New Webb image captures clearest view of Neptune’s rings in decades(nasa.gov)
nasa.gov
New Webb image captures clearest view of Neptune’s rings in decades
https://www.nasa.gov/feature/goddard/2022/new-webb-image-captures-clearest-view-of-neptune-s-rings-in-decades/
132 comments
God what an incredible story, I love hearing it every time. The prediction of a planet using science and maths.
The follow up (correct me on the details here) is that they later measured Mercury’s orbit to a high precision, estimated that some body was disturbing Mercury’s orbit, and went looking again to repeat Sir Isaac’s miraculous math. But… nothing was there. It turned out Mercury orbits at relativistic speeds and Newton’s model wasn’t taking that into account.
Vaguely remember this from Kuhn’s Structure of Scientific Revolutions
The follow up (correct me on the details here) is that they later measured Mercury’s orbit to a high precision, estimated that some body was disturbing Mercury’s orbit, and went looking again to repeat Sir Isaac’s miraculous math. But… nothing was there. It turned out Mercury orbits at relativistic speeds and Newton’s model wasn’t taking that into account.
Vaguely remember this from Kuhn’s Structure of Scientific Revolutions
It isn't from Mercury's speed (Special relativity) it's from proximity to the Sun (General Relativity).
Indeed! It is a quite telling story about the messy inner workings of scientific discoveries.
In the case of Neptune, Le Verrier hit the nail right on its head (where others suggested a limit to Newton's theory of gravity). This tremendous feat gave him all the reason to search for other perturbations around the sky to find unknown objects.
So, by 1859 he was the first to find Mercury not completely adhering to Newtonian mechanics (anomalous rate of precession of the perihelion[0]), therefore he postulated smaller unseen objects in its vicinity, even naming a possible planet Vulcan.
But there, he was wrong and Newton's law really hit a limit here at such proximity to the sun.
Ironically not at "long distances" as suggested in the anomaly of Uranus' orbit. Also, Einstein within his GR framework correctly predicted the value of deflection of "starlight passing very close to the sun" in 1915 which was validated by the measurements of Eddington taking advantage of a total eclipse in 1919 --- a natural occurring coronagraph (a big moon) of the Sun from Earth's view ;)
P.S.: I forgot to mention D'Arrest[1] role in finding Neptune in the sky:
> While still a student at the University of Berlin, d'Arrest was party to Johann Gottfried Galle's search for Neptune. On 23 September 1846, he suggested that a recently drawn chart of the sky, in the region of Urbain Le Verrier's predicted location, could be compared with the current sky to seek the displacement characteristic of a planet, as opposed to a stationary star.
[0]https://en.m.wikipedia.org/wiki/Tests_of_general_relativity#...
[1]https://en.m.wikipedia.org/wiki/Heinrich_Louis_d%27Arrest#Bi...
In the case of Neptune, Le Verrier hit the nail right on its head (where others suggested a limit to Newton's theory of gravity). This tremendous feat gave him all the reason to search for other perturbations around the sky to find unknown objects.
So, by 1859 he was the first to find Mercury not completely adhering to Newtonian mechanics (anomalous rate of precession of the perihelion[0]), therefore he postulated smaller unseen objects in its vicinity, even naming a possible planet Vulcan.
But there, he was wrong and Newton's law really hit a limit here at such proximity to the sun.
Ironically not at "long distances" as suggested in the anomaly of Uranus' orbit. Also, Einstein within his GR framework correctly predicted the value of deflection of "starlight passing very close to the sun" in 1915 which was validated by the measurements of Eddington taking advantage of a total eclipse in 1919 --- a natural occurring coronagraph (a big moon) of the Sun from Earth's view ;)
P.S.: I forgot to mention D'Arrest[1] role in finding Neptune in the sky:
> While still a student at the University of Berlin, d'Arrest was party to Johann Gottfried Galle's search for Neptune. On 23 September 1846, he suggested that a recently drawn chart of the sky, in the region of Urbain Le Verrier's predicted location, could be compared with the current sky to seek the displacement characteristic of a planet, as opposed to a stationary star.
[0]https://en.m.wikipedia.org/wiki/Tests_of_general_relativity#...
[1]https://en.m.wikipedia.org/wiki/Heinrich_Louis_d%27Arrest#Bi...
Wow, that's cool https://en.wikipedia.org/wiki/Vulcan_(hypothetical_planet)
I read this book which was a great read https://www.amazon.co.uk/Hunt-Vulcan-Discovered-Relativity-D...
Known for: Not discovering Neptune
https://en.wikipedia.org/wiki/James_Challis
You mean perhaps 1.5^2?
