Tag: spaceflight

Big scallops in the Martian southern latitudes

12:11 pm

Big scallops on Mars
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, shows an example of some large scalloped depressions in the high southern latitudes of Mars.

Taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on June 27, 2020, these scallops resemble in many ways the ice scarps that scientists have previously found at this same latitude, both to the east and west of where these scallops are located. With those scarps, the data suggests that a very pure layer of ice is visible in the cliff face, and that over time the cliff retreats northward due to sublimation of that ice.

The scallops in the photo to the right suggest the same process, though the differences raise questions. As explained by Colin Dundas of the U.S. Geological Survey’s Astrogeology Science Center in Arizona,
» Read more

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The liquids in Titan’s lakes stratify into different density layers

9:50 am

Using the data archive from the Cassini mission to Saturn, scientists now think that the liquids in Titan’s lakes can stratify into different density layers.

Lakes on Saturn’s moon Titan, composed of methane, ethane, and nitrogen rather than water, experience density driven stratification, forming layers similar to lakes on Earth. However, whereas lakes on Earth stratify in response to temperature, Titan’s lakes stratify solely due to the strange chemical interactions between its surface liquids and atmosphere, says a paper by Planetary Science Institute Research Scientist Jordan Steckloff.

Stratification occurs when different parts of a lake have different densities, with the less dense layer floating atop the denser layer. On Earth, lakes in temperate climates often stratify into layers in the summer as the Sun heats the surface of the lake, causing this water to expand and become less dense, forming a layer of warm water that literally floats upon the cooler water below. This density-driven stratification can occur on Titan as well; however it happens due to the amount of atmospheric nitrogen that Titan’s surface liquids can dissolve, rather than the liquids warming up and expanding.

…Because liquid methane is less dense than liquid ethane, it has been long assumed that Titan’s methane would generally float atop its liquid ethane. However, when methane’s affinity for atmospheric nitrogen is accounted for, methane can dissolve sufficient nitrogen at low temperatures to become denser than ethane.

This result has a great deal of uncertainty, mostly because of the relatively small dataset available of Titan. What it really shows is the possibility of this phenomenon. To confirm it will require some in situ measurements.

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NASA & SpaceX set Oct 31st for next manned Dragon mission

9:22 am

Capitalism in space: NASA and SpaceX have now scheduled Oct 31st as the target launch date for the first operational manned Dragon mission to ISS, the second manned Dragon mission overall.

This new date delays the launch a week from the previous announced schedule, and was done to give some space between its launch and the launch of a manned Soyuz on October 14th and the return of a different Soyuz with the present ISS crew on October 21st.

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UAE leader confirms goal to land rover on Moon by ’24

9:15 am

The new colonial movement: The ruler of the United Arab Emirates (UAE) has confirmed the initiation of a project to land a rover on the Moon by 2024, and have it built entirely by UAE engineers.

The Emirates Lunar Mission will be a 100 percent Emirati-built lunar rover that will land on the moon by 2024, according to a series of tweets by Sheikh Mohammed bin Rashid Al Maktoum, the UAE Prime Minister and Vice President and Ruler of Dubai.

The lunar rover has been named “Rashid” in honour of Sheikh Rashid bin Saeed Al Maktoum who ruled Dubai for 32 years from 1958 until his death in 1990 and who “sparked” the emirate’s advancement.

This is an ambitious goal, but not completely unreasonable. Their engineers were closely involved in the construction of their Hope Mars orbiter, mostly built by U.S. universities and subcontractors. That knowledge can now be applied to their own spacecraft. I also suspect that their 2016 agreement with India to invest billions there in exchange for space-related engineering assistance included technical information about India’s own lunar rover missions.

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ISS air leak still unlocated

9:04 am

The small air leak that was found on ISS a year ago has still not been located, despite a second weekend where the crew isolated themselves in one module and closed the hatches on all other modules so that ground engineers could track any air supply changes.

At a Sept. 28 briefing about the upcoming Northrop Grumman NG-14 Cygnus cargo mission to the station, a NASA official said that the weekend isolation in the Zvezda module failed to immediately locate the source of the leak. “As of this morning, there was no clear indication of where the leak is,” said Greg Dorth, manager of the ISS Program External Integration Office at NASA. “The teams are still looking at the data and evaluating it.”

This was the second time the ISS crew confined themselves to Zvezda in an effort to track down the leak. A month earlier, the three also spent a weekend in Zvezda with the other modules sealed off in an effort to locate the leak. “After the three days, there was no indication of where the leak was coming from,” Dorth said.

This latest test, he said, featured some “slightly different configurations” in both the U.S. and Russian segments, although he did not elaborate on the differences between the two tests. In addition, Cassidy used an ultrasonic leak detector to see if the leak was coming from Zvezda itself.

These tests were possible since mid-August because there were only three people on station, allowing them to be confined to one module for a period of time. Moreover, during this time no other spacecraft have arrived or left. It is suspected that the leak is most likely coming from the connection point between two modules, and adding or removing a Soyuz, Dragon, or freighter to the station shifts its center of gravity, changing the stress points at those connections.

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New study confirms liquid water under Mars’ south pole

3:02 pm

A new study has confirmed earlier work that suggested there were liquid lakes of water under the Martian south pole.

