Tag: Mars

Ingenuity’s next flight and the plans beyond

1:19 pm

Overview map
Click for interactive map.

In an update posted today written by Ingenuity pilot Martin Cacan, he outlined the engineering team’s goal for the Mars’ helicopter’s next flight, its nineteenth.

This flight, which will take place no earlier than Friday, Jan. 7, takes the scout vehicle out of the South Séítah basin, across the dividing ridge, and up onto the main plateau. The precise landing target for Flight 19 is near the landing site of Flight 8. Images taken during Flight 9 by the rotorcraft’s high-resolution Return-To-Earth (RTE) camera were used to select a safe landing zone.

…Spanning 207 feet (63 meters), this flight will last about 100 seconds at a groundspeed of 2.2 mph (1 meter per second) and altitude of 33 feet (10 meters) while taking 9 new RTE images. The final act of the flight is to turn nearly 180 degrees to flip the RTE camera to a forward-facing orientation for future flights toward the river delta. [emphasis mine]

The green line in the map to the right indicates the exact path, going about 207 feet to the northeast. The red dot marks the location of Perseverance on December 8, 2021, the last time the Perseverance science team updated their map showing the rover’s travels.

The highlighted words are the most important. Cacan also said this in his update:

The current mission goal is to reach the Jezero river delta to aid the Perseverance rover in path planning and scientific discovery.

Assuming the helicopter continues to function correctly, their next flights will apparently be aimed towards the delta. Whether that path will follow the planned route marked by the dashed yellow line, or cut straight across, is not clear. If the latter, that implies they have revised Perseverance’s planned route so that it also cuts straight across from about the point of Ingenuity’s next landing site.

More likely Cacan was not speaking literally, and that the route Ingenuity will take to the delta will follow the planned route, around that crater to the northeast.

Leave a comment

Ice canyons at the Martian north pole

1:46 pm

Ice canyons at the Martian north pole
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on July 24, 2021 by the high resolution camera of Mars Reconnaissance Orbiter (MRO) and shows one small portion of the edge of Mars’ north pole ice cap.

The many layers in that ice cap are clearly evident, with some darker because they were probably laid down at a time when the Martian atmosphere was more filled with volcanic ash. According to the presently accepted theory, the layers show the cyclical climate patterns of Mars, caused by the large shifts in its obliquity, or the tilt of the planet along its rotational axis, ranging from 11 to 60 degrees. Presently Mars is tilted 25 degrees, similar to Earth’s 23 degrees. The two extremes cause the planet’s water ice to shift back and forth from the mid-latitudes to the poles, causing the layers.

The height of this layered cliff face is probably about 1,500 feet, though that is a very rough estimate. Notice also that this image shows an ice canyon running from the left to the right and flowing into a much larger ice canyon to the right. The top cliff is probably about a third the height of the bottom cliff.

The overview map below shows gives the context, not only in place but also in time.
» Read more

One comment

The badlands on the floor of Valles Marineris

1:03 pm

The badlands on the floor of Valles Marineris
Click for full image.

Cool image time! The recent discovery that there might be a near surface reservoir of ice on the floor the canyon Valles Marineris, near the Martian equator, immediately brought this location to the forefront as a possible site for establishing colonies. The weather will be less harsh than higher latitudes, the low elevation means a thicker atmosphere, and the terrain will be more appealing than the boring flat northern lowlands.

The picture to the right, cropped and reduced to post here, illustrates however the likely difficulties of landing and living on the floor of Valles Marineris. Taken on July 26, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), the photo shows just one small area of the floor of Ius Chasm, the western part of Valles Marineris and about 300 miles to the east of that water reserve.

In this one picture we can see trapped sand dunes in hollows, eroded depressions, mottled terrain resembling stucco, and innumerable cliffs and sinks and plateaus. For the first manned spacecraft to land on Mars, this is not a good first choice. Even later, when the first bases have been built, this terrain would still be forbidding for the early colonists to land in and traverse.

