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First full-resolution images of the Martian surface

nasa.gov

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Re: First full-resolution images of the Martian surface

#71

Post by mturmon »

ballooney wrote: post #45
pyoung wrote: post #17

Earlier quoted context omitted.

Yup, this mission has been in the works for ~10 years so I would imagine that they chose the specific sensor at least 6-7 years ago. Also NASA is notoriously risk averse (for good reason). Apparently it is very common for them to rely on old but proven technology. Some of this has to do with risk aversion, but I imagine some of it also has to do with budget. It pains me to think what NASA could be doing with 10x more…

>It pains me to think what NASA could be doing with 10x more money. Me too, but pretty much it all ends going to Lockheed anyway whether it comes via the DoD or Nasa. I don't mean that conspiratorially either, even JPL people joke that JPL stands for "Just Procure Lockheed". The subcontractors rarely get mentioned in Nasa PR, but Nasa is really a whole bunch of different project offices spread over a few campuses wit…

The Just Procure Lockheed thing is never heard around JPL. I'm not doubting that someone said it, some time, but that's not the Lab mindset at all. If you want to make an institutional characterization about JPL, you could say "hardware-centric", or "arrogant", or "cocky", but not "Just Procure Lockheed".

I agree that there are a lot of subs, but JPL and other centers have a very strong interest in maintaining a core capability in strategic areas. Launch vehicles: not a core capability, and commercially available -- subcontract these. Planetary robotics and deep space communication: core capabilities -- keep in-house.

Also, your comment underestimates how much distributed expertise is required to develop and integrate a set of instruments like this, and to get it to Mars. It's not practical for all that expertise to be NASA only.

Re: First full-resolution images of the Martian surface

#72

Post by jcarreiro »

jakeonthemove wrote: post #59
seanalltogether wrote: post #57

Earlier quoted context omitted.

I wonder if eating away at the current atmosphere of venus is more or less technically challenging then the task of creating an atmosphere from scratch on Mars. Since Venus also has way more mass, I'm guessing humans would feel more comfortable there then on Mars.

My thoughts exactly - Venus seems like a better place to start interplanetary exploration with - as I understand, if you could cool it down to an acceptable temperature, you could walk on the surface with just a breathing apparatus, right?

  > as I understand, if you could cool it down to an
  > acceptable temperature, you could walk on the surface
  > with just a breathing apparatus, right?
Sadly, probably not. Cooling it down is already a very tall order, and even then, you would need to find a way to remove most of the atmosphere in order to reduce the pressure (~90 atm at the surface).

Mars is a much better bet for human habitation in the short term. Chemically, it has all the ingredients we need to support human life. And it is much easier to build structures that can withstand the thin atmosphere (0.6 kPa) and relatively tame temperature range (-87 C to 63 C, all figures according to Wikipedia) than to build something that can survive the 9 MPa and 450 C on the surface on Venus.

Re: First full-resolution images of the Martian surface

#73

Post by jonesbb »

tomkit wrote: post #56

Random tangent, but I wonder what procedures NASA goES through to scrub all living organisms from the robot itself if one of their aims is to see if they can detect life on the martian planet.

NASA adheres to planetary protection procedures and requirements. For MSL...

"Selected components were heated to temperatures ranging from 110 to 146 degrees Celsius (230 to 295 degrees Fahrenheit) for durations up to 144 hours. Tools and other equipment that could come into contact with rover hardware were also cleaned routinely with alcohol wipes."

More details here: http://mars.jpl.nasa.gov/msl/news/pdfs/MSL_Plan_Prot_FactShe...

Re: First full-resolution images of the Martian surface

#74

Post by jcarreiro »

TomGullen wrote: post #31

I absolutely love this stuff. The photos to me are strangely eerie, and even perhaps a little sinister. I have trouble comprehending the size of other planets, photos like these make me feel uneasy (in an exciting way) because they are strikingly similar to landscapes we might find here on earth - yet it's a completely different planet! I'm no longer looking at mars as a red circle as shown in textbooks, but now as v…

  > I have trouble comprehending the size of other planets
I'm not sure this will help, but the surface area of Mars is about 1/3 that of Earth. Given that roughly 2/3 of the Earth's surface is covered by water, one can think of the surface of Mars as being roughly equivalent in area to the entire land area of the Earth.

