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NASA’s Juno Spacecraft Sends First In-orbit View

nasa.gov

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Re: NASA’s Juno Spacecraft Sends First In-orbit View

#51

Post by jessriedel »

pwthornton wrote: post #45
jessriedel wrote: post #38

Earlier quoted context omitted.

Um, so the best cell phone camera on the market is within a factor of 2 in linear resolution? I think that qualifies as "basically".

It's the opposite of cellphone camera. It has low megapixels and a large sensor size. This will allow a lot of light onto the sensor and it won't suffer from the noisiness that high megapixels on a smaller sensor suffer from.

The point is that, on the spectrum of all imaging devices you might put on a satellite, both Juno and a cell phone camera are in the same rough neighborhood. They are dwarfed by telephoto lens, or 200 megapixel sensors. Remember especially that the topic we are discussing is the resolution (km/pixel) at a particular distance (see above), and for this the lens are much more important than the particular CCD chosen.

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#52

Post by Buttons840 »

ceejayoz wrote: post #47
jsingleton wrote: post #14

This is cool. Jupiter is easy to spot with the naked eye, as it's the second brightest object in the night sky after Venus (obviously, excluding the moon when lit). You can even see some of its moons with some basic optics. To think there is a probe there now is a pretty powerful image to inspire children. Something we couldn't do with the recent Pluto visit, as awesome as that was.

A six-inch scope in your backyard gets you this: https://www.flickr.com/photos/ceejayoz/26513799722/in/album-... My daughter's massively into space, and having a mid-size telescope (Celestron NexStar 6SE) has been truly wonderful. There's something really different about seeing it for yourself even if the picture isn't as good as one from a probe.

I was camping under a clear sky with friends and asked, "has anyone seen another planet with their own eyes?" and explained I meant seen any detail through a telescope. Nobody had. I resolved start some amature astronomy then.

Any suggestions on how to start?

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#53

Post by ceejayoz »

Buttons840 wrote: post #52
ceejayoz wrote: post #47

Earlier quoted context omitted.

A six-inch scope in your backyard gets you this: https://www.flickr.com/photos/ceejayoz/26513799722/in/album-... My daughter's massively into space, and having a mid-size telescope (Celestron NexStar 6SE) has been truly wonderful. There's something really different about seeing it for yourself even if the picture isn't as good as one from a probe.

I was camping under a clear sky with friends and asked, "has anyone seen another planet with their own eyes?" and explained I meant seen any detail through a telescope. Nobody had. I resolved start some amature astronomy then. Any suggestions on how to start?

The sidebar of https://www.reddit.com/r/astronomy has a bunch of useful articles on getting started. Just be warned that it's one of those hobbies that can get really expensive if you lack impulse control - "I need a new eyepiece! And a few more inches of aperture! And a better mount!" starts to pile up if you really enjoy it. :-D

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#54

Post by ridgeguy »

neals wrote: post #17

Are we going to get amazing Pluto-like images, like that chilling closeup? They really impressed me A LOT. Or is Jupiter close enough for us to already know enough about its surface?

We should get some extraordinary views of Jupiter's polar aurora activity. Also much higher resolution of gas dynamics phenomena because of Juno's perijove altitude of ~3,000 miles.

Doubt we'll see depth, unless it's through fortuitous breaks in high clouds. Other (non-imaging) instruments (microwave sounders, etc.) will tell us what's going on in Jupiter's interior. Metallic hydrogen? Rocky core? Juno may tell us.

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#55

Post by zodPod »

KnightOfWords wrote: post #44
drzaiusapelord wrote: post #35

Earlier quoted context omitted.

>Stacked 400 best in Autostackert This isn't a photo. It a photoshop fiction of 400 different photos blended together. There's a big difference between that and a single frame from a spacecraft. Comparing the two seems silly.