The overview map below shows exactly where this picture is relative to the rest of the Valles Marineris.
» Read more

16 comments

Slope streaks in frozen lava flows on Mars

12:30 pm

Slope streaks on frozen lava
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on June 5, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a ridgeline at the base of the giant volcano Pavonis Mons, with slope streaks on ridge’s north and south sides.

Slope streaks are a mysterious phenomenon unique to Mars. While they resemble an avalanche, they do not change the topography of the surface at all. They appear to occur randomly year round, fading slowly with time. Also, while most are dark, scientists have also spotted bright slope streaks as well.

Slope streaks also only appear on surfaces covered with a layer of fine dust, something that is obviously the case in the cool image to the right. There is so much dust on the surface here that bedrock only appears at the top of the ridge, peeking out in only a few places.

The location of this image, as shown in the overview map below, adds some additional details.
» Read more

One comment

The barren rocky terrain in the mountains of Gale Crater

9:52 am

Curiosity's view looking south towards Mt Sharp, Sol 3333, December 21, 2021
Click for full resolution image. Original photos can be found here, here, here, here, and here.

Overview map
Click for interactive map.

Cool image time! Curiosity yesterday used its navigation cameras to take a panorama of the view inside Maria Gordon Notch. The mosaic above, created from five images taken by the right navigation camera, shows the view looking south and uphill towards Mount Sharp. The heights of the nearest four hills are likely ranging from 30 to 100 feet.

The red dotted line indicates the planned route out of Gordon Notch and up onto the Greenheugh Pediment. If you click on the panorama to look at the full resolution version, you will see that the exit route looks extemely rough, possibly too rough for Curiosity to handle. How the science team handles this issue will be fascinating to watch in the coming weeks.

The map to the right gives us an overview. The white line is Curiosity’s actual travels. The red dotted line marks the planned route. The yellow lines indicate the area covered by the panorama above.

The most striking feature of this Martian terrain is its stark barrenness. All one can see in all directions are rocks and inanimate geology. There is no life, none at all. On Earth it is practically impossible to find any mountainous spot as barren as this, even in the most extreme and hostile environments.

As I’ve said before, Mars is strange, Mars is wonderful, and above all, Mars is alien.

Leave a comment

Curiosity: Through the notch and looking back

11:46 am

Looking back at the entrance to Gordon Notch
Click for full image.

The Mars rover Curiosity has now climbed up into Maria Gordon Notch. The image to the right, reduced to post here, was taken by the rover’s left navigation camera and looks back at the entrance to the notch, with the floor and rim of Gale Crater beyond. The crater floor is about 1,700 feet below and the rim is about 30 miles away.

The red dotted line indicates the path Curiosity took after entering the notch, traveling about 80 feet to the southeast. The rover will continue south inside the notch for another 800 feet or so and then turn west, climbing out of the notch and up onto the Greenheugh Pediment and continuing west until it gets to the base of Gediz Vallis Ridge, a ridge that had been in prominent view about a year ago when the rover was north of it but lower down the mountain. (See the panorama in this February 2021 post.)

Below is another picture from a day earlier, this time taken by the rover’s high resolution mast camera. I think it looks up at the top of the western cliff, but now looks at that cliff after having gone past it slightly.
» Read more

4 comments

Ingenuity successfully completes its 18th flight

1:26 pm

According to a JPL Twitter post today, on December 15th Ingenuity successfully completed its 18th flight, flying 754 feet for just over two minutes.

The plan had been to continue north to cross the rough Seitah region as the helicopter heads back to the spot where Perseverance initially dropped it. Though at this moment no specific information about the flight’s direction or landing place have been revealed, its success suggests it went exactly as planned.