Yeah, ~ 1.5x in relation to their respective aphelions (farthest orbital distance to the Sun)
But, yes - if you will - the area of the solar system consequently has more than doubled; which has nicer ring to it :)
To be exact if my numbers are correct:
πab = πa² √(1-e²)
Uranus (a = 19.19126 AU; e = 0.04717)
⇒ ~ 1155.755 AU²
Neptune (a = 30.07 AU; e = 0.008678 (what a neat circle!))
⇒ ~ 2840.54 AU²
i.e. approx. 2.46x the former area
But, yes - if you will - the area of the solar system consequently has more than doubled; which has nicer ring to it :)
To be exact if my numbers are correct:
πab = πa² √(1-e²)
Uranus (a = 19.19126 AU; e = 0.04717)
⇒ ~ 1155.755 AU²
Neptune (a = 30.07 AU; e = 0.008678 (what a neat circle!))
⇒ ~ 2840.54 AU²
i.e. approx. 2.46x the former area
This is certainly impressive, thanks!
Wow! If anyone is curious as to why Triton is so bright...
> Covered in a frozen sheen of condensed nitrogen, Triton reflects an average of 70 percent of the sunlight that hits it. It far outshines Neptune in this image because the planet’s atmosphere is darkened by methane absorption at these near-infrared wavelengths.
That's pretty neat!
> Covered in a frozen sheen of condensed nitrogen, Triton reflects an average of 70 percent of the sunlight that hits it. It far outshines Neptune in this image because the planet’s atmosphere is darkened by methane absorption at these near-infrared wavelengths.
That's pretty neat!
The fact that methane absorbs infrared/near-infrared frequencies is also the mechanism that causes it to be a greenhouse gas.
https://en.wikipedia.org/wiki/Neptune#Internal_structure
> "At a depth of 7,000 km, the conditions may be such that methane decomposes into diamond crystals that rain downwards like hailstones.... the top of the mantle may be an ocean of liquid carbon with floating solid 'diamonds'."
> "At a depth of 7,000 km, the conditions may be such that methane decomposes into diamond crystals that rain downwards like hailstones.... the top of the mantle may be an ocean of liquid carbon with floating solid 'diamonds'."
Thanks for pointing this out, that is truly fascinating to imagine. I'm now short on sleep due to the wikipedia rabbit hole :)
Also explains why the rings are brighter than the planet here, when they were all but invisible to Voyager 2.
> 70 percent of the sunlight that hits it
It looks like that's comparable to fresh snow or a glacier?
It looks like that's comparable to fresh snow or a glacier?
Better than a glacier but worse than fresh snow. "More than 80 to 90 percent of the sunlight falling on fresh snow is reflected back into space, compared to 15 to 35 percent of the sunlight reflected by most ice."[1].
[1]https://earthobservatory.nasa.gov/features/DirtySnow/page2.p...
[1]https://earthobservatory.nasa.gov/features/DirtySnow/page2.p...
Is there a good chemical / spatial argument for why this is so?
I think it is because a flat surface gets one chance to reflect by refraction and predominantly only at a shallow angles. A bunch of micro surfaces in an aggregate formation mean it could bounce around multiple times and then head out, or pass through the ice medium and then bounce back out when it exits and reflects off more. Absorption wise a greater ratio of air to ice means it will absorb less often too over the same distance through snow.
This is correct, it's why things like solar panels have a surprisingly low albedo despite being mostly black, they are completely flat.
woah
I originally thought it was a star
I originally thought it was a star
For a second I thought this was Saturn and said “don’t we have better images of this?” Then I actually read it’s Neptune and realized all our good images of it come from probes. It’s crazy JWST can just see the rings and the moons, incredible observatory.
My understanding is that this isn't even the 'good' camera, just the comparatively low-resolution infrared one.
Webb has two main cameras, NIRCAM for near-infrared, MIRI for mid-infrared. MIRI is lower resolution because it's looking at longer wavelengths.
This image is from NIRCAM, so it's the highest res Webb can do. Neptune is small in the image because it's very far away. The images you see of detailed nebulae are so high res because, even though they're further away, those nebulae are enormous.
This image is from NIRCAM, so it's the highest res Webb can do. Neptune is small in the image because it's very far away. The images you see of detailed nebulae are so high res because, even though they're further away, those nebulae are enormous.
I really hope to see a Cassini or Juno like probe to visit Neptune and Uranus in my lifetime.
As good as JWST is and these images are, these objects are so distant the only high-res imagery you can get is by visiting them. Prior to New Horizons, our best image of Pluto, for example, was a few blurry pixels and that remained the case even until New Horizons was 99% of the way there.
As good as JWST is and these images are, these objects are so distant the only high-res imagery you can get is by visiting them. Prior to New Horizons, our best image of Pluto, for example, was a few blurry pixels and that remained the case even until New Horizons was 99% of the way there.
I would say I'd like this for all the planets. What Cassini and Juno brought us is simply stunning. Some of the details visible in Jupiter's clouds or Saturn's rings have just been amazing.
