Erik Wernquist – One revolution per minute
An evening pause: A short film that attempts to visualize what it would really be like to be on a rotating interplanetary spaceship, with artificial gravity. Quite mesmerizing.
Hat tip Rex Ridenoure.
Tag: engineering
Striped terrain on Mars
Click for original image.
Today’s cool image will be a mystery with the answer below the fold. Before you look at the answer, however, you must try to come up with your own explanation for the picture to the right, cropped to post here, that was taken on September 25, 2018 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
What we see in this picture is what looks like a striped terrain, alternating bands of light and dark. What caused the bands? Why the different colors?
The overview map above provides some clues. The white rectangle inside Juventae Chasma near the map’s center marks the area within which this picture was taken, though the picture to the right covers only about a pixel inside that rectangle.
Can you guess what these stripes reveal, from this little information? For this quiz to work you must make a guess, but be prepared to be wrong and quickly reassess your conclusions. Such is the real scientific method, so rarely taught now in schools.
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Ariane-6’s core stage completes full 7 minute engine test
Engineers yesterday successfully completed a two-hour dress rehearsal countdown and fueling of an Ariane-6 first stage followed by a full seven minute engine burn, simulating what that stage would do during a launch.
The test took place on Ariane-6’s launchpad in French Guiana.
The November 23 test sequence was run the same way as the previous ones, with a launch sequence and final countdown representative of a launch, including removal of the mobile gantry and filling the launcher’s upper and core stage tanks with liquid hydrogen (-253° Celsius) and liquid oxygen (-183° Celsius). The test ended with the ignition of the core stage Vulcain 2.1 engine, followed by more than 7 minutes of stabilized operation covering the entire core stage flight phase. All functional aspects of Ariane 6’s core stage during the flight phase were tested.
According to the European Space Agency, only one more engine test of the Ariane-6’s upper stage remains before the spring launch can be attempted, and that engine test is planned for next month in Germany.
With the retirement of the Ariane-5 rocket in July, Europe has had no large rocket to launch payloads. Originally Ariane-6’s first launches were supposed to be in parallel with Ariane-5’s last launches, but its development is four years behind schedule.
China delays till ’25 the launch of its Hubble-class optical space telescope
China today revealed that it is delaying the the launch of its Xuntian space telescope from early next year to 2025.
Zhan Hu, project scientist of Xuntian space telescope system, revealed that the delay was necessary for the team to finalize a preflight “engineering qualification model.” This model will undergo rigorous performance tests early next year. Despite the setback, China is making significant strides by domestically developing all five instruments for Xuntian, a first for the country, Scientific American reported.
The optical telescope, designed to somewhat comparable to Hubble, is intended to fly close to China’s Tiangong-3 space station where astronauts will periodically fly over to do maintenance and repair. Its primary mirror, two meters in diameter, is only slightly smaller than Hubble’s 2.4 meter mirror.
The article says the launch was supposed to happen before the end of this year, but that is incorrect. The launch has been targeting the spring of 2024 since February.
China launches classified satellite
China today used its Long March 2D rocket to launch what it described as “a technology experiment satellite for satellite internet technologies”, the rocket lifting off from its Xichang spaceport in the southwest of China.
No other information was released. While the satellite could be a test satellite for a constellation comparable to Starlink, the lack of information suggests otherwise.
No word also on whether the rocket’s first stage, using toxic hypergolic fuels, landed near habitable areas. The drop zone was over heavily populated areas in China.
Furthermore, China’s Kuaizhou-1 rocket had also been expected to launch today from Xichang in the wee hours of the morning, also carrying a classified payload. No word yet on whether that launch occurred, was scrubbed, or was simply the Long March 2D launch, the name of the rocket misunderstood prior to launch because of China’s secrecy.
Putting that unknown launch aside, here are the present leaders in the 2023 launch race:
86 SpaceX
53 China
14 Russia
7 Rocket Lab
7 India
American private enterprise still leads China 98 to 53 in successful launches, and the entire world combined 98 to 83. SpaceX by itself still leads the rest of the world (excluding American companies) 86 to 83.
Martian ice sheets sublimating like peeling paint?
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 19, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The features are described as “ribbed terrain” in the label. To my eye they more resemble flakes of peeling paint, most especially the mesas in the lower left. On the full image there are many more examples that resemble old paint peels, barely attached to the wall.
The white dot on the overview map above marks the location, deep inside the 2,000-mile-long strip in the northern mid-latitudes I dub glacier country, because everything seems covered by glacial features. This location is at 42 degrees north latitude, where plenty of near-surface ice features are found on Mars.
At first glance it looks like the top “paint-peel” layers to the south have been slowly sublimating away, leaving behind the smooth plain to the north. The problem is that this smooth area in the full image actually appears to be a glacial ice sheet of its own, filling all the low areas between mesas.
In other words, we are probably looking at layers and layers of ice sheets, each created during a different Martian climate cycle, caused by the wide swings of the planet’s rotational tilt, or obliquity.
The location is within Arabia Terra, the largest transitional zone on Mars between the northern lowland plains and the southern cratered highlands. Thus it sits above the glaciers that fill the lower regions of chaos to the north. What we have here is terrain that will eventually become chaos terrain, as the narrow faults and cracks are slowly widened into canyons by the cycles of glacial activity.