One comment

Perseverance scientists: First volcanics then water in Jezero Crater

9:45 am

On December 15th the Perseverance science team presented a summary of the rover’s first nine months exploring the floor of Jezero Crater, finding evidence first of volcanic lava activity followed by several periods where water covered the these same rocks.

“These rocks that we originally thought might be sedimentary rocks, these are in fact igneous [volcanic] rocks,” said Kelsey Moore at the California Institute of Technology (Caltech). “And even more excitingly, they’re not just igneous rocks – there’s more history to the story.”

The analysis of the rocks’ compositions revealed minerals that are generally produced by interactions between water and rock, as well as traces of two different salts that were probably left behind as salty water flowed through the cracks and pores in the volcanic rock.

The variety of minerals indicates that these rocks were probably underwater at least twice. “Two different types of liquid with two different types of chemistries points towards two different episodes of liquid water interaction,” said Eva Scheller, also at Caltech.

It seems strange that the scientists were surprised that Jezero Crater has a history of volcanic activity. Most craters when formed have what is called impact melt in their crater interior. The impact not only carves out the crater, the heat of impact melts the rock. Possibly the scientists expected such impact melt to be well buried and not accessible to Perseverance.

Regardless, this data will be used as the baseline for documenting the geological history of this region on Mars as Perseverance continues its journey across the floor of the crater, up onto the delta, and then out of the crater into the uplands beyond.

Leave a comment

Cracking glaciers on Mars

11:47 am

Cracking glaciers on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was released today as the picture of the day for the high resolution camera on Mars Reconnaissance Orbiter (MRO). Located in the 2,000 long northern mid-latitude strip that I dub Mars’ glacier country, it shows many of the numerous glacial features that are routinely found in images taken in this region. According to Dan Berman, senior scientist at the Planetary Science Institute in Arizona, who wrote the caption,

This observation shows a lobe-shaped debris apron emanating from a massif (shown in the upper left of the image) in the Protonilus Mensae region in the Northern Hemisphere of Mars. These aprons are composed of nearly pure water ice with a layer of debris on the surface protecting the ice from sublimation (going directly from a solid to gaseous state). This image shows different terrain types on the apron that indicate the presence and flow of ice, from smoother polygonal terrain closer to the massif, to rougher, patterned ground commonly called “brain terrain.” Also visible on the apron are a series of linear pits.

Protonilus Mensae is the central mensae region in that mid-latitude strip of glaciers.The overview map below shows the location of this photo in that region. Also below is a close-up of the linear pits and cracked terrain surrounding that oblong mound, as indicated by the white rectangle.
» Read more

Leave a comment

Scientists discover underground reservoir of hydrogen, likely ice, near Martian equator

8:58 am

Detection of underground hydrogen in Valles Marineris
Click for full image.

In what could be a very significant discovery, scientists using Europe’s Trace Gas Orbiter (TGO) have discovered a surprisingly large underground reservoir of hydrogen, likely ice, near Martian equator and inside the solar system’s largest known canyon, Valles Marineris.

The map to the right, reduced to post here, provides all the important data. From its caption:

The coloured scale at the bottom of the frame shows the amount of ‘water-equivalent hydrogen’ (WEH) by weight (wt%). As reflected on these scales, the purple contours in the centre of this figure show the most water-rich region. In the area marked with a ‘C’, up to 40% of the near-surface material appears to be composed of water (by weight). The area marked ‘C’ is about the size of the Netherlands and overlaps with the deep valleys of Candor Chaos, part of the canyon system considered promising in our hunt for water on Mars.

What the caption does not note is the latitude of this hydrogen, about 3 to 10 degrees south latitude. Assuming the hydrogen represents underground ice, this would be the first detection on Mars below 30 degrees latitude, and the very first in the equatorial regions. Data from orbit has suggested that Mars has a lot of water ice, found near the surface more and more as you move into higher latitudes above 30 degrees and making Mars much like Antarctica. Almost no ice however had until now been detected below 30 degrees latitude. As the European Space Agency’s press release noted,
» Read more

6 comments

Visible clean water ice on Mars

11:57 am

Crater with ice scarp
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, is today’s picture of the day for the high resolution camera on Mars Reconnaissance Orbiter (MRO). Taken on September 13, 2021, it shows an exposed scarp on the southern inner wall of a small 800-foot-wide crater.

