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NASA’s Juno Spacecraft Sends First In-orbit View

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

#31

Post by kchoudhu »

peter303 wrote: post #30
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?

A late 2020s Europa mission has been given development money. It will take about five years to launch and another five to arrive. Europa has a large interior ocean under the ice and maybhave life. It has enough energy to keep water liquid at certain depths and drive life. A Europa mission might resemble Cassini and Juno: orbiting the main planet with frequent flybys of the moon. This requires less fuel and keeps the…

I seem to recall hearing that the funding for this was contingent on there being a lander as well?

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

#32

Post by jonknee »

jessriedel wrote: post #29
chaitanya wrote: post #21

Earlier quoted context omitted.

> At its closest approaches JunoCam could achieve 15 km/pixel resolution from 4300 km In comparison, the highest resolution photos of Pluto from New Horizons achieved 80 meters per pixel from a closest approach of 12500 km. Its amazing how good the camera was on New Horizons. https://www.nasa.gov/feature/new-horizons-best-close-up-of-p...

No doubt New Horizon's camera was phenomenal for the mission, but I'm actually not sure how good it was compared to something you could do with a terrestrial lens. (There are lots of compromises when you go to space.) Juno's camera is very modest by design: It's a wide-field of view and only a few megapixels, so basically a cell-phone camera.

> It's a wide-field of view and only a few megapixels, so basically a cell-phone camera.

It's not similar to a cell phone camera at all. Cell phone cameras are usually much higher resolution (current iPhone is 8 megapixels vs the 2 for Juno), but with a much smaller sensor (iPhone cam has a 1.5µm pixel size vs 7.4µm for Juno).

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

#33

Post by drzaiusapelord »

peter303 wrote: post #28
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?

SpaceX might launch a Mars lander during the 2018 low energy window. Though I am guessing more likely the 2020 window following that. NASA is fully cooperating with SpaceX by doing things like providing detailed data of previous Mars landings. NASA is SpaceX largest customer and financier. Many ex-NASA people workmat SpaceX. These data are public. But it helps to have good communication channels.

>SpaceX might launch a Mars lander during the 2018 low energy window.

Is this budgeted? Is it on a launch docket? Is there a rocket ready for it? Is the lander completed? 2018 is right around the corner and frankly I'm getting sick of "Spacex might" comments. There's a big difference between "might" and "do." When you see a mission on the NASA roster, its ready to go and unless there's some serious technical issue, it'll happen.

I'd like to see more "do" from SpaceX that isn't LEO flights and landing on barges.

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

#34

Post by drzaiusapelord »

cornholio wrote: post #7

I understand JunoCam is a public outreach tool. But if it provides much worse resolution than Hubble from inside Jupiter's orbit, it's basically useless even for that. I don't know if the cam is the problem or the transmission bandwidth, one thing is clear, when serios science starts there will be much less bandwidth available to send sharp and cool photos. That's what you get from a solar powered probe. We waste bil…

>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 missions.

Heck, Curiosity was launched just a few years ago and has 11lbs of plutonium powering its RTG. I hardly see a conspiracy here. Also RTGs add weight and cost to projects. If you don't need one, you probably shouldn't be using one - even ignoring their rarity. Missions like Juno get significant weight savings using solar.

>I don't know if the cam is the problem or the transmission bandwidth,

The quality of the photo has to do with the distance from Jupiter. It has nothing to do with "power." This is a spacecraft, not a gaming PC. Yes more power would mean a higher bitrate, but the bitrate it uses is good enough for the mission.

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

#35

Post by drzaiusapelord »

KnightOfWords wrote: post #10

Glad Juno has made it and appears to be working OK. Not the most amazing image, better ones are routinely taken by amateurs from earth, but the crescent can only be seen by going there as Jupiter lies outside our orbit. We'll see much closer views from Juno when it's moved to a closer orbit in October. I came across this on Reddit the other day, taken with a smartphone and 8" telescope: https://www.reddit.com/r/astro…

>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.

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

#36

Post by GonzoBytes »

I am astonished that humans can do this technology. Here I am looking at these pics a flying robot snapped from 4M+ km away from Jupiter?!

I wish they mark these pics with some pictographs regarding the scale of things. Like something comparing the orbital distances between the moons and Jupiter itself to that of Earth's orbital distance to the Sun or something. I cannot comprehend 4 million kilometers (which I know is Juno's distance to Jupiter, not the moons' orbital distance..). I have trouble wrapping my mind around just 4 km.

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

#37

Post by valarauca1 »

jonknee wrote: post #32
jessriedel wrote: post #29

Earlier quoted context omitted.

No doubt New Horizon's camera was phenomenal for the mission, but I'm actually not sure how good it was compared to something you could do with a terrestrial lens. (There are lots of compromises when you go to space.) Juno's camera is very modest by design: It's a wide-field of view and only a few megapixels, so basically a cell-phone camera.

> It's a wide-field of view and only a few megapixels, so basically a cell-phone camera. It's not similar to a cell phone camera at all. Cell phone cameras are usually much higher resolution (current iPhone is 8 megapixels vs the 2 for Juno), but with a much smaller sensor (iPhone cam has a 1.5µm pixel size vs 7.4µm for Juno).

Also light thresholds need to be taken into consideration. Jupiter is 5x[1] further from the Sun then Earth, so there is much less light to capture in an image.

[1] On average.

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

#38

Post by jessriedel »

jonknee wrote: post #32
jessriedel wrote: post #29

Earlier quoted context omitted.

No doubt New Horizon's camera was phenomenal for the mission, but I'm actually not sure how good it was compared to something you could do with a terrestrial lens. (There are lots of compromises when you go to space.) Juno's camera is very modest by design: It's a wide-field of view and only a few megapixels, so basically a cell-phone camera.

> It's a wide-field of view and only a few megapixels, so basically a cell-phone camera. It's not similar to a cell phone camera at all. Cell phone cameras are usually much higher resolution (current iPhone is 8 megapixels vs the 2 for Juno), but with a much smaller sensor (iPhone cam has a 1.5µm pixel size vs 7.4µm for Juno).

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".

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

#39

Post by flippyhead »

mixedmath wrote: post #8

> On later orbits, Juno will continue photographing the poles, but where else the camera will focus will be open to a popular vote by the public. NASA has been pretty active in public outreach. The article indicates that Juno takes something like 4 photos an hour. I wonder whether it will be 1 photo for the public to 3 photos for science, or totally different?

Yeah I hand't realized they did this. Pretty cool! I hope the boaty mcboatface people don't get wind of it. They might crash it into the big red spot!

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

#40

Post by ceejayoz »

GonzoBytes wrote: post #36

I am astonished that humans can do this technology. Here I am looking at these pics a flying robot snapped from 4M+ km away from Jupiter?! I wish they mark these pics with some pictographs regarding the scale of things. Like something comparing the orbital distances between the moons and Jupiter itself to that of Earth's orbital distance to the Sun or something. I cannot comprehend 4 million kilometers (which I know…

For scale, Io is almost the same distance from Jupiter as the Moon is from Earth - about 400,000 kilometers.

That's about 0.3% the distance of Earth to the Sun.

For a good sense of how enormous these differences are, try the video "Riding Light" - https://vimeo.com/117815404 - Jupiter shows up at the 43:10 mark (Earth's at 8:17, for size comparison).

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