Tag: engineering

Scientists discover that mid-sized dunes near Mars’ north pole move

11:41 am

Mars' North Pole

Scientists using images from Mars Reconnaissance Orbiter (MRO) collected over six Martian years (6.5 Earth years) have found that the mid-sized dunes dubbed mega-dunes near the north pole actually do move from year to year, unlike similar sized dunes elsewhere on the planet.

Megaripples on Mars are about 1 to 2 meters tall and have 5 to 40 meter spacing, where there size falls between ripples that are about 40 centimeters tall with 1 to 5 meter spacing and dunes that can reach hundreds of meters in height with spacing of 100 to 300 meters. Whereas the megaripples migration rates are slow in comparison (average of 0.13 meters per Earth year), some of the nearby ripples were found to migrate an average equivalent of 9.6 meters (32 feet) per year over just 22 days in northern summer – unprecedented rates for Mars. These high rates of sand movement help explain the megaripple activity.

Previously it was believed that such dunes were static planetwide, left over from a time when Mars’ atmosphere was thicker and could then move them more easily. This data however suggests that the winds produced over the north pole when the carbon dioxide in the atmosphere freezes in winter and sublimates back to a gas in summer are sufficient to shift these dunes in the surrounding giant Olympia Undae dune sea.

0 comments

Orbit Fab wins contract to refuel Astroscale’s satellite repair robots

10:26 am

Capitalism in space: Orbit Fab today announced that it has won a contract to provide up to 1,000 kilograms of xenon fuel for the satellite robots launched by the private company Astroscale and designed to repair other satellites.

Orbit Fab, a startup founded in 2018, developed a refueling port known as RAFTI, short for Rapidly Attachable Fluid Transfer Interface. The port is being offered to government and commercial operators to make their satellites compatible with Orbit Fab’s refueling tankers.

The company last year deployed its first propellant-storage tanker in low Earth orbit and plans to launch its first tanker to geostationary orbit on a SpaceX Falcon 9 lunar lander mission projected for late 2022 or early 2023. Orbit Fab’s first two fuel shuttles in LEO are expected to be operational in 2023.

Once Astroscale begins launching its repair robots in ’26, those robots will be able to extend their life by refilling their tanks from Orbit Fab’s tankers, and thus repair more satellites while in orbit, thus serving more customers.

0 comments

InSight recovering from safe mode caused by Martian dust storm

9:34 am

Engineers have been able to regain contact with the Mars lander InSight after a Martian dust storm that put it in safe mode and cut off all communications for three days.

The mission’s team reestablished contact with InSight Jan. 10, finding that its power was holding steady and, while low, was unlikely to be draining the lander’s batteries. Drained batteries are believed to have caused the end of NASA’s Opportunity rover during an epic series of dust storms that blanketed the Red Planet in 2018.

The lander remains however in safe mode. The engineers hope they can resume limited science operations in about a week. Even before this even the limitations on InSight’s power generation due to dust on its solar panels had forced the science team to only gather data from the seismometer, and even then had to suspend all data gathering periodically.

Though the lander has survived this dust storm, it is presently unclear how much dust remains on its panels and thus how much power it can generate. If it only can generate enough power to keep the lander from freezing, but not do any science, it might be time to shut it down entirely.

0 comments

A butte on Mars

11:13 am

A butte on Mars
Click for full photograph.

Cool image time! Because the Martian geology inside the enclosed stone valley beyond Maria Gordon notch is so complex and exposed, the Curiosity science team is spending a lot of time there. As noted in their January 7th update:

[W]e are marvelling at the landscape in front of us, which is very diverse, both in the rover workspace and in the walls around us. It’s a feast for our stratigraphers (those who research the succession in which rocks were deposited and deduce the geologic history of the area from this). We are all looking forward to the story they will piece together when they’ve had a bit of time to think!

The image to the right, cropped and reduced to post here, was taken by the rover’s high resolution camera on December 18th, soon after it entered this stone valley and was part of scan covering both this butte as well as a nearby cliff. I had previously featured a close-up of the top of this butte and its incredible overhang on December 20, 2021. This image however shows the whole butte, which I estimate to be about 30 to 40 feet high is about 10 feet high.

Not only does the butte illustrate well the alien nature of this stark and barren Martian terrain, so does all the terrain surrounding it. The surface everywhere is nothing but pavement stones of all sizes. Once again, there is no life, something you practically never see on Earth.

6 comments

A tumbling 1,100-foot-wide asteroid

10:04 am

Nereus tumbling on December 10th close approach
Click for full image.