What makes that scarp intriguing is its blue color. As noted by Shane Byrne of the Lunar and Planetary Lab University of Arizona, who wrote the caption:

This north-facing cliff appears to expose icy material that’s similar to other pole-facing scarps showing buried ice elsewhere on the planet. These cliffs give us a cut-away view of the buried ice in that location and can help answer questions about what the Martian climate was like when this ice formed.

The crater itself sits inside a much larger crater, as shown in the wider picture below.
» Read more

7 comments

Curiosity looks back at its entire journey

10:03 am

Curiosity looking back across Gale Crater
Click for high resolution mosaic. Original images here, here, here, and here.

Wide overview map
Click for interactive map.

Cool image time! The mosaic above was created from four photos taken by Curiosity’s left navigation camera on December 12, 2021, just after the rover had moved into Maria Gordon Notch. The view is to the north, looking back at the rover’s journey climbing up the floor of Gale Crater into the foothills of Mount Sharp. The rim of Gale Crater can be seen about 25 to 30 miles away.

The cliff in shadow on the left is about 40 feet high. The cliff in sunlight on the right is between 30 to 60 feet high, depending on where you measure.

The overview map to the right shows Curiosity’s entire journey, with the yellow lines indicating the approximate area covered by the mosaic above. All told the rover has climbed about 1,700 feet since it landed. While much of the rover’s route is blocked from our view by the cliffs on left, the nearest sand dune sea in the center of the mosaic is the one that the rover circled around from January 2021 to June 2021.
» Read more

One comment

Curiosity takes a close look at a Martian cliff

11:15 am

A cliff of Mars
Click for full resolution. Original images here and here.

Curiosity has now moved up and into Maria Gordon Notch, a gap in the mountains of Gale Crater that is about forty feet wide, with a 40-foot-high cliff on its western side and a 30 to 60 foot cliff on its eastern side.

The mosaic above, created from two navigation camera images, looks up at the top half of that western cliff. Note the many many layers, each one of which records some climate or volcanic event in Mars’ geological history. The Mars we see today took a long time and many events to become what it is. Such layers however have not been seen everywhere by Curiosity. Compare for example this layered cliff with the massive outcrop dubbed Siccar Point and looked at closely by the rover in October. In that outcrop the layers were either non-existent, or merged together during some subsequent geological process.

Note also the pond of sand/dust at the center-bottom, nestled in a hollow but sitting almost vertical. That the dust can maintain itself at such an angle illustrates Mars’ lighter gravity, about 39% of Earth’s, which in turn allows for a much steeper angle of repose. That lighter gravity also allows for some sections of rock to stick out more precariously than possible on Earth.

As Curiosity moves through the notch in the next few days, more such cool pictures will become available, and I shall post them.

5 comments

Strange eroded glacial flows in unnamed crater on Mars

12:20 pm

Eroded glacial flows in unnamed crater on Mars
Click for full resolution image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on November 1, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a series of strange glacial-like flows coming off the western slopes of the central peak of a 40-mile-wide unnamed crater, located smack dab in what I call Mars’ glacier country, that 2,000 long mid-latitude strip where almost every image shows evidence of glaciers.

The cropped section to the right doesn’t really do these strange flows justice. Make sure you click on the image to see the full resolution version. There are numerous separate flows coming off that central peak. Each appears to show that as time passed, each flow traveled a shorter distance down the mountain, leaving a moraine behind at higher and higher points.

The overview map below provides the context.
» Read more

Leave a comment

Where Ingenuity and Perseverance presently sit in Jezero Crater

9:15 am

Perseverance and Ingenuity, December 8, 2021
Click for interactive map.