Eutelsat-OneWeb gets license approval in India
Less than two weeks after SpaceX obtained regulatory approval to offer its Starlink system in India, Eutelsat-OneWeb (newly merged) has now gotten its own approval.
Eutelsat-OneWeb is half owned by an Indian investment firm, so it is no surprise it obtained this approval soon after SpaceX. The two companies will now be competing aggressively for business in this giant country, whose technological capabilities has been renewed in recent years by the abandonment of a socialist/communist government for a leadership focused on encouraging freedom, capitalism, and competition.
NASA laser communication experiment succeeds in sending data from beyond Moon
A NASA laser communication experiment on the asteroid probe Psyche succeeded on November 14, 2023 in sending data to and from the spacecraft as it traveled away from Earth.
NASA’s Deep Space Optical Communications (DSOC) experiment has beamed a near-infrared laser encoded with test data fromnearly 10 million miles (16 million kilometers) away – about 40 times farther than the Moon is from Earth – to the Hale Telescope at Caltech’s Palomar Observatory in San Diego County, California. This is the farthest-ever demonstration of optical communications.
Riding aboard the recently launched Psyche spacecraft, DSOC is configured to send high-bandwidth test data to Earth during its two-year technology demonstration as Psyche travels to the main asteroid belt between Mars and Jupiter. NASA’s Jet Propulsion Laboratory in Southern California manages both DSOC and Psyche.
The experiment seeks to demonstrate the advantages of optical communications, which if successful could have data speeds ten to a hundred times faster than standard high band radio communications. While the technology has been demonstrated as far away as the Moon, this is the first successful test from deep space, a key advance that suggests the technology is becoming mature enough to use on planetary missions.
If so, it could largely replace or at least supplement the various radio-antenna networks on Earth, such as NASA’s Deep Space Network, with smaller and more efficient communication links.
North Korea launches spy satellite
In its third attempt this year to launch a spy satellite, North Korea today succeeded at last, its new Chollima-1 rocket lifting off from Sohae spaceport on the country’s western coast and placing in orbit what is probably a relatively primitive spy satellite with a limited lifespan.
Though launched on the coast, the flight path crossed over North Korea, with drop zones for the rocket’s lower stages in the Yellow and East China seas. The previous two launch failures (in May and August) did the same, with South Korea salvaging stages and the satellite from the first failure. The data recovered suggested the spy satellite was of “no military utility” according to the South Korean military.
As usual, U.S. and South Korean officials condemned the launch, calling it a violation of UN sanctions. Note too that this was not North Korea’s first successful launch, having managed launches in 2012 and 2016 previously, with a different rocket.
Because this was North Korea’s first success in 2023, the leader broad in the 2023 launch race remains unchanged:
86 SpaceX
52 China
14 Russia
7 Rocket Lab
7 India
However, the launch was the 180th in 2023, setting a new global record for the launches in a single year, eclipsing the record set last year. Since Sputnik in 1957 the average number of successful launches globally was generally less than a hundred. This year it is very possible the world will double that average, almost entirely because of American private enterprise, which leads China 98 to 52 in successful launches, and the entire world combined 98 to 82. SpaceX by itself still leads the rest of the world (excluding American companies) 86 to 82.
SpaceX launches 23 more Starlink satellites
SpaceX early last night continued its campaign to reach 100 launches in 2023, its Falcon 9 rocket launching for the third time in just over four days, lifting off from Cape Canaveral carrying 23 more Starlink satellites into orbit.
The first stage completed its fifteenth launch, landing on a drone ship in the Atlantic.
The leaders in the 2023 launch race:
86 SpaceX
52 China
14 Russia
7 Rocket Lab
7 India
American private enterprise now leads China 98 to 52 in successful launches, and the entire world combined 98 to 81. SpaceX by itself is now leads the rest of the world (excluding American companies) 86 to 81.
With this launch, the number of successful orbital launches in 2023 now matches the record total of 179 set last year. With a little more than five weeks to go, expect that number to top 200 before the year is out, especially because China has historically tended to launch a lot of rockets in December.
Ancient volcanic vent on Mars
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).
The picture label describes it as a “Low Shield Vent and Pit Northeast of Arsia Mons,” suggesting these depressions are volcanic in nature. We know the pit in the lower left is not an impact crater because it has no raised rim of ejecta. Instead, it looks like a collapsed sinkhole, formed when the ceiling above a void could no longer support its weight. Similar, the trench to the northeast is aligned with the downhill grade to the northeast, with its features suggesting a vent draining in that direction.
The ample dust inside the trench and pit suggest that it has been a very long time since this vent was active. Research suggests volcanic activity last occurred in this region from 10 to 300 million years ago, so that gives us a rough estimate of this vent’s age. Since then any dust that is blown into it will tend to become trapped there.
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North Korea announces it will attempt orbital launch of spy satellite this week
North Korea has announced that it will make a third attempt to place a spy satellite into orbit this week, lifting off anytime between November 22nd and December 1st, with drop zones of the rocket’s lower stages over the Yellow and East China seas.
The North initially planed to make the third launch attempt in October following two botched launches — in August and May. But it did not press ahead with the plan last month, raising speculation that it might need more preparation time.
As expected, South Korea has protested. It is also likely gearing up to attempt to recover as much debris from the launch as possible, as it did successfully on the previous launches.