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Mars 360-degree panoramic view from Curiosity

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Re: Mars 360-degree panoramic view from Curiosity

#91

Post by wlievens »

raverbashing wrote: post #85
wlievens wrote: post #73

Earlier quoted context omitted.

> Let's reformulate the question: Why not keep the same enclosure, the same lens assembly, the same mechanical parts and simply swap the 2MP sensor for a 20MP sensor? You do know that a 20MP sensor is significantly (~10 times) larger than a 2MP sensor, right? So the mechanics would probably simply not fit.

Not necessarily, and this is important If they are of the same size, the pixel size - area - will be 10 times smaller for 10x more pixels (or a dimension - length x width - reduction of ~3.1x) Now, noise is bigger if the pixels are smaller. This is one of the ways to radiation harden components: make their features larger. I'm sure a small sensor like those in a compact camera would be subject to a lot of noise. Bigg…

Obviously I was assuming same pixel size. Sorry if that wasn't clear. You're correct about the noise, of course. Pixel size is at least as important as the number of pixels. That's why a 4 megapixel cell phone sensor ($15) is vastly inferior in image quality to a 2 megapixel industrial sensor that's ten times larger in area ($200).

I have a 24 megapixel sensor lying on my desk. Its pixels are 6 micron wide, which is large (but not huge), and the thing is about 4 cm by 3 cm in size. I don't know much about cameras but I think that's about the biggest you can fit in a typical consumer camera body.

Re: Mars 360-degree panoramic view from Curiosity

#92

Post by covalence »

arrrg wrote: post #61
ricardobeat wrote: post #55

Earlier quoted context omitted.

Repost from another thread: These are still from the navigation cameras. The main camera, not yet deployed, can take 1600x1200 full-color pictures and HD video at 10fps. There's actually two of it, so it can also make 3D images/video. Other features are wide/telephoto lens, panorama stitching and 8GB flash storage. Before complaining about resolution, this is like having a GoPro 3D on Mars, it has plenty of detail. O…

3D images are not possible since the two cameras have two different (fixed) focal lengths (for wide and tele shots). There were plans to add zoom lenses (which would make 3D images possible) but they couldn’t make it happen (mostly because of technical issues, it seems). (Hm, well actually, technically 3D images are possible, just not because there are two cameras. Since rocks tend to not move, Curiosity could just s…

I remember reading the zoom lenses weren't possible because of having to keep a lubricating fluid wet. This posed challenges (heating from mar's extreme cold, etc) so it was scrapped for the time.

Re: Mars 360-degree panoramic view from Curiosity

#93

Post by danielweber »

utoku wrote: post #47
uvdiv wrote: post #34

Earlier quoted context omitted.

The bandwidth to the orbiters is up to 2 Mbps, but because they're in low orbit they're only in sight 8 minutes per day. http://mars.jpl.nasa.gov/msl/mission/communicationwithearth/...

A bit of clarification, I think the orbiters are in sight of Earth for most of the day. It is Curiosity that is not in sight of the Orbiters, again because of their low orbit.

I'm not sure I understand. Gale Crater is pretty near the equator, so any equatorial satellite would pass quickly over it, but many many times per day.

Re: Mars 360-degree panoramic view from Curiosity

#94

Post by danielweber »

10098 wrote: post #40

Why is it all black-and-white? Is it because color cameras are too heavy/expensive to take or because color photography is for some reason impossible under those conditions?

Most (all?) of the pictures so far are from the hazard-cameras, which are used by Curiosity to make sure it doesn't fall off a cliff. (Or, less dramatically, to make sure it doesn't get stuck in some gravel.) The fact that the images are beautiful to us is just gravy.

Re: Mars 360-degree panoramic view from Curiosity

#95

Post by danielweber »

codehotter wrote: post #69

Here are some more pictures (including color) http://photojournal.jpl.nasa.gov/targetFamily/Mars I wonder what the sky of mars looks like. Can we see earth?

I found this http://www.msss.com/mars_images/moc/2003/05/22/

IIRC, Malin is the guy in charge of the cameras on this mission, too, so that's pretty much from the biggest expert on this topic.

EDIT Make sure you click on the full image -- that is amazingly beautiful!

Re: Mars 360-degree panoramic view from Curiosity

#96

Post by kibwen »

10098 wrote: post #39
eta_carinae wrote: post #26

I'm still trying to wrap my head around the fact that this piece of metal traveled 350 million miles through space and then landed on Mars.

Me too. I mean, look at this. The place looks like a desert on Earth, and yet its millions of miles away in space, on another planet. There's a certain feeling I experience when I look at those photos, like there is a vast, cold void inside of my chest. I felt something similar when I touched a meteorite for the first time. That rock came here from god knows where, probably it was floating around in space for many ma…

That rock came here from god knows where, probably it was floating around in space for many many years

Don't sell yourself short, you yourself were floating around in space for about ten billion years. Or at least, your constituent atoms were. :)

"We, who embody the local eyes and ears and thoughts & feelings of the cosmos, we’ve begun - at last - to wonder about our origins. Star stuff, contemplating the stars, organized collections of ten billion, billion, billion atoms, contemplating the evolution of matter, tracing that long path by which it arrived at consciousness here on the planet Earth and perhaps - throughout the cosmos." ~ Carl Sagan

Re: Mars 360-degree panoramic view from Curiosity

#98

Post by uvdiv »

danielweber wrote: post #93
utoku wrote: post #47

Earlier quoted context omitted.

A bit of clarification, I think the orbiters are in sight of Earth for most of the day. It is Curiosity that is not in sight of the Orbiters, again because of their low orbit.

I'm not sure I understand. Gale Crater is pretty near the equator, so any equatorial satellite would pass quickly over it, but many many times per day.

You answered your own question: both satellites are in polar orbits. They pass the equator many times a day, but at a different longitude each time.

Re: Mars 360-degree panoramic view from Curiosity

#99

Post by EternalFury »

wlievens wrote: post #73
EternalFury wrote: post #19

Earlier quoted context omitted.

You know, I didn't claim to understand the reasons behind the technical limitations, but the reactions of some of you are puzzling to me. We can go on and on about familiarity considerations, and planning considerations, and instrumentation considerations, and scientific concerns, etc. It all sounds like excuses after a bit. Let's reformulate the question: Why not keep the same enclosure, the same lens assembly, the…

> Let's reformulate the question: Why not keep the same enclosure, the same lens assembly, the same mechanical parts and simply swap the 2MP sensor for a 20MP sensor? You do know that a 20MP sensor is significantly (~10 times) larger than a 2MP sensor, right? So the mechanics would probably simply not fit.

Huh, no, not at all. The last 10 years have been spent increasing photosite density. Today's sensors can have 10-20 times the resolution, and be the same physical size or smaller. Today's sensors are also more reliable, less sensitive to dust and noise than sensors made 10 years ago.

Re: Mars 360-degree panoramic view from Curiosity

#100

Post by jonhendry »

xfhai wrote: post #83
jonhendry wrote: post #13

Earlier quoted context omitted.

" it takes a long time for data to travel from there to here" It doesn't take that long for it to travel, the data transmission rate is not very fast, and Curiosity doesn't have constant access to the Mars-orbiting satellites that relay the data to Earth. And besides that, its primary job is not taking pretty pictures.

If there is a satellite that orbits between Earth and Mars parallel to orbit of Mars, there could be better transmission.

The main thing is that the rover only has about 8 minutes a day to transmit to the orbiting satellites.

The optimal thing would be a satellite in areostationary orbit over Mars' equator such that it is always reachable by the lander.

Unfortunately such a satellite wouldn't be well-placed for many other potential landing sites.

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