The map to the right, annotated to post here, shows the present location of the rover Perseverance (the red dot) in relation to the 17th flight of the helicopter Ingenuity (indicated by the green line and dot) that successfully occurred on December 5, 2021.

Perseverance has been very very very very slowly retreating south, following the same route it took to move into the rough sand dune region the scientists have dubbed Seitah. Based on their long term plans, the rover will retrace its path (the white dotted line) to its landing site, and then continue along the yellow dashed line to eventually reach the base of the delta, dubbed Three Forks, that in the distant past poured through a gap in the rim of Jezero Crater.

The helicopter meanwhile is also retracing its flights, heading north to the spot where Perseverance first placed it on the ground. Because of the seasonally thinner atmosphere, the helicopter’s flights during that return journey must be shorter, which is why the 17th flight only traveled halfway across Seitah. In crossing it the first time it had done so in one flight. Now it will take two.

During that 17th flight it appears that the topography between the rover and the helicopter’s landing site caused a loss of communications as the helicopter was landing.

The Ingenuity team believes the 13-foot (4-meter) height difference between the Perseverance rover and the top of Bras [an outcrop] contributed to the loss of communications when the helicopter descended toward the surface at the end of its flight.

That loss of communications apparently caused no problems, but it will likely mean that Ingenuity will do no more flights until Perseverance can get closer and better positioned.

Leave a comment

Curiosity moves into a mountain gap

10:51 am

Maria Gordon Notch
Click for full resolution version. Original images here and here.

Curiosity's location, December 6, 2021
Click for interactive map.

For the last three weeks the Curiosity science team has had the rover poking about at the base of the 40 foot cliff on the right of the panorama above. At that location many rocks and boulders had fallen from the top of the cliff, which gave them an opportunity to study the geology of the plateau above, even though it was literally beyond reach.

Beginning yesterday that work ended, and the science team finally made the commitment to move forward, into the gap above where the rover will turn right, climb up onto that plateau through a notch they have dubbed Maria Gordon Notch. The map to the right shows this coming route with the red dotted line.

Once in that notch Curiosity will truly be in the mountains of Gale Crater, even if those mountains are only the foothills to Mount Sharp.

It is interesting to contrast the roughness of the terrain that Curiosity is now routinely traveling, with the relatively benign ground that Perseverance is traversing on the floor of Jezero Crater. While Curiosity is pushing forward into steeper and rougher terrain, the Perseverance team is retreating from the somewhat mild sand dune ground of South Seitah, even though that ground is far less challenging than anything faced by Curiosity. You can see this retreat at the interactive map here. Zoom in and place your cursor over each waypoint. Rather than push forward, the Perseverance team seems willing to have the rover retreat and retrace its route around Seitah, even though to retrace those steps will likely take a few weeks, during which they will cover no new ground and will likely learn little new.

Why the Perseverance team seems so timid is puzzling. It could be they are still working out the kinks of their operation. It could be that they want to take no risks at all this early in their mission. And it could also be that the team culture at Perseverance is simply less daring than that of the Curiosity team.

Only time will answer this question. I suspect as the Perseverance mission unfolds its scientists will become more bold. We just need to give them time.

Leave a comment

Ingenuity’s images from 16th flight on November 21st

11:18 am

Ingenuity color image from 16th flight
Click for full image.

Cool image time! The photo to the right, reduced and enhanced to post here, was the first color image taken by Ingenuity during its 16th flight on Mars on November 21st. The picture was taken about fifteen seconds after take-off, and I think looks west toward the rim of Jezero Crater in the distance.

The flight itself was relatively short, essentially a quick hop about 380 feet to the north to land at the edge of the rough area dubbed Seitah. The team is going to slowly take the helicopter back to its initial landing field, Wright field, over several hops. This was the first.

