APOD: Valles Marineris: The Grand Canyon... (2020 May 24)

[APOD Robot]

Valles Marineris: The Grand Canyon of Mars

Explanation: The largest canyon in the Solar System cuts a wide swath across the face of Mars. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris remains unknown, although a leading hypothesis holds that it started as a crack billions of years ago as the planet cooled. Several geologic processes have been identified in the canyon. The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s.

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[MarkBour]

"The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s".
I think it would be fascinating to watch a detailed description of the process of putting together that mosaic.

It's certainly nice to be able to see this astonishing view without having to spend months in a small capsule to go look at it. But if you like that sort of thing ... https://www.zdnet.com/article/nasa-want ... -missions/

[orin stepanek]

So big that the best view is from afar!

[NCTom]

That was some crack considering after a couple of billion years of dust storms the thing is still 8 kilometers deep!

[rwlott]

The canyon is interesting, but I'm curious about the three brown "sores" on the image left. What are they and by what processes were they created?

[neufer]

Mars: 100 Piece XL Jigsaw Puzzle

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"The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s".

I think it would be fascinating to watch a detailed description of the process of putting together that mosaic.

It's certainly nice to be able to see this astonishing view without having to spend months in a small capsule to go look at it. But if you like that sort of thing ... https://www.zdnet.com/article/nasa-want ... -missions/

[Ann]

The canyon is interesting, but I'm curious about the three brown "sores" on the image left. What are they and by what processes were they created?

They are volcanoes.

The Tharsis bulge with Valles Marineris and three volcanoes in a row, Ascraeus Mons, Pavonis Mons and Arsia Mons. NASA / JPL-Caltech / Arizona State University - JMARS

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Wikipedia wrote:

The western hemisphere of Mars is dominated by a massive volcano-tectonic complex known as the Tharsis region or the Tharsis bulge. This immense, elevated structure is thousands of kilometers in diameter and covers up to 25% of the planet's surface. Averaging 7–10 km above datum (Martian "sea" level), Tharsis contains the highest elevations on the planet. Three enormous volcanoes, Ascraeus Mons, Pavonis Mons, and Arsia Mons (collectively known as the Tharsis Montes), sit aligned northeast–southwest along the crest of the bulge. The vast Alba Mons (formerly Alba Patera) occupies the northern part of the region. The huge shield volcano Olympus Mons lies off the main bulge, at the western edge of the province.

Built up by countless generations of lava flows and ash, the Tharsis bulge contains some of the youngest lava flows on Mars, but the bulge itself is believed to be very ancient. Geologic evidence indicates that most of the mass of Tharsis was in place by the end of the Noachian Period, about 3.7 billion years ago. Tharsis is so massive that it has placed tremendous stresses on the planet's lithosphere, generating immense extensional fractures (grabens and rift valleys) that extend halfway around the planet. The mass of Tharsis could have even altered the orientation of Mars' rotational axis, causing climate changes.

So if Valles Marineris is a humongous rift valley, then maybe it cracked open because of the enormous mass of the Tharsis province.

Ann

[johnnydeep]

marsglobe_viking_960.jpg

So big that the best view is from afar!

Perhaps, but it would sure be sweet to be able to fly along and within it in a helicopter!

[johnnydeep]

That was some crack considering after a couple of billion years of dust storms the thing is still 8 kilometers deep!

Hmm, that's an interesting thought. I wonder if the canyon really does have a very thick layer of dust at its bottom...

[Chris Peterson]

That was some crack considering after a couple of billion years of dust storms the thing is still 8 kilometers deep!

Hmm, that an interesting thought. I wonder if the canyon really does have a very thick layer of dust at its bottom...

The wind on Mars removes dust as easily as it deposits it. Most of the Martian landscape is defined by bare, exposed rock, not deep dust.

[Z00mer]

It seems to me the dust could blow in and out, but sand would be more likely to accumutate way down deep.

[Z00mer]

Considering the low atmospheric pressure on Mars would that pressure differential 8 kilometers down be enough to attract habitation there, at least in the early stages?

[Jerome68]

The problem is not the pressure I guess, from my understanding the biggest impediment is the lack of Magnetic Field that refuse the very energetic particles from the sun. Without that protection, no cell can grow because it DNA it get destroyed automatically on the surface the moment the sun rises.

Any kind of habitation will require protection from sun, and a bit of pressurization to have a normal life.

[ta152h0]

Boy, it would be fun to throw a paper airplane off the top of that canyon! pass the ice cold one.

[Jerome68]

Boy, it would be fun to throw a paper airplane off the top of that canyon! pass the ice cold one.

haha indeed, and not forgetting about the amount of red dust it will get... so you will have an iced red painted paper airplane xD

[TheZuke!]

Perhaps, but it would sure be sweet to be able to fly along and within it in a helicopter!

Not accounting for conventional engines not working in the thin atmosphere, I wonder just how large (long, wide) the rotary wings would need to be for a "helicopter" ( one or two human occupants) to provide lift!

[neufer]

Perhaps, but it would sure be sweet to be able to fly along and within it in a helicopter!

Not accounting for conventional engines not working in the thin atmosphere, I wonder just how large (long, wide) the rotary wings would need to be for a "helicopter" ( one or two human occupants) to provide lift!

Ingenuity (also known as the Mars Helicopter) weighs just 1.8 kg ...
but has 1.2 m diameter rotors rotating at near max (~ 0.7 Mach) blade tip speed.

A flotilla of a few hundred Ingenuities in conjunction with a high-altitude balloon might work.

[TheZuke!]

Instead of Ingenuity, I think they should have named it AMEE (Autonomous Mapping Evaluation and Evasion) after the robotic dog in the movie "Red Planet" which had a helicopter type drone which it would launch and recall for increased surveillance.
B^)

[Jerome68]

xD, that is a good one. But now seriously, there are many ways to explore Mars before going. The rovers have been great though, but as you mention, using Drones for example, super cheap to create, much faster, no problems with the topology of the land is exploring and less weight.