The images Voyagers and New Horizons brought are nice and not to be discounted, but fly-bys vs orbit insertion missions just not the same. We should have oribters parked around each of our local major bodies. We should then have rovers on all of the solid bodies (that won't melt the thing in mere hours) after that. The MRO is such a great example.
The images Voyagers and New Horizons brought are nice and not to be discounted, but fly-bys vs orbit insertion missions just not the same. We should have oribters parked around each of our local major bodies. We should then have rovers on all of the solid bodies (that won't melt the thing in mere hours) after that. The MRO is such a great example.
Even the Rosetta/Philae images of the comet 67P/Churyumov–Gerasimenko are out of this world!
https://www.esa.int/Science_Exploration/Space_Science/Rosett...
https://www.esa.int/Science_Exploration/Space_Science/Rosett...
From that link:
Launch: 2 March 2004
Mission end: 30 September 2016
Then, a bit lower on the page: 786 days in space
Huh? Anyone got insights on what type of math was used here? Is there mm/inch type conversion problem? Am I just dumb? 12 years * 365 > 786.
Launch: 2 March 2004
Mission end: 30 September 2016
Then, a bit lower on the page: 786 days in space
Huh? Anyone got insights on what type of math was used here? Is there mm/inch type conversion problem? Am I just dumb? 12 years * 365 > 786.
If I had Bill Gates' money, I'd be funding that.
Elon is fixing the launch cost side of it.
If you have a probe design process that doesn't go through the US congress, it should be substantially faster and cheaper.
If you have a probe design process that doesn't go through the US congress, it should be substantially faster and cheaper.
I often ponder if there is some sort of heuristic law that determines the level of bureaucracy based on an organization's structure.
In the case of the Congress, the problem is not bureaucratic slowness but the desire that as many companies from every state as possible took part in the project. Every congressperson wants to bring some business to their constituencies; what this business ultimately achieves may be of secondary importance.
I think all organizations drift toward dysfunction over time.
Those that have no competition inevitably end up there.
Those that have no competition inevitably end up there.
I think there's an inverse square rule relating the size (number of employees/managment) to the dysfunction
The amount of time it takes a group of people who decided to go somewhere to actually get in their cars and get moving goes up as the square of the number of people.
In that scenario, there's an inverse square law of how much cannabis was consumed between that group of people just to come to a consensus of where to go to get food that everyone has already agreed to being hungry an hour ago.
You may be in luck with Uranus: https://en.m.wikipedia.org/wiki/Uranus_Orbiter_and_Probe
As I get older, that's always good to hear, doc.
Not only is this childish but the Gods name isn’t pronounced like that
Hey, I know! Those kinds of jokes are never funny. https://m.youtube.com/watch?v=x5lWowU52t8
I’m wonder if they can miniaturize a camera and propulsion system enough that can travel fast enough to just take pics and bring them back instead of needing large antennas/power modules to transmit back in say a year or so?
You don't need a very high-powered radio if a) you have plenty of time to transmit the data back and b) you can afford to build large receiving telescopes back on Earth. The latter we already do have, although bigger the better, and the former is just a case of patience. Galileo, famously, was unable to fully unfold its high-gain antenna and had to transmit everything via the much lower-bandwidth low-gain antenna. The ability to batch the probe software to use higher-efficiency data encoding and modulation meant this was not as disastrous as it could have been. This failure mode was also likely the reason that both Cassini and New Horizons opted for a more traditional rigid dish antenna.
No. It's very hard to go fast, and to get to Neptune, you need to burn a lot of fuel to get there. Getting home needs a whole lot more fuel too. Space travel is hard. You can go with lower energy transfer orbits, and wait forever to get there, or you can go high-speed and carry a ton of fuel with you.
Getting home requires no additional fuel if using a free-return trajectory and you don't want to be there for long.
Jones, Drew Ryan, 2016, "Trajectories for flyby sample return at Saturn's moons", https://hdl.handle.net/2014/46163, Root, V1 at https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&versi...
> Here an alternative and novel mission concept is analyzed to return a sample from either Titan or Enceladus, without capturing at Saturn. Instead, ballistic free return trajectories are sought which also incur a close encounter of the icy moon. The spacecraft could sample a plume (or upper atmosphere) during the hyperbolic flyby.
The time frames are on the order of 20 years.
OTOH, you would only have a few dozen hours near the planet. ("This 16 year mission, has the Titan flyby occurring about 10 hours prior to Saturn closest approach").
Jones, Drew Ryan, 2016, "Trajectories for flyby sample return at Saturn's moons", https://hdl.handle.net/2014/46163, Root, V1 at https://dataverse.jpl.nasa.gov/file.xhtml?fileId=53873&versi...
> Here an alternative and novel mission concept is analyzed to return a sample from either Titan or Enceladus, without capturing at Saturn. Instead, ballistic free return trajectories are sought which also incur a close encounter of the icy moon. The spacecraft could sample a plume (or upper atmosphere) during the hyperbolic flyby.