If you want to peruse all 113 images from the flight, go here and set the sol range from 268 (November 20) to 274 (November 26). That will show all 113 images taken during the November 21st flight.

3 comments

Mars Express successfully relays data from Zhurong to Earth

10:21 am

The European Space Agency’s Mars Express orbiter has successfully been used to relay data from China’s Zhurong Mars rover to Earth and then to China.

In November, ESA’s Mars Express and CNSA’s Zhurong teams carried out a series of experimental communication tests in which Mars Express used this ‘in the blind’ mode to listen for signals sent to it by the Zhurong Rover.

The experiments culminated in a successful test on 20 November. “Mars Express successfully received the signals sent by the rover, and our colleagues in the Zhurong team confirmed that all the data arrived on Earth in very good quality.” says ESA’s Gerhard Billig.

Apparently, normal communications would first involve “handshake” communications between the two, but that requires communications frequencies Zhurong does not use. Mars Express instead had to grab the data on the blind. The test was a success, which means the ESA will likely act as another communications relay for Zhurong, in addition to China’s Tianwen-1 orbiter, as the rover’s mission on Mars continues.

Leave a comment

Sculptured lava south of Olympus Mons?

10:51 am

Sculptured lava?
Click for full image.

Time for a cool image! The photo to the right, rotated, cropped, and reduced to post here, was taken on September 8, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a region of strangely sculptured terrain located several hundred miles south of Olympus Mons.

It appears the prevailing winds are to the west. The question is whether the wind is shaping a hard lava surface, over eons, or is shaping instead layers of dust or volcanic ash quickly and seasonally. At this location either is possible. In fact, we might even be seeing evidence of both at the same time.

The overview map below shows that the location is just outside the Medusae Fossae Formation, the largest volcanic ash deposit on Mars.
» Read more

6 comments

Ingenuity completes 16th Mars flight

9:38 am

According to a tweet by the Ingenuity team, the Mars helicopter successfully completed its 16th flight on Mars on November 21st.

“#MarsHelicopter continues to thrive!” mission personnel wrote in a tweet posted Monday (Nov. 22). “The mighty rotorcraft completed its 16th flight on the Red Planet last weekend, traveling 116 meters northeast for 109 seconds. It captured color images during the short hop, but those will come down in a later downlink.”

No images have as yet been downloaded from the flight.

One comment

Video of Ingenuity’s 13th flight

11:47 am

Using the high resolution camera on Perseverance, the science team has now released two videos taken of Ingenuity’s 13th flight on Mars, on September 4, 2021.

One is a very wide view, which makes it hard to see the helicopter. The closer view can be seen here.

At the beginning of the video, Ingenuity is near the lower left of frame, at a distance of about 980 feet (300 meters) from the rover. It climbs to an altitude of to 26 feet (8 meters) before beginning its sideways translation. The helicopter leaves the camera’s field of view on the right. Soon after, the helicopter returns into the field of view (the majority of frames that did not capture helicopter after it exited the camera’s field of view were purposely not downlinked from Mars by the team) and lands at a location near its takeoff point.

One comment

Volcanic vent on Mars

2:43 pm

Overview of Arsia Mons pits

To understand today’s cool image we really should start from a distance and zoom in. The overview map to the right focuses in on the two southernmost giant volcanoes in the string of three that sit to the east of Mars’ biggest volcano, Olympus Mons, and to the west of the planet’s biggest canyon, Valles Marineris.

The black dots mark the locations of the many high resolution photos taken by Mars Reconnaissance Orbiter that I have featured previously on Behind the Black. Many are isolated openings with no related geological features. Others appear to be skylights into a more extensive lava tube, hinted at by either a continuing surface depression or a series of similar skylights.

The white dot marks the location of today’s cool image, about 350 miles south of Arsia Mons’ caldera.
» Read more

2 comments

UAE Al-Amal Mars orbiter finds surprising variations in Mars atmosphere

10:32 am

Oxygen variations in Martian atmosphere
Click for full graphic.

