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11 hours ago by ilyagr

Mars Reconnaissance Orbiter captured both Curiosity and Perseverance under their parachutes.

Aug 2012: https://en.wikipedia.org/wiki/File:MRO_sees_Curiosity_landin...

Yesterday: https://mars.nasa.gov/resources/25610/hirise-captured-persev...

4 hours ago by elihu

> As well as searching for signs of life, Perseverance's other key objective is to select and package rock samples that can be brought back to Earth laboratories by later missions.

That seems like a strange thing to have as a top priority. I would have thought the main thing was to examine the rocks there without having to bring them back to Earth. And later on, if you have a return-trip mission, you could probably just grab some convenient rocks then (though I suppose Perseverance will have a lot time to pick out only the best, most interesting rocks).

This also implies that a return-trip mission, if it happens, will be obligated to go to Perseverance's last location or else collecting the rocks was a waste. Which by then we might have more interesting places we'd rather land.

Are there any unmanned Earth-to-Mars-to-Earth missions planned, or is the current thinking that we'll be sending people there on the first return-trip mission?

2 hours ago by avhon1

The current plan is for a launch in 2026 to send a NASA-designed rocket, and a rover and an orbiter designed by ESA, to Mars. The rover will collect Perseverance's sample tubes and place them in the rocket, which will carry the tubes into Mars orbit. The orbiter will rendezvous, collect the sample tubes, and carry them back to Earth, landing in Utah in 2031.


Edit: to your other points, I've thought of some justifications for this architecture:

* The sample return mission will have very limited payload capacity, so the samples should be chosen on the basis of potential scientific value, and selected from a large land area. This can probably best be done with a multi-year rover mission equipped with the best scientific instruments and locomotion available.

* Perseverance's scientific instruments are useful for studying rocks that won't be sampled, so spending weeks or months ferrying samples to a return vehicle would be a sub-optimal use of its very valuable time.

* Mechanically interfacing (to transfer samples) with an orbital solid-fuel rocket is probably somewhat dangerous, so it's best for Perseverance if there's a less-valuable robot to do that.

* The return vehicle will probably be limited in where it can land, because it will have to land on ground that is suitable to launch from. It is unlikely to be landed anywhere close to a bunch of interesting rocks and formations.

* Science instruments, and the manipulators to use them, are heavy, power-hungry, and fragile. If the sample-collection rover doesn't have any, then it can be better-specialized for the task: faster, less fragile, able to traverse softer or more rugged ground. Traveling many tens of kilometers to collect samples may not be nearly as difficult for it as for any previous, science-burdened rover.

35 minutes ago by bryananderson

The first priority is to examine the rocks there, and Perseverance is stuffed to the gills with scientific instruments to do just that. But there's no way JPL can squeeze every kind of instrument from every kind of lab on Earth into one rover. If we want to get the most out of our trip to Jezero, we need a way to bring some rocks back here. And yes that does mean a second trip to the same place.

We could send human geologists to bring the samples back (though they could obviously pick up rocks themselves), but sending humans to Mars is both more expensive and more uncertain (it's been on the agenda many times but is always vulnerable to budget cuts due to the price tag and long duration of the program).

The only other way to do it is to send a robotic sample return mission. Why do it as two missions to the same place instead of one? Because a fully kitted-out scientific rover and an ascent stage together would be very heavy, requiring a larger rocket and probably a different entry, descent, and landing (EDL) mode. Mars EDL is hard: gravity too high for an easy powered descent like the Moon, atmosphere too thin for an easy aerobraked descent like Earth. The current "sky crane" EDL mode does not scale well to heavier vehicles. So we can't just send an ascent stage with Perseverance, and a near-future there-and-back-again mission couldn't feature a rover as capable as Perseverance. The best compromise is to find the most interesting samples with a top-of-the-line scientific rover, then send the ascent stage to get them later.

And yes, this uncrewed return mission is planned by NASA/JPL and ESA [1]. The current concept involves two launches: one sends a lander with an ascent stage (and possibly a small rover to fetch the samples, or Perseverance could do it--it depends how soon the ascent mission gets there) and the second sends an Earth return stage to bring the samples the rest of the way home.