The time frames are on the order of 20 years.
OTOH, you would only have a few dozen hours near the planet. ("This 16 year mission, has the Titan flyby occurring about 10 hours prior to Saturn closest approach").
If you plot your trajectory so that you will just slightly in front of neptune, shouldn't you be able to use it's gravity to slingshot you back towards the inner solar system?
I'm skeptical that it's worth it... because higher powered radios just aren't that expensive, but it's not obviously (to me) impossible either.
Actually capturing your probe back in earth orbit... probably would be prohibitively expensive. But it seems like you could at least get it close by for a shorter communication distance.
I'm skeptical that it's worth it... because higher powered radios just aren't that expensive, but it's not obviously (to me) impossible either.
Actually capturing your probe back in earth orbit... probably would be prohibitively expensive. But it seems like you could at least get it close by for a shorter communication distance.
At the speeds needed to reach the outer Solar System in the first place, you would need to intersect the planet's surface (atmosphere, whatever) to get anywhere near the slingshot effect needed to throw you back to where you came from. Essentially it would only be possible with a black hole or another anomalously dense object.
It's like 12 years to get there and another 12 years to get back. Sending information back at the speed of light is preferable.
The mass to get the ship back and land safely is probably more than the antenna
Actually, Juno is very limited in it's capabilities when it comes to flagship missions like Cassini. Talking about Jupiter, Galileo was in the same capability range as the Cassini.
I think part of the problem with that is just how far away Neptune is.
Getting a probe like New Horizons to do a flyby requires a massive rocket. But to also have it be capable of slowing down to enter orbit and stick around means either it was moving slower on it's path to get there (so it takes a lot longer) or it has to carry a huge amount of fuel to burn to slow down (so it takes an even bigger rocket).
Neither option is great.
Getting a probe like New Horizons to do a flyby requires a massive rocket. But to also have it be capable of slowing down to enter orbit and stick around means either it was moving slower on it's path to get there (so it takes a lot longer) or it has to carry a huge amount of fuel to burn to slow down (so it takes an even bigger rocket).
Neither option is great.
So for any of these destinations there are really two options: fly-by or orbit insertion.
Pluto obviously was a fly-by. There were several reasons for this. Distance is a big one. Also, the more distant planets are the lower their orbital velocity. More distance = longer travel time. A higher velocity can reduce the travel time but you need to speed up at launch and slow down on arrival and that requires a higher delta-V budget. That requires extra mass of fuel, which becomes a vicious circle.
Pluto is tiny and far so a fly-by was really the only option. Even then it took 10 years to get there.
Neptune is more massive, closer and heavier. All of these help but if I'm reading [1] correctly, you'd still be realistically looking at a 30 year travel time for an insertion orbit. Having instruments hibernate for that long and work on the other end is really the biggest problem.
We're entering an era of super-heavy lifters. Maybe these will meaningfully increase the practical delta-V budgets.
Inserting a probe into orbit around Uranus (let alone Neptune) seems currently impractical just given how long it would take but that doesn't make me want it any less. Even a fly-by is better than nothing.
But the delta-V for Saturn, Uranus and Neptune are all roughly the same
[1]: https://en.wikipedia.org/wiki/Delta-v_budget
Pluto obviously was a fly-by. There were several reasons for this. Distance is a big one. Also, the more distant planets are the lower their orbital velocity. More distance = longer travel time. A higher velocity can reduce the travel time but you need to speed up at launch and slow down on arrival and that requires a higher delta-V budget. That requires extra mass of fuel, which becomes a vicious circle.
Pluto is tiny and far so a fly-by was really the only option. Even then it took 10 years to get there.
Neptune is more massive, closer and heavier. All of these help but if I'm reading [1] correctly, you'd still be realistically looking at a 30 year travel time for an insertion orbit. Having instruments hibernate for that long and work on the other end is really the biggest problem.
We're entering an era of super-heavy lifters. Maybe these will meaningfully increase the practical delta-V budgets.
Inserting a probe into orbit around Uranus (let alone Neptune) seems currently impractical just given how long it would take but that doesn't make me want it any less. Even a fly-by is better than nothing.
But the delta-V for Saturn, Uranus and Neptune are all roughly the same
[1]: https://en.wikipedia.org/wiki/Delta-v_budget
“Webb also captured seven of Neptune’s 14 known moons. Dominating this Webb portrait of Neptune is a very bright point of light sporting the signature diffraction spikes seen in many of Webb’s images, but this is not a star. Rather, this is Neptune’s large and unusual moon, Triton.