Re: First full-resolution images of the Martian surface

#75

Post by powerslave12r »

jws wrote: post #69
jakeonthemove wrote: post #59

Earlier quoted context omitted.

My thoughts exactly - Venus seems like a better place to start interplanetary exploration with - as I understand, if you could cool it down to an acceptable temperature, you could walk on the surface with just a breathing apparatus, right?

It has 92 times Earth's atmospheric pressure at the surface. This would be a bad idea. It would be like being 900 meters deep in the ocean on Earth. 150 meters is about the limit for humans before High Pressure Nervous Syndrome stops the fun. But around 50km above the surface of Venus, the temperatures are nice, and the pressure is 1 earth atmosphere. You just have to to stay up there.

Perfect. Given Venus's gravity is 0.904g, we could work something out in a few years.

Re: First full-resolution images of the Martian surface

#77

Post by jcarreiro »

jws wrote: post #69
jakeonthemove wrote: post #59

Earlier quoted context omitted.

My thoughts exactly - Venus seems like a better place to start interplanetary exploration with - as I understand, if you could cool it down to an acceptable temperature, you could walk on the surface with just a breathing apparatus, right?

It has 92 times Earth's atmospheric pressure at the surface. This would be a bad idea. It would be like being 900 meters deep in the ocean on Earth. 150 meters is about the limit for humans before High Pressure Nervous Syndrome stops the fun. But around 50km above the surface of Venus, the temperatures are nice, and the pressure is 1 earth atmosphere. You just have to to stay up there.

  > around 50km above the surface of Venus, the temperatures
  > are nice, and the pressure is 1 earth atmosphere. You just
  > have to to stay up there.
Lando Calrissian just called. He wants his Cloud City back. :)

Re: First full-resolution images of the Martian surface

#78

Post by jcarreiro »

skeletonjelly wrote: post #67
bialecki wrote: post #63

Random question: Is it silent on Mars? I'm looking at this picture and can't help but wonder what it sounds like. Just curious if Martian weather tends to be windy or calm.

They didn't pack a microphone! Bastards! :P Considering the propensity for dust storms I'm going to say windy. But the atmosphere is thinner, so this makes it harder to hear? Or quieter?

  > But the atmosphere is thinner, so this makes it harder to
  > hear? Or quieter?
Sound intensity for a plane wave is given by the equation $I = \xi^2 \omega^2 c \rho$. Here $\xi$ is the particle displacement (the amplitude of our wave), $\omega$ is the angular frequency, and $c \rho$, typically called $Z$, is the characteristic acoustic impedance, where $c$ is the speed of sound and $\rho$ is the density of the medium.

Given that the speed of sound is roughly independent of pressure, and keeping all other variables equal, as $\rho$ decreases, $I$ also decreases. So yes, on Mars, sounds are much quieter.

Sources: http://physics.stackexchange.com/questions/672/what-is-the-r...

http://en.wikipedia.org/wiki/Sound_intensity

Re: First full-resolution images of the Martian surface

#79

Post by JunkDNA »

outside1234 wrote: post #2

i hate to be critical of an image sent from millions of miles away but I have an honest question: Why do images from landers like this always look like there were taken from a iPhone 1's camera?

This is a great, detailed description about what it's like to do image processing from a space probe on Mars

http://cdn.oreilly.com/radar/2012/08/Beautiful_Data_Chapter3...

It's from O'Reilly's "Beautiful Data", made available free in honor of the current mars mission.

The short answer (covered in that document) is actually that the sensors have to be hardened for space use and are not consumer grade. They are incredibly expensive to produce.

Re: First full-resolution images of the Martian surface

#80

Post by jcarreiro »

bialecki wrote: post #63

Random question: Is it silent on Mars? I'm looking at this picture and can't help but wonder what it sounds like. Just curious if Martian weather tends to be windy or calm.

  > Is it silent on Mars?
Good question! No, it is not. See http://sprg.ssl.berkeley.edu/marsmic/sound.html for an experiment, carried on the Mars Polar Lander, which would have attempted to record the sounds of Mars. Sadly the instrument was lost along with MPL.

  > Just curious if Martian weather tends to be windy or calm
Another good question. Mars is quite windy. I don't have a reference handy, but Spirit and Opportunity recorded numerous dust devils on the Martian surface. IIRC, they sometimes saw more than one a day!
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