The United Arab Emirates Al-Amal (“hope” in English) Mars orbiter has discovered unexpected variations of oxygen and carbon monoxide in the Martian atmosphere.

The EMM team had expected to observe a relatively uniform emission from oxygen at 130.4 nm across the planet and yet here we are, faced with unpredicted variations of 50% or more in the brightness.

The image to the right, cropped and reduced to post here, shows the variations in oxygen on Mars’s dayside. Though the map does not indicate the geography below, the concentration of oxygen in the northern latitudes appears to correspond to the planet’s northern lowland plains. In fact, the variations should not have been a surprise, since the surface of Mars has such a stark dichotomy between its northern and southern hemispheres.

Leave a comment

Ingenuity’s 16th Martian flight is now scheduled for November 18

9:27 am

According to an update today from the Ingenuity science team, Ingenuity’s sixteenth flight on Mars is scheduled for no earlier than November 18th, and will be a relatively short hop of about 100+ meters to the north, compared to previous flights.

It appears the roughness of the terrain on this flight can cause an accumulating error in its flight software. Because the landing area is also rough, they want to bring the helicopter down sooner to make sure it lands close to where it should.

The present plan is to hop north to return to the location of Ingenuity’s first flight, at Wright Brothers Field. Along the way they will also consider installing an update in the flight software to improve the helicopter’s capabilities.

Leave a comment

Craters in the soft Martian northern lowland plains

12:25 pm

Craters in the soft Martian northern lowland plains
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was a featured image today from the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The caption, written by Carol Weitz of the Planetary Science Institute in Arizona, focused on the wind patterns created within these craters.

These impact craters in the northern middle latitudes have interesting interiors: all of them have wind-blown (aeolian) ripples.

Outside of the craters and along the crater floors, the ripples are all oriented in the same direction. However, along the walls of some of the larger craters, the ripples are situated radially away from the center, indicating the winds moving inside the larger craters can be influenced by the topography of the crater wall.

Additionally, many of the larger craters have layered mesas along their floors that are likely sedimentary deposits laid down after the craters formed but prior to the development of the aeolian ripples.

I am further intrigued by the rimless nature of these craters, as well as the lack of significant rocky debris at their edges. They all look like the bolides that created them impacted into a relatively soft surface that, rather than break up into rocks and boulders, melted, flowed, and then quickly refroze into these depressions.

The location, as always, provides us a possible explanation.
» Read more

2 comments

Zhurong’s continuing travels on Mars

10:26 am

Zhurong overview map
Click for original map.

This past week the Chinese press released a new but limited update on the status of both its Mars orbiter Tianwen-1 and its Mars rover Zhurong.

The map to the right uses as its background a high resolution picture from Mars Reconnaissance Orbiter. I have superimposed Zhurong’s route in green. You can get an idea of how far the rover has traveled since resuming communications with Earth in late October by comparing this map with the one I posted then. After stopping at a small sand dune (the crescent-shaped white features), it curved around to head to the southeast towards a rough area and a trough that is thought to be filled with sediment.

Meanwhile, the orbiter has shifted its orbit, changing from one dedicated mainly as providing a communications relay between Zhurong and Earth to one that now allows it to begin a two-year photographic survey of Mars.

To supplement the resulting gaps in communications for Zhurong, China and the European Space Agency (ESA) have made their first test using ESA’s Mars Express satellite as a relay satellite. Both hope to know soon whether it worked.

In either case, Zhurong’s travels will likely be slowed somewhat due to the reduction in communications access.

Leave a comment

Snow on Martian dunes

12:58 pm

Snowy dunes near the Martian north pole
Click for full image.

Close-up of snowy dunes
Click for full image.

Cool image time! The first photo to the right, rotated, cropped, and reduced to post here, was taken on September 19, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what appears to be snow nestled in the hollows of many dunes.