Covered in a frozen sheen of condensed nitrogen, Triton reflects an average of 70 percent of the sunlight that hits it. It far outshines Neptune in this image because the planet’s atmosphere is darkened by methane absorption at these near-infrared wavelengths. Triton orbits Neptune in an unusual backward (retrograde) orbit, leading astronomers to speculate that this moon was originally a Kuiper belt object that was gravitationally captured by Neptune. Additional Webb studies of both Triton and Neptune are planned in the coming year”
Covered in a frozen sheen of condensed nitrogen, Triton reflects an average of 70 percent of the sunlight that hits it. It far outshines Neptune in this image because the planet’s atmosphere is darkened by methane absorption at these near-infrared wavelengths. Triton orbits Neptune in an unusual backward (retrograde) orbit, leading astronomers to speculate that this moon was originally a Kuiper belt object that was gravitationally captured by Neptune. Additional Webb studies of both Triton and Neptune are planned in the coming year”
JWST's infrared capability is good at showing previously invisible details but I find it very odd its images keep looking like they're lower resolution and less detailed in the visual spectrum than Hubble images. I realize the observation times are shorter but jeez the JWST photo of Jupiter was garbage compared to a telescope that launched 32 years ago.
Roughly the angular reolution of a telescope is 1.22*wavelength/diameter. See https://en.wikipedia.org/wiki/Angular_resolution. Hubble uses visual light (0.5 um wavelength) while JWST uses IR (5 um wavelength) and beyond. So the wavelength for JWST is 10x larger than Hibble, but the diameter is only ~2.7X (Hubble 2.4m vs JWST 6.5m dia). So JWST resolution is 1.8x worse than Hubble.
That explains a lot, thank you.
This has been my general feeling, that the JWST photos are less visually interesting/detailed than even Hubble photos. I'm sure they have a ton of invisible data that scientists find invaluable, but they have thus far been largely visually unimpressive.
IMO, the JWST deep field is really impressive. There are something like 4x more galaxies in the background that just were invisible in Hubble due to redshift. JWST is heavily optimized for spectra, far away objects, and looking through gas clouds. For other stuff, you're probably better off using giant ground based telescopes.
The more spectacular Hubble photos are mosaics assembled from weeks or months of observation time. JWST is brand new and has been spending most of its time doing science observations rather than images for the press office. Give it a few years.
Sure, but you can't usefully observe Jupiter for that long, since it rotates.
You can stitch together images taken once per Jupiter day (although you'd lose fine details of weather patterns)
What photos are these? It has already produced images multiple times more detailed than their Hubble equivalents.
Here's a rando image of Neptune: https://hubblesite.org/contents/media/images/2020/59/4788-Im... I'm certain there are nicer ones. That site has most (all?) of Hubble's images available with keyword search. The reason the rings don't show up is the same reason that Neptune is its real color in the Hubble image. The Hubble image was taken in the visible spectrum, while JWST images are colorized infrared images.
It’s a near infrared telescope, on purpose. Not optimized for non-receding objects.
Its a pity we don't already have an orbiter around every planet!
Now that we have this wonderful tool, I really hope astronomers will dedicate 1 week of each year or one day of each month (depending on what orbits allow/make worthwhile) imaging bodies in our own solar system. I think it's a crime that this is the first new image of Neptune in 30 years.
Every advance in astronomical equipment or technique gives the lie to 'we already know about X, it's not that interesting' arguments. Longitudinal observation of our nearest neighbors are likely to significantly increase our knowledge, and these are the only bodies that are accessible to us barring some massive revolution in physics.
Every advance in astronomical equipment or technique gives the lie to 'we already know about X, it's not that interesting' arguments. Longitudinal observation of our nearest neighbors are likely to significantly increase our knowledge, and these are the only bodies that are accessible to us barring some massive revolution in physics.
Here are images of Neptune taken by Hubble last year:
https://esahubble.org/images/heic2113e/
from 2020:
https://www.nasa.gov/feature/goddard/2020/dark-storm-on-nept...
from 2018:
https://www.nasa.gov/feature/goddard/2019/hubble-reveals-dyn...
2016:
https://www.nasa.gov/image-feature/hubble-sees-new-dark-spot...
2013:
https://esahubble.org/images/opo1330c/
2011:
https://www.nasa.gov/mission_pages/hubble/multimedia/hubble-...
If you are more interested in images from ground based telescopes, here is Neptune from 2018 taken with the ESA Very Large Telescope:
https://solarsystem.nasa.gov/resources/936/neptune-from-the-...
https://esahubble.org/images/heic2113e/
from 2020:
https://www.nasa.gov/feature/goddard/2020/dark-storm-on-nept...
from 2018:
https://www.nasa.gov/feature/goddard/2019/hubble-reveals-dyn...
2016:
https://www.nasa.gov/image-feature/hubble-sees-new-dark-spot...
2013:
https://esahubble.org/images/opo1330c/
2011:
https://www.nasa.gov/mission_pages/hubble/multimedia/hubble-...