Hardly fictional, it's a pretty accurate representation of what Jupiter actually looks like. The main reason for using this technique is because our turbulent atmosphere blurs any image. Taking a video allows only a small percentage of the clearest frames to be combined. A spacecraft doesn't have this problem. The technique is called lucky imaging: https://en.wikipedia.org/wiki/Lucky_imaging Stacking improves signal-…

Really well said! Also, before reading your explanation, I was a little hazy on how the image stacking thing worked. Now I understand a lot better. It's like averaging to get all of the details to the forefront without the oddities!

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#56

Post by teh_klev »

cornholio wrote: post #49
drzaiusapelord wrote: post #34

Earlier quoted context omitted.

>gotten in their minds that RTG power is evil and dangerous RTG usage is curbed due to NASA's low supply of plutonium-238. Until more is made it makes sense to design for solar powered systems. Also these are risky missions with high pricetags and erring on the side of caution using well known technologies isn't some big conspiracy. Its to avoid high-profile fails. We can try new and risky stuff in lower profile miss…

Sorry, but you have no ideea what I'm talking about. You are probably to young to remember but going with RTG was immensely controversial when Cassini launched, which had an 135 kbps link. Juno, on the other hand has less than 1kbps, because it needs to carry a large solar array instead of an antenna and has much less power for the uplink - data rate is proportional to the square of transmitter power. Bad publicity i…

> Sorry, but you have no ideea what I'm talking about. You are probably to young to remember...

We don't speak to each other like that here, regardless of how right or wrong the previous poster's knowledge of the subject at hand.

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#57

Post by KnightOfWords »

zodPod wrote: post #55
KnightOfWords wrote: post #44

Earlier quoted context omitted.

Hardly fictional, it's a pretty accurate representation of what Jupiter actually looks like. The main reason for using this technique is because our turbulent atmosphere blurs any image. Taking a video allows only a small percentage of the clearest frames to be combined. A spacecraft doesn't have this problem. The technique is called lucky imaging: https://en.wikipedia.org/wiki/Lucky_imaging Stacking improves signal-…

Really well said! Also, before reading your explanation, I was a little hazy on how the image stacking thing worked. Now I understand a lot better. It's like averaging to get all of the details to the forefront without the oddities!

Glad you found it useful. If you haven't come across him before, this guy takes some of the best planetary images: http://www.damianpeach.com/index.htm

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#59

Post by lmm »

Buttons840 wrote: post #52
ceejayoz wrote: post #47

Earlier quoted context omitted.

A six-inch scope in your backyard gets you this: https://www.flickr.com/photos/ceejayoz/26513799722/in/album-... My daughter's massively into space, and having a mid-size telescope (Celestron NexStar 6SE) has been truly wonderful. There's something really different about seeing it for yourself even if the picture isn't as good as one from a probe.

I was camping under a clear sky with friends and asked, "has anyone seen another planet with their own eyes?" and explained I meant seen any detail through a telescope. Nobody had. I resolved start some amature astronomy then. Any suggestions on how to start?

See whether there's an observatory near you that has public viewing nights. I've seen Jupiter and a couple of its moons at the Hampstead Observatory. It's a much less frustrating experience than a backyard telescope when you're just getting started, IME, and you can meet some cool people too.

Re: NASA’s Juno Spacecraft Sends First In-orbit View

#60

Post by ianai »

sophacles wrote: post #41
kchoudhu wrote: post #26

I understand the importance of this mission, but after the Curiosity skycrane, the Pluto flyby and the Rosetta orbiter, I'm really jonesing for something cool . What else is in the pipeline?

This brings to mind a moment in the movie Apollo 13 , where one of the supporting characters says something to the effect of: "Leave it to NASA to make a moon landing boring". I think it says a lot of great things about NASA that people consider putting a satellite in orbit around Jupiter to be routine. Further great things from the fact that they really want NASA to stop being "boring" and invent some crazy new thin…

I propose the unit of militaries as a new standard measurement.
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