[1] https://www.nasa.gov/press-release/nasa-moves-forward-with-c...

4 hours ago by eru

Some people are also thinking about making the first manned missions one-way.

6 hours ago by dawnerd

That link also doesn't prevent back button usage.

5 hours ago by sixothree

Why are two of those images apparently from the rover but not in the "raw image feed"?


2 hours ago by 8bitsrule

Those first couple (crappy) pix were made before the dust covers were blown off.

MRO was probably pretty busy at first, so they needed to keep image size small, just in case something died, or ...

Mars to Earth bandwidth is slower than your neighborhood IP.

" The data rate direct-to-Earth varies from about 500 bits per second to 32,000 bits per second (roughly half as fast as a standard home modem). The data rate to the Mars Reconnaissance Orbiter is selected automatically and continuously during communications and can be as high as 2 million bits per second."


10 hours ago by natch

The guy featured in the viral “7 minutes of Terror” video from Curiosity days, Adam Steltzner, gave a talk about those previous landings which is an absolute gem. Fantastic speaker. He goes through the technology in some detail at semi ELI5 level but enough to be good. Once he seems to be finished with the main topic, stick around for the personal and inspirational stories in the Q&A segment, well worth it.

If you haven’t seen 7 minutes of terror, it’s a must watch (a little on the laughable drama side but hey it’s deserved!), but no need to hunt it down because it’s included near the beginning of his talk in the link below.


11 hours ago by underseacables

If you have not watched the seven minutes of terror video produced by NASA, you absolutely must. It details exactly how they put these amazing machines on the surface of Mars.


8 hours ago by eCa

It's very interesting, but it suffers quite badly from the current trend of having too high volume on the background music while people are talking.

Edit: Well, this video is from 2012, so that trend has been going for a while..

12 hours ago by java-man

How come these images were made available to BBC, but not to the mission raw images web page [0]?

[0] https://mars.nasa.gov/mars2020/multimedia/raw-images/

11 hours ago by mzs

Because it's not a raw image instead is placed here: https://mars.nasa.gov/mars2020/multimedia/images/

11 hours ago by teraflop

The same images were posted to the official Twitter account: https://twitter.com/NASAPersevere

It's pretty normal for NASA/JPL to release the coolest-looking pictures as quickly as possible for PR, and then follow up with the comprehensive releases of raw data later, especially in the early stages of a mission. I don't see anything to indicate that BBC was given any kind of special treatment.

10 hours ago by java-man

I wish it were reverse: the raw images would appear first, followed by the processed media.

8 hours ago by giantrobot

They used to do it that way and wouldn't get much uptake in the media. Newspapers/websites want big colorful high resolution photos to use as header images for articles. The tiny grayscale HazCam images are technically interesting and useful but are visually boring to non-technical viewers.

11 hours ago by interestica

I was praising the big steps that NASA is making on this mission to really be publicly accessible... But they don't really have a unified communications plan. Images and information are spread out on various sites. The general public can't be expected to go searching. I was hoping the raw image site would be the primary location for all mission photos.

11 hours ago by undefined
11 hours ago by poopsmithe

Please please please tell me there was video captured from this angle!

8 hours ago by exporectomy

Yes and it will keep getting better! They've recorded audio as well as video of the descent from multiple cameras on both the rover and descent stage looking up and down at each other, the ground, and the parachute.

11 hours ago by soheil

If you read the Nasa press release where this image was taken from it does mention this is a frame from a video taken during descent.

7 hours ago by jazzyjackson

Should be out Monday, takes a while to transmit

10 hours ago by nerfhammer

> This high-resolution still image is part of a video taken by several cameras as NASA’s Perseverance rover touched down on Mars on Feb. 18, 2021.

They're probably still processing the whole video

4 hours ago by nerfhammer
6 hours ago by qwertox

Does anyone know why the two front wheels are turned inward?

4 hours ago by Nekhrimah

To fit [0] inside the circular shell of the heatshield.

[0] https://www.flickr.com/photos/24354425@N03/49953375668/

6 hours ago by 6nf

For clearance inside the spacecraft that contained the rover maybe?

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