If you are more interested in images from ground based telescopes, here is Neptune from 2018 taken with the ESA Very Large Telescope:
https://solarsystem.nasa.gov/resources/936/neptune-from-the-...
those pictures suck though
The film Ad Astra may contain the most spectacular imagery of Neptune that is currently available. It’s done with reasonable verisimilitude (the planet, not what happened at the planet), based on what we know about it. Some liberties are taken with the thickness and relative velocity of the rings.
To an untrained eye, maybe.
There was a recent HN thread where I pontificated that a twin JW telescope could have been built and launched at 10% of the cost of #1. One of the (vehement) arguments against this was there weren't enough things to look at.
I just have to shake my head in amazement.
I just have to shake my head in amazement.
I wonder why you were downvoted. It's absolutely certain that all the big telescopes get way more proposals than there is available observation time. And not all the proposals that get rejected are of low quality.
Everywhere the JW scope points, even at areas thought to contain nothing, a lot is discovered. Given that it looks at the sky through a soda straw, there's no way that one machine could survey the universe. A fleet of them would be needed.
This isn't the first new image of Neptune in the last 30 years. Astronomers have imaged Neptune since Voyager, and the Hubble Space Telescope was used for this as well. See here: https://hubblesite.org/contents/media/images/2021/047/01FM0Q...
Thanks, I misread something on the NASA page. But still, I'd like more emphasis on studying reachable heavenly bodies even if it slightly delays our speculation into more distant ones.
It's the first image of Neptune's rings since Voyager 2, I've seen this mistake made a few times now
> the first new image of Neptune in 30 years.
In Neptune years, it’s less than a fifth of a year. ;)
In Neptune years, it’s less than a fifth of a year. ;)
Solar system observations are a explicitly included in the JWST's list of use cases, and observation time is allocated via the normal proposal process. I'm sure we'll see more pictures of solar system objects, even though obviously observations will always be science first, public relations second.
I love there are technical documents for each of the cameras:
https://www.stsci.edu/jwst/instrumentation/instruments
https://jwst-docs.stsci.edu/jwst-near-infrared-camera
(still trying to find the megapixels)
aha
https://www.stsci.edu/jwst/instrumentation/instruments
https://jwst-docs.stsci.edu/jwst-near-infrared-camera
(still trying to find the megapixels)
aha
Pixels 8 × 2040 × 2040 pixels
Pixel scale 0.031"/pixelAccessible link: https://archive.ph/1WCuG
Whenever I think of Neptune, I think of this image:
https://commons.wikimedia.org/wiki/File:Neptune_Full.jpg
This was taken in 1989 by Voyager 2, now 33 years ago. Voyager 2 remains the only spacecraft to have visited either of the ice giant planets.
https://commons.wikimedia.org/wiki/File:Neptune_Full.jpg
This was taken in 1989 by Voyager 2, now 33 years ago. Voyager 2 remains the only spacecraft to have visited either of the ice giant planets.
I hope to see pictures in real color later, if not with my own eyes. I'd be down for a 2 year round trip to Neptune.
2 year trip? At that speed, you’d zip by faster than the Griswold family vacationed at the Grand Canyon.
We should have something orbiting Neptune or at least on its way. I’ll be a very old man before anything could get there if we want to put something orbit (if I’m not already gone by then).
We should have something orbiting Neptune or at least on its way. I’ll be a very old man before anything could get there if we want to put something orbit (if I’m not already gone by then).
2years is a little optimistic.
I wonder how dark it would be out there if you saw it with your own eyes. I would guess it’s pretty dark.
I wonder how dark it would be out there if you saw it with your own eyes. I would guess it’s pretty dark.
The eyes have impressive dynamic range.
Moonlight is 250000x dimmer than sunlight, but you can still see things illuminated by moonlight once your eyes adjust.
Neptune is 29 AU from the Sun, so by inverse square law, the sunlight is 29^2=840x dimmer on Neptune than Earth. Visibility should be decent out there. Neptune will stand out pretty well against the perfect blackness of space.
Moonlight is 250000x dimmer than sunlight, but you can still see things illuminated by moonlight once your eyes adjust.
Neptune is 29 AU from the Sun, so by inverse square law, the sunlight is 29^2=840x dimmer on Neptune than Earth. Visibility should be decent out there. Neptune will stand out pretty well against the perfect blackness of space.
> perfect blackness of space.
Eyes dynamic range is good enough that the "background" isn't black either, consider the view of the night sky from outside a city.
Eyes dynamic range is good enough that the "background" isn't black either, consider the view of the night sky from outside a city.
I figure the diffuse glow up there is light being reflected around by the atmosphere, which isn’t present in most of the solar system.
Hmm, I've always figured it's a bit of eyes blurring "bright" lights (the stars you can see), and a bit that there are lots of really dim stars that you can't really see, but add in some light.
I don't actually know though.
I don't actually know though.
