Hot answers tagged

66

Oh, I can answer this one. In my structural geology class, we breezed over a few paragraphs on the tectonics of impact craters, but it was in the textbook, and, being space-related, I was intrigued. One note: while most of the papers you'll find are on our own geology, the moon isn't that different compositionally from Earth at all, so I'm assuming the ...


48

Good question. I work on the Curiosity team, and I hear "geology" all the time, but never "areology." Too bad, really, since it's a great word, and I love the R/G/B Mars series.


23

A search on arXiv for "areology" produces no results. A search on ADS produces two results (one of which has the subtitle "The Geological Environment of Mars"). So the term is hardly ever used in titles of scientific publications. From google scholar, there seems to be a few publications about LIBS that use the term. In conclusion, it ...


22

It is actually too likely to find water there. There are 3 categories of Planetary Protection missions for a mission to Mars, IVa, IVb, and IVc. Curiosity meets the IVa criteria, a mission not intended to seek life on Mars. A IVb mission looks for life, and a IVc enters a special region which is: A special region is a region classified by COSPAR where ...


16

You are correct about some of the sources of moon quakes. NASA states there are are least four types of moon quakes: There are at least four different kinds of moonquakes: (1) deep moonquakes about 700 km below the surface, probably caused by tides; (2) vibrations from the impact of meteorites; (3) thermal quakes caused by the expansion of the frigid ...


16

The traditional method (as used in the Apollo project) was to crash used SIVB stages into the Moon.


12

Based on this article, 39A is just concrete on top of sand. That does seem a little ridiculous though. The pumps piled up another portion of the dredged sand on the launch pad, creating a flat-topped pyramid of sand and shell 80 feet (24.4 meters) high. During the process, draglines, bulldozers and other earth-moving equipment molded the mound into the ...


12

It's actually a rebound effect that occurs with an impact forming a large crater. https://www.lpi.usra.edu/education/explore/shaping_the_planets/impact-cratering/ explains: Central peaks – Peaks formed in the central area of the floor of a large crater. For larger craters (typically a few tens of kilometers in diameter) the excavated crater becomes so ...


12

It might help to compare the crater formation to a drop impact: It seems that rock can behave like a viscous mass if you hit it fast enough.


11

The dark and large areas are solidified lava beds from earlier periods of Lunar evolution, when it was still volcanically active. Notice that they might be somewhat less covered by still visible impact craters than on average the lighter areas are, as then still liquid lava would completely cover any traces of impacts from the early Lunar history. As the ...


11

It does not appear to be a term in common usage in formal scientific settings. Wikipedia suggests that geology is a term generalised to all planets and areology is mainly used in popular media and science fiction. "The geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure,...


10

The rover already has a core drill for this purpose: it drills through the top layers and exposes the rock underneath. The big advantage of a drill over a shovel is that a drill can go through (most) rock types, whereas a shovel can only scrape off loose rubble. A shovel is an imprecise instrument: you run a straight edge over the soil. The depth of that ...


10

Edit - added more detail on the specific geological interests per the question revision Selection Process This letter to Dr Michael Meyer, lead scientist for the Mars Exploration Program, gives a synopsis of the assessments and findings at the February 2017 workshop. The workshop aimed to narrow the shortlist of landing site candidates from 8 to 3. Five ...


9

This paper reports SHARAD observations of this site, and also references previous publications based on an earlier radar instrument MARSIS. It's complicated and the data seems to be ambiguous, but the bottom line appears to be that it isn't a large lake of solid ice. It might be broken up volcanic rock with ice filling the spaces, or it might just be rock. ...


9

We don't really know. A study from 2012 suggests that lichens and cyanobacteria could indeed survive the "obvious" perils of Mars, including radiation, low pressure, and temperatures dropping as low as $-50°\text{C}$. In 2012 the Planetary Society reports a two-stage experiment performed at the German Aerospace Center, in which (1) organisms were ...


