects first, because there must be so much active research that can immediately benefit from the new detail. Over time I hope they will dedicate time for some wild hunches like Hubble did and open up something yet unknown.
hn8305823 3y ago
The Hubble deep fields take many days/weeks/months of exposure time. The deep fields released from JWST so far have been just hours long... There are a lot of different proposals being rapidly shot in these early year(s) of the telescope. Later on there will certainly be longer exposures.
- tambourine_man 3y ago
  I'm eager to see what JWST can do with more than 48h of exposure. It should be amazing. I'm wondering why they're choosing to shot other stuff before.
  - adgjlsfhk1 3y ago
    Because telescope time is expensive. If you do a 1 week deepfield, you can't use the telescope for anything else for 1 week. You get more discoveries earlier by doing all of your hour long shots first.
nologic01 3y ago
Discovering brand new things at a constant rate is probably not a realistic expectation. The 20th century has been an extraordinary journey for astronomy that cannot possibly continue indefinitely (same with other parts of fundamental science). We went from barely a sense what our galaxy is about, to discovering an extraordinary number of exotic astronomical objects by progressively expanding the window into radio, x-ray, gamma rays, gr waves etc. But I don't think its true that future astronomers / space telescopes are condemned to boring hires pictures of known stuff. The excitement is not in the visual impression but in what it might tell us about the universe. In the end what matters is whether we understand what is happening (e.g., in this instance how planetary systems like our very own are forming). So while the visual impression might not alter much, the quantitative detail may be fixing the physics or even prompting completely new theories. Remember sometimes even the stuff you don't see can bring about a revolution (dark matter, dark energy).
retrac 3y ago
> Are we reaching the point of diminishing returns of what a reasonably sized (for our current rockets) space telescope can see? In terms of sensitivity, yes. Collecting more light needs more light-collecting material, which ultimately means more mirror, or detector, surface area. Little more gain to be had there. We're not going to see much more that's really, really faint. But we're just getting started with resolution. Apertures can be synthesized in software. Theoretically, a handful of space telescopes, orbiting the Sun, linked together, could have an angular resolution equivalent to that of a physical telescope with a mirror the same diameter of the orbit. Not the light sensitivity (since the "mirror" is mostly empty space), but it would have the ability to distinguish between two points like such a giant telescope would. This has been done with radio astronomy already; things have just recently gotten fast enough for aperture synthesis at infrared wavelengths; optical is probably not too far behind.
- adgjlsfhk1 3y ago
  I think optical is pretty far behind. EHT was already dealing with 100s of TB of data per telescope. Going to visual turns that into ~10s of PB. I think the more likely advance is some way of doing space based radio wave interferometry.
BurningFrog 3y ago
JWT doesn't have much more detail than Hubble, but it observes infrared frequencies, which is a whole new view of the universe.

soulofmischief 3y ago

JWST is an infrared scope of a magnitude never before employed. Astronomy is more about collecting data than anything else, pretty images are a welcome side-effect. JWST will be extremely beneficial for deep-space exploration. It's worth reading about!

digging 3y ago

> Are we reaching the point of diminishing returns of what a reasonably sized (for our current rockets) space telescope can see? No, not as far as I know (also a layperson). It's just that we've already seen the incredible leap of "there's nothing here" -> "there's things here". The JWST is still a massive leap in capabilities, but you aren't going to be as impressed at seeing intricate structures inside a galaxy that once appeared smooth. The JWST is truly a new era of exploring the early universe, but it might not have the same "wow" factor.

potamic 3y ago

They did discover several galaxies beyond redshift 11 that Hubble cannot see. I'm not in the field, but venturing a guess here that they might want to prioritise getting images of known objects first, because there must be so much active research that can immediately benefit from the new detail. Over time I hope they will dedicate time for some wild hunches like Hubble did and open up something yet unknown.

hn8305823 3y ago

The Hubble deep fields take many days/weeks/months of exposure time. The deep fields released from JWST so far have been just hours long... There are a lot of different proposals being rapidly shot in these early year(s) of the telescope. Later on there will certainly be longer exposures.

tambourine_man 3y ago
I'm eager to see what JWST can do with more than 48h of exposure. It should be amazing. I'm wondering why they're choosing to shot other stuff before.
- adgjlsfhk1 3y ago
  Because telescope time is expensive. If you do a 1 week deepfield, you can't use the telescope for anything else for 1 week. You get more discoveries earlier by doing all of your hour long shots first.

nologic01 3y ago

Discovering brand new things at a constant rate is probably not a realistic expectation. The 20th century has been an extraordinary journey for astronomy that cannot possibly continue indefinitely (same with other parts of fundamental science). We went from barely a sense what our galaxy is about, to discovering an extraordinary number of exotic astronomical objects by progressively expanding the window into radio, x-ray, gamma rays, gr waves etc. But I don't think its true that future astronomers / space telescopes are condemned to boring hires pictures of known stuff. The excitement is not in the visual impression but in what it might tell us about the universe. In the end what matters is whether we understand what is happening (e.g., in this instance how planetary systems like our very own are forming). So while the visual impression might not alter much, the quantitative detail may be fixing the physics or even prompting completely new theories. Remember sometimes even the stuff you don't see can bring about a revolution (dark matter, dark energy).

retrac 3y ago

> Are we reaching the point of diminishing returns of what a reasonably sized (for our current rockets) space telescope can see? In terms of sensitivity, yes. Collecting more light needs more light-collecting material, which ultimately means more mirror, or detector, surface area. Little more gain to be had there. We're not going to see much more that's really, really faint. But we're just getting started with resolution. Apertures can be synthesized in software. Theoretically, a handful of space telescopes, orbiting the Sun, linked together, could have an angular resolution equivalent to that of a physical telescope with a mirror the same diameter of the orbit. Not the light sensitivity (since the "mirror" is mostly empty space), but it would have the ability to distinguish between two points like such a giant telescope would. This has been done with radio astronomy already; things have just recently gotten fast enough for aperture synthesis at infrared wavelengths; optical is probably not too far behind.

adgjlsfhk1 3y ago
I think optical is pretty far behind. EHT was already dealing with 100s of TB of data per telescope. Going to visual turns that into ~10s of PB. I think the more likely advance is some way of doing space based radio wave interferometry.

BurningFrog 3y ago

JWT doesn't have much more detail than Hubble, but it observes infrared frequencies, which is a whole new view of the universe.