3 cheers for NASA!
I'm amazed by the below UI to show how Neptune's orbit at 30AU is proportionately farther from Jupiter (5.2 AU) than Jupyter is to Earth.
https://solarsystem.nasa.gov/planets/overview/
I'm amazed by the below UI to show how Neptune's orbit at 30AU is proportionately farther from Jupiter (5.2 AU) than Jupyter is to Earth.
https://solarsystem.nasa.gov/planets/overview/
Have they released any high resolution version? I tried finding on their website, but did not find anything.
Looks like the image in the article is a crop of this[1] view, which can be accessed in high res.
You can find all the JWT images in full res on here[2].
[1]: https://stsci-opo.org/STScI-01GCVNZ68YTC7FPTBSNA3QDGYW.png
[2]: https://webbtelescope.org/resource-gallery/images
You can find all the JWT images in full res on here[2].
[1]: https://stsci-opo.org/STScI-01GCVNZ68YTC7FPTBSNA3QDGYW.png
[2]: https://webbtelescope.org/resource-gallery/images
Thanks for the links! I checked out the source image and it still appears to be 80 pixels high in the "full resolution for display" image, same as the article's crop. There is a "close up" view which shows Neptune as 300px high, but I can't resolve any detail that isn't in the 80 pixel version. I think this is as detailed as it gets based on the apparent size of Neptune and JWST's angular resolution.
NIRCAM has a resolution of 0.031 arcsec per pixel, and Uranus is between 4.1 and 3.3 arcseconds wide as viewed from Earth, so it would only ever be between 132 and 106 pixels wide.
https://jwst-docs.stsci.edu/jwst-near-infrared-camera https://nssdc.gsfc.nasa.gov/planetary/factsheet/uranusfact.h...
If you want a higher resolution image, we'll either need a bigger telescope or a Uranus orbiter.
https://jwst-docs.stsci.edu/jwst-near-infrared-camera https://nssdc.gsfc.nasa.gov/planetary/factsheet/uranusfact.h...
If you want a higher resolution image, we'll either need a bigger telescope or a Uranus orbiter.
Holy cow the whole field is so amazing. Galaxies everywhere!
The historical context blows my mind, too.
The debate of "do other galaxies even exist?" wasn't definitively settled until 1923, 99 years ago, with Edwin Hubble's observations of Cepheids in Andromeda.
Now, you can just, like, look at them. (With a good telescope.) Every single place you look.
The debate of "do other galaxies even exist?" wasn't definitively settled until 1923, 99 years ago, with Edwin Hubble's observations of Cepheids in Andromeda.
Now, you can just, like, look at them. (With a good telescope.) Every single place you look.
Those are the first things I look for in space images. If you haven't seen it, go find the Webb deep field image that they released a month or two ago. It will blow your mind!
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Thanks a lot for the links!
I tried comparing this image with some from the Hubble and this one appears to be slightly sharper (not to mention much more detailed in terms of the atmosphere thanks to the infrared wavelengths). I don't think it gets too much higher-res than this without a probe getting close to the planet.
A google search indicates Neptune's largest apparent size in the sky is 2.4 arcseconds[0], and a commentor below suggests JWST's resolution is approximately 0.1 arcseconds (.068 at a wavelength of two microns[1], from some google searching), which would suggest a rough maximum resolution of about 35 pixels, while this image is 80. I'm unclear on the exact reasons for this difference.
[0] https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact....
[1] https://www.stsci.edu/files/live/sites/www/files/home/jwst/a...
A google search indicates Neptune's largest apparent size in the sky is 2.4 arcseconds[0], and a commentor below suggests JWST's resolution is approximately 0.1 arcseconds (.068 at a wavelength of two microns[1], from some google searching), which would suggest a rough maximum resolution of about 35 pixels, while this image is 80. I'm unclear on the exact reasons for this difference.
[0] https://nssdc.gsfc.nasa.gov/planetary/factsheet/neptunefact....
[1] https://www.stsci.edu/files/live/sites/www/files/home/jwst/a...
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This seems to be the highest-res closeup: https://webbtelescope.org/contents/media/images/2022/046/01G...
I think that's been upscaled, as it shows Neptune being over 300px in diameter. Unless I'm misinterpreting something (a distinct possibility), that would require an angular resolution of nearly 10x what the JWST is capable of. I don't know what kind of processing they applied to get it to that size but I can't resolve any detail in that closeup that isn't visible in the version where it's 80px. By my naive calculations (which I explain in another comment), Neptune should be about 30 pixels wide - is there anyone who can shed light on this mystery?
Also posted here: https://news.ycombinator.com/item?id=32926283
Thanks! I think we'll merge that thread hither since this one has the original source.
("Please submit the original source. If a post reports on something found on another site, submit the latter." - https://news.ycombinator.com/newsguidelines.html)
("Please submit the original source. If a post reports on something found on another site, submit the latter." - https://news.ycombinator.com/newsguidelines.html)
Have they released any images of the galactic center yet?