Using the Goldstone radio antenna in California, scientists have been able to take some of the highest resolution radar images of the 1,100-foot-wide asteroid Nereus during its close approach to Earth on December 10, 2021.

The montage to the right, cropped to post here, shows twelve images from the 39-image sequence, which can also be viewed as an animation here.

During the asteroid’s close approach, an image resolution of about 12.3 feet (3.75 meters) per pixel was possible, revealing surface features such as potential boulders and craters, plus ridges and other topography. Asteroid Nereus’ previous approach in 2002 was near enough to Earth to reveal the asteroid’s size and overall shape, but too distant to show surface features. The new observations will also help scientists better understand the asteroid’s shape and rotation while providing them new data to further refine its orbital path around the Sun.

The asteroid will not make a similar close-approach again until 2060.

5 comments

SpaceX pushing to launch 2nd generation Starlink satellites by March

9:36 am

Capitalism in space: In paperwork filed by SpaceX to the FCC, it has announced it is pushing to launch the first second generation Starlink satellites by March, 2022.

While some news reports have suggested that SpaceX intended to launch those upgraded satellites on Starship, this reporting is certainly wrong. As the article at the link correctly notes, SpaceX does not have to state what rocket it plans to use in its paperwork. It could very easily launch these first upgraded satellites on a Falcon 9.

The story however does provide this interesting tidbit about the FCC’s treatment of SpaceX in this licensing process:

SpaceX filed the first unmodified Gen2 Starlink application with the FCC in May 2020, requesting permission to launch an unprecedented 30,000 satellites. While the size of the proposed constellation is extraordinary, the FCC has also been exceptionally slow to process it. Only five months after SpaceX submitted its Starlink Gen2 modification request and nineteen months after its original Gen2 application did the FCC finally accept it for filing, which means that it has taken more than a year and a half to merely start the official review process. [emphasis in original]

In other words, the FCC stalled SpaceX for more than a year and a half. If the DC bureaucracy can play such games with Starlink, this suggests it might very well be doing the same with the approval of the environmental reassessment for SpaceX’s Boca Chica facility, which the FAA has now delayed repeatedly since last year. There are many people in Washington, both in the Biden administration and in the established and permanent bureaucracy, who do not like SpaceX’s success or its independence, and wish to use government power to squelch it. This story provides us some evidence that such misuse of government power in the FAA is very likely occurring.

3 comments

An independent Russian private space company?

9:20 am

Capitalism in space? The Russian company S7 Space announced today that plans to soon begin tests of the fuel tanks of its proposed reusable smallsat rocket, and is in the process of deciding what Russian facility to use.

“We plan to test the rocket’s elements, namely fuel tanks of a smaller size, with a diameter of 1.5 meters. The trials are aimed at proving that the structure is durable. A concrete laboratory is yet to be selected for the purpose. In other words, there has been no firm contract for trials so far,” [explained the head of the company’s technological research department, Arseny Kisarev.]

The official expressed hope that the trials would be carried out by TsNIIMash (Central Research Institute of Machine Building), a main research institution of Russia’s state-run space corporation Roscosmos.

“However, choosing another lab is also possible, if it corresponds to our requirements of the testing procedure,” he said.

This rocket was first announced in 2019. Development was suspended in 2020, however, when the Putin government imposed new much higher fees on the company for storing the ocean launch platform Sea Launch, fees so high that the company was soon negotiating to sell the platform to a Russian state-run corporation.

It is not clear whether that sale ever occurred, but the company itself appears only now to be resuming some operations. Though today’s story suggests it is operating independent of the control of Roscosmos and the Russian government, this is quite doubtful. Russia today functions much like the various Mafia mobs in the U.S. The various different government agencies divide up the work into “territories” that belong to each company. No other independent company can enter that territory and compete for business. Since S7 Space wants to build its own rocket, that makes it a direct competitor with Roscosmos and the government design bureaus within it that build the various Russian rockets.

More likely Roscosmos wants S7 Space to survive, but under its control and only for the purpose of building a smallsat rocket for Roscosmos. S7 Space appears to be struggling to stay independent, with this announcement likely part of that struggle.

2 comments

Strange land forms on the flanks of Mars’ Arsia Mons volcano

1:24 pm

Strange landforms on the flanks of Arsia Mons
Click for original image. Click here for the context camera image.

Cool image time! The center of the photo to the right was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on September 5, 2021. For posting here I have rotated, cropped, and reduced it, as well as added to each side the lower resolution context camera image of this region.