9

That's almost certainly ChemCam's laser vaporizing some rock for its spectrometer. You can see similar white spots in this video: The laser fires in short pulses 10 times a second, and there's gaps between the video frames captured by MAHLI. The two are not synchronized and only sometimes align, allowing MAHLI to see the ...


8

There are several causes: delays due to operational problems. When I last left the rover back in September, it had just climbed onto Vera Rubin Ridge. Since then, it has slowly maneuvered southish atop the ridge, encountering colorful rocks. Progress has occasionally been interrupted by various issues (uplink failures, arm faults, short drives, et ...


8

Let's examine what's already on InSight: A seismometer (SEIS). It's so sensitive that it is expected to be able to sense windstorms, dust devils, and the tidal forces of Mars' moon. To isolate the sensors from motions of the main body of InSight, SEIS is in its own pod that will be placed a few feet away by a robotic arm, and attached by an umbilical. ...


7

As far as I can tell, the 50 figure is somewhat erroneous/only approximate which is (understandably) caused by the confusing way the proposed landing site list changed during the selection process. I've attempted to collate the information from the Landing Site Workshops overview which has all the presentations and announcements from the entire process. In ...


7

A strong candidate for largest river on Mars that I have found is the Kasei Valles region of Mars. According to the Wikipedia entry, this area is home to a geological feature similar to our famous Grand Canyon. . . except for one major difference. This guy is 300 miles wide at maximum instead of 18 miles. Source: Areong via Wikipedia, CC BY-SA 4.0 General ...


7

I suggest that the Valles Marineris–Chryse Planitia complex is the largest former Martian river system. Valles Marineris has many features that appear to have been created by water flow and the outflow channels leading from it to the former oceana,b,c,d,e,f in Chryse Planitia are clearly visible and bear many features in common with river systems on Earth. ...


7

From Mars Fact Sheet: hydrogen (H), carbon (C), nitrogen (N), oxygen (O), argon (Ar), neon (Ne), krypton (Kr), xenon (Xe). From Inorganic analysis of martian surface samples at the viking landing sites: (DOI: 10.1126/science.194.4271.1283) silicon (Si), iron (Fe), magnesium (Mg), aluminum (Al), sulfur (S), calcium (Ca), titanium (Ti), strontium (Sr),...


6

If HP³ detects water, it will be done indirectly through thermal conductivity or specific heat. It has no sensor that directly detects water, such as a chromatograph or mass spectrometer (nor room for such). The paper you cite above was published in 2011. It was written before HP³ was chosen in 2012 for InSight: The mole design goes back to the PLUTO ...


6

Have the rovers on Mars encountered anything unrecognizable to geologists? Yes, sort-of: These are similar to structures on Earth that are produced by life, so they have people scratching their heads! See my Earthscience SE question What are Ordovican trace fossils, and what do they look like? (I've just added a bounty there.) There are some unusual ...


5

Have a look at this page, with links to MSL Landing site Workshops. It has the 33 landing sites list of the first workshop. There's also a link to the presentations of the second workshop. The "Overview of Process and Goals" presentation by John Grant contains also the Workshop agenda, where you find the 51 sites list. You might also want to check this ...


5

I did further processing on a 80x40 sub-image covering the anomalous pixels: All images are seen at a browser based 8X zoom scale (FF will dither it smoothly, which makes the lines less sharp, but almost as clear). The information in pixel x/y, RGB & 'gray scale difference' between that pixel and the surrounding pixels was calculated and shown in a ...


5

Would not a circular saw on one arm and a trowel on another on the Mars 2020 rover add scientific value? Every different type of thing you can do has "scientific value", even if it proves that it's not a good idea something is learned; it just that it's less expensive to learn that on Earth. A circular saw on a telescopic arm with the ability to cut into ...


5

At an elemental level, Mars will contain at least to some degree all of the elements found on Earth, albeit at different proportions. Mars is primarily igneous. Thus any kind of sedimentary and metamorphose minerals will not be found in any great abundance. Thus marble, slate, quartz, flint, clay, limestone, and others will be rare, if found at all. These ...


Only top voted, non community-wiki answers of a minimum length are eligible