The galactic center image won't be as fancy, unfortunately. Resolution of Webb is far-far-far too low to see anything related to the black hole, the best we could do is enhance the view of the stars near Sgr A* [1].
1. https://www.eso.org/public/videos/eso0226a/
1. https://www.eso.org/public/videos/eso0226a/
Webb resolution is about 0.1 arc-seconds (wavelength dependent) [1].
Event Horizon Telescope (EHT) resolution is about 25 micro arc-seconds (wavelength dependent) [2].
So roughly speaking, since you cannot really compare the two, since they observe on quite different wavelengths, EHT has ~4000 times better resolution than Webb. Note that we don't speak about sensitivity here. ALMA array of radio telescopes has a collecting area of 7000 m2, while it is just one of many "nodes" of the EHT. Webb total collecting area is about 25 m2.
1. https://www.jwst.nasa.gov/content/about/faqs/faq.html#sharp
2. https://eventhorizontelescope.org/technology
So roughly speaking, since you cannot really compare the two, since they observe on quite different wavelengths, EHT has ~4000 times better resolution than Webb. Note that we don't speak about sensitivity here. ALMA array of radio telescopes has a collecting area of 7000 m2, while it is just one of many "nodes" of the EHT. Webb total collecting area is about 25 m2.
1. https://www.jwst.nasa.gov/content/about/faqs/faq.html#sharp
2. https://eventhorizontelescope.org/technology
Understood, but it still would be very interesting to see the area with JWST's full range of instruments.
I imagine that, along with any data for TRAPPIST, is on the [very long] list of things to do. Otherwise I'm sure it'd be posted here in no time
Love everything coming out of James Webb telescope
Anyone have a mirror on an actual website instead of the javascript application that all NASA.gov sites have become? Even with javascript enabled I can't get it to display anything other than a black screen.
And when I view source on that black screen it's all external JS calls. There are no img or href tags of HTML I can find that contain the images.
And when I view source on that black screen it's all external JS calls. There are no img or href tags of HTML I can find that contain the images.
It looks rather blurry and looks like it's captured with an Android camera (highly compressed jpg) although the file is png.
It's comments like this one that make me wonder whether it's made by a bot account which purpose it is to discredit Android and shape a negative reception, intended to work like anti advertisement. It's not just Android of course, it could happen for any topic.
More likely though that this user just does what any fanboy does - spew FUD on the "other side".
If you now further discuss Android camera quality, you'd just be off-topic.
More likely though that this user just does what any fanboy does - spew FUD on the "other side".
If you now further discuss Android camera quality, you'd just be off-topic.
I had just skimmed over the comment before reading yours and realizing that you are right.
can we get a noscript/basic (x)html link?
https://www.nasa.gov/sites/default/files/for_nasa.gov_imagea...
https://www.nasa.gov/sites/default/files/for_stsci_site_imag...
But really, it's a NASA site, it's probably safe w/o noscript (ie, disable restrictions for tab). Or, you can just individually enable permanently: nasa.gov; digitalgov.gov; foresee.com; gstatic.com; youtube.com (is what makes it work for me).
https://www.nasa.gov/sites/default/files/for_stsci_site_imag...
But really, it's a NASA site, it's probably safe w/o noscript (ie, disable restrictions for tab). Or, you can just individually enable permanently: nasa.gov; digitalgov.gov; foresee.com; gstatic.com; youtube.com (is what makes it work for me).
My browsers don't even have a javascript engine in the first place. It is not about security, but it's about those grotesquely and absurdely massive web engines, google financed blink/geeko and apple financed webkit (including the SDK).
Thx for the links though.
Thx for the links though.
PointyFluff(1)
Tomorrow (23rd) marks the 176th anniversary of the discovery of Neptune (~ 1.07 years on Neptune; 164.8 Earth years).
Johann Gottfried Galle an astronomer at the Berlin observatory found Neptune at the behest of Urbain Le Verrier who calculated its position by hypothesizing that some body must perturb Uranus orbit to explain the distinct deviation from the predicted motion by Newton's law of universal gravitation.
Le Verrier couldn't find a single French astronomer willing to take a look out at the sky after presenting his extensive calculations to the French Academy on 31 August. On 18 September he then wrote a letter to the German astronomer Galle at the Berlin observatory.
After receiving the letter 5 days later Galle immediately set up his telescope the same night and found a +8 mag star (within 1 degree of the Le Verrier's calculation) not listed on the official Prussian star chart. The next night he managed to measure the star itself moving by 4 arcseconds, finally confirming Le Verrier prediction of a new planet (and to this day last).
At ~30 AU (30x the distance sun-earth; Uranus being at ~20 AU) the discovery instantaneously made the solar system 1.5x bigger ;)