The ground slopes downhill to the north. Make sure you click on the image to see the full resolution version. In only a few miles the terrain changes from a mound with small knobs to a smooth area with few knobs to a chaotic area where the larger ridges and knobs are the dominant feature, with hollows and canyons in between.

You should also take a look at the full context camera image. Just to the southeast of the above picture is a large depression that looks like it has been filled with lava, with its western rim covered by that flow. Scientists have taken a lot of high resolution pictures of this depression with MRO, trying to decipher its geology.
» Read more

4 comments

Data from China’s Chang’e-5 lander detects very tiny amounts of water in lunar soil

9:29 am

The uncertainty of science: In a paper published yesterday, Chinese scientists revealed that data from an instrument on the Chang’e-5 lunar lander has detected evidence of very tiny amounts of water in lunar soil, amounts that confirm past data showing the Moon is very dry.

From China’s state-run press:

The study published on Saturday in the peer-reviewed journal Science Advances revealed that the lunar soil at the landing site contains less than 120 ppm water or 120g water per ton, and a light, vesicular rock carries 180 ppm, which are much drier than that on Earth. … The additional 60 ppm water in the rock may originate from the lunar interior, according to the researchers. [emphasis mine]

It is believed that most of this water is the result of hydrogen in the solar wind.

The paper can be found here.

Before we begin dancing in joy that the Moon is wet, reread the highlighted words. This data instead simply confirms past data that the Moon is very dry. In the paper itself, it is made very clear that this high water content, small as it is, was only detected in a single rock, with all of the surrounding terrain much much drier. From the paper:

The water contents are less than 30 ppm in most measured regolith spots except for [areas] D12 and D17, which may be due to the disturbance of the top layer of the more space-weathered/solar wind–implanted regolith by the lander exhaust and the subsequent sampling process. The unsampled areas of D12 and D17 may have been shielded by [a rock] from the lander exhaust and thus retain the top space-weathered layer that contains higher water content. We predict that higher water content may be found in surface regolith than that from the subsurface of the returned borehole samples if the original stratigraphy is preserved. The estimated water contents of the regolith in the landing area are in agreement with those measured in the Apollo regolith samples and the orbital observations.

In other words, the higher water content, still very dry, appears to only exist on the surface, which is why they suspect it is produced by the solar wind and is also very temporary.

Moreover, there are many uncertainties in this result. The detection might not even be water, but hydroxyl molecules.

What this study suggests is that the patches of suspected water that some orbiters think they have identified in low latitudes on the Moon may simply be these surface molecules left by the solar wind, and that if there is usable water on the Moon, it will only be found in those permanently shadowed craters at the poles, if there.

7 comments

Webb’s primary mirror successfully deployed

2:54 pm

Today engineers successfully completed the unfolding of the primary mirror on the James Webb Space Telescope.

The two wings of Webb’s primary mirror had been folded to fit inside the nose cone of an Arianespace Ariane 5 rocket prior to launch. After more than a week of other critical spacecraft deployments, the Webb team began remotely unfolding the hexagonal segments of the primary mirror, the largest ever launched into space. This was a multi-day process, with the first side deployed Jan. 7 and the second Jan. 8.

Mission Operations Center ground control at the Space Telescope Science Institute in Baltimore began deploying the second side panel of the mirror at 8:53 a.m. EST. Once it extended and latched into position at 1:17 p.m. EST, the team declared all major deployments successfully completed.

Next step over the next few months will be aligning the primary mirrors 18 segments with each other as well as the secondary mirror. First science images are expected during the summer, but do not be surprised if NASA releases some test images before then, should all be well and it obtains some eye candy.

9 comments

Debris in Perseverance core sample equipment

9:07 am

Debris in core sample carousel on Perseverance
Click for full image.

In attempting to store its sixth core sample on Mars last week, engineers discovered that Perseverance could not do so because several small pieces of the core sample had fallen into the equipment and prevented the drilling bit with the core from inserting itself completely into the sample storage carousel.

To understand the issue precisely, the engineers commanded Perseverance to first extract the bit from the carousel so they could get pictures of it.

The extraction took place yesterday (1/6) and data was downlinked early this morning. These most recent downlinked images confirm that inside the bit carousel there are a few pieces of pebble-sized debris. The team is confident that these are fragments of the cored rock that fell out of the sample tube at the time of Coring Bit Dropoff, and that they prevented the bit from seating completely in the bit carousel.

The photo to the right shows that material at the image’s bottom.

It appears this issue was anticipated when the rover was designed giving engineers a way to remove the debris. They plan to do so, but will proceed slowly as this will be the first time it will be attempted on Mars.

1 comment
1 … 486 487 488 489 490 … 1,352