The second photo, cropped to post here, shows in high resolution the area in the white box.

Is that snow water, or dry ice? The location is very far north, 76 degrees latitude, so it could be either. Since the photo was requested by Candice Hansen of the Planetary Science Institute in Arizona, I emailed her to ask. Her answer:

Early in the spring all the bright stuff is dry ice. As it gets later in the spring it is probably still mostly dry ice but with HiRISE images alone we cannot really distinguish the composition of the ice. In-between the dunes it is almost certainly bare ground late in the spring, but since the dunes are dark the surface just looks bright in contrast

This picture was taken in summer, which suggests the snow is probably water, not dry ice. Yet, all the snow is found in the north-facing hollows, places that will remain mostly in shadow at this high latitude, 76 degrees north. Thus, it is possible that the snow is the last remaining traces of the thin dry ice mantle that covers the Martian poles down to about 60 degrees latitude during the winter, and sublimates away in summer.

Hansen had requested a whole bunch of similar images of such snowy dunes. As she explained,
» Read more

2 comments

A volcanic extrusion on the floor of Valles Marineris?

2:52 pm

A volcanic extrusion on the floor of Valles Marineris?
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on August 31, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels a “possible contact between two units.”

I think that contact is the point where that eroded mountain touches the surrounding smooth canyon floor. The mountain itself looks to me to be a very eroded extrusion of lava that was placed there from below a very very long time ago, covered later by material, and now exposed for a long enough period that its surface appears to have been carved by wind and even possibly flowing water or ice.

Because it is lava it is more resistant to erosion, which is why it sits higher than the smooth terrain around it. Even though both experienced the same processes of wear over time, the mountain’s surface was only carved away partly, while the material that had been in the floor was washed away entirely.

This is all a guess. However, a look below at the overview map, showing this mountain’s location on Mars, as well as MRO’s wider view from its context camera, I think strengthens my hypothesis.
» Read more

Leave a comment

Frozen lake bed in the Martian high latitudes?

2:03 pm

Frozen lakebed in the Martian high latitudes?
Click for full image.

Today’s cool image comes from today’s Mars Reconnaissance Orbiter’s (MRO) high resolution picture of the day, rotated and cropped to post here. The original was taken back on March 28, 2017.

What formed those strange circular ridges and the many small cracks and hollows? The caption provided is somewhat vague and I think confusing:

This formation looks like a crater from a meteor impact rather than an ancient caldera of a volcano. Connected to the crater is a carved-out area that resembles a lake bed. At high resolution, we might be able to determine the likelihood of a water lake bed or lava bed. This observation will give insight into some of the interesting geology of this area.

The crater this caption is referring to is not visible in the image provided. It can be seen to the west of this location, in the MRO context camera picture below.
» Read more

Leave a comment

Curiosity: Approaching the saddle

9:21 am

The saddle ahead
Click for full image.

Cool image time! The photo to the right, reduced to post here, was taken on November 5, 2021 by Curiosity’s high resolution camera, and looks forward at its planned route up onto the saddle ahead, where the rover will turn right and climb up into Maria Gordon Notch. (See this October post for a map outlining the rover’s future travels.) I think that cliff face is between 40 to 60 feet high, though this is a very wild guess.

As noted by Abigail Fraeman of JPL on the Curiosity blog on November 3, 2021,

The terrain is beginning to steepen as Curiosity gets close to the end of this region, so even though we’re only a few drives away from our last drill site … we’ve already climbed 25 m higher!

The route ahead looks equally steep, though the ground actually appears less rough, with fewer large jagged boulders that Curiosity must avoid to protect its wheels.

It will likely be at least one to three weeks however before Curiosity gets to that saddle. The science team has begun a drilling campaign at the present location, and this will take time, depending on how many holes they decide to drill.

One comment
1 … 25 26 27 28 29 … 78