The data appears to indicate that the bodies are “hypersaline solutions” –a brine in which high concentrations of salt are dissolved in water – which is perhaps the reason they are able to stay liquid despite the very cold conditions of Mars’s south pole.

The fact that there is a whole set of lakes suggests that they have probably formed relatively easily, and that versions of them may therefore have been present throughout the history of the planet. [emphasis mine]

There is one problem with hypothesis indicated by the highlighted words. Mars’ rotational tilt (its obliquity) shifts significantly, from 0 to 60 degrees. Right now it is tilted about 25 degrees, similar to Earth. The south pole as we see it today will have been very different at different obliquities, which means there is no way to assume these posited underground lakes would have been there.

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Martian channels formed by water? by ice? by lava?

1:37 pm

Meandering channels on Mars
Click for full image.

Many of the pictures from Mars show meandering channels, all of which suggest an erosion process related to some form of flow. For most of the last half century, since the first images of these channels were beamed back by Mariner 9 in 1972, scientists had believed that liquid water must have caused them. The accumulating recent photos from Mars now tentatively suggest that these channels might have instead been caused by glacial processes, creeping frozen water instead of liquid.

The image to the right, rotated, cropped, and reduced to post here, was taken on July 17, 2020 by the high resolution camera on Mars Reconnaissance Orbiter. The channels suggest some form of flow going downhill to the northwest, but was it caused by water or ice? There is no obvious visual evidence of glaciers in this image, nor is there any such evidence that I can spot in any of the nearby high resolution images of this same region, despite the fact that at 35 degrees north latitude it is in the mid-latitude band where scientists have identified many glacial features.

The region itself is called Mareotis Fossae, an area of southwest-to-northeast trending parallel fissures and ridges, as shown in the two overview maps below.
» Read more

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China and Russia launch a bunch of satellites

8:40 am

Russia today used its Soyuz-2 rocket to launch three communication satellites plus 19 commercial smallsats.

This was the first time Russia used the Soyuz-2 for these particular small communications satellites, as previously they had been launched by a variety of smaller rockets.

China in turn today used its Long March 4B to place two Earth resource satellites into orbit.

The leaders in the 2020 launch race:

25 China
15 SpaceX
10 Russia
4 ULA
4 Europe (Arianespace)

China has moved ahead of the U.S. 25 to 24 in the national rankings.

These numbers should change again in the next few days. The U.S. has had a number of scrubs and launch delays in the past few days. ULA has been repeatedly pushing back the previously delayed launch of a National Security Agency reconnaissance satellite due to a variety of problems related to its Delta 4 Heavy rocket. The launch is now set for just after midnight tonight (Monday night). [UPDATE: Launch scrubbed due to lightning and poor weather. Tentatively rescheduled for 11:58 pm (Eastern) on September 29.]

SpaceX meanwhile had to scrub a launch this morning (September 28) of another 60 Starlink satellites due to weather. No new launch date has yet been announced.

Northrop Grumman also has had to scrub tomorrow’s Antares launch of a Cygnus cargo freighter because of poor weather at Wallops Island. It is now set for the evening of October 1st.

SpaceX also has a scheduled launch tomorrow morning of a GPS satellite on its Falcon 9 rocket. This is also threatened by weather. There is also no word whether the ULA launch scrub will cause this launch to be delayed.

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German instrument on Chang’e-4 documents dangerous radiation levels

2:07 pm

This result is not a surprise: A German instrument on China’s Chang’e-4 lander, located now on the Moon’s far side, has measured the radiation levels there, and found them to be much worse than found on Earth.

DLR radiation physicist Thomas Berger from the DLR Institute of Aerospace Medicine, who participated in the publication explains: “The radiation exposure we measured is a good indication of the radiation inside a spacesuit. The measurements give us an equivalent dose rate – the biologically weighted radiation dose per unit of time – of around 60 microsieverts per hour. For comparison, during a long-haul flight from Frankfurt to New York, the dose rate is five to 10 times lower than this. On Earth’s surface, it is some 200 times lower. In other words, a long-term stay on the Moon will expose astronauts’ bodies to high doses of radiation.”

“Human bodies are simply not made to be exposed to space radiation,” adds Robert Wimmer-Schweingruber of the Christian-Albrecht University (CAU) in Kiel, whose team developed and built the LND instrument . “On longer missions to the Moon, astronauts will have to protect themselves from it – by covering their habitat with a thick layer of lunar rock, for example. This could reduce the risk of cancer and other illnesses caused by long periods of time spent on the Moon.”

Previous instruments had only measured the cumulative radiation for the entire mission. This instrument took multiple readings lasting one, ten, or sixty minutes, which gives a more realistic measure of what an astronaut would actually experience, once there.

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An ice-covered mountain on Mars?

2:00 pm

Ice-covered mountain on Mars?
Click for full image.

Grinnell Crater in Glacier National Park in 2017

Today’s cool image, taken on July 1, 2020 by the high resolution camera on Mars Reconnaissance Orbiter, is of a mound-like mountain on Mars that to all intents and purposes appears covered by glacial ice, some eroded, some not.

The image to the right, rotated, cropped, and reduced to post here, shows this mound. Both the flow coming down from the mountain top down the north slope as well as the flow in the north that appears to begin in a small crater suggest glacial features.

Even more convincing are what appear to be patches of glacial ice on the southern slopes, resembling the kind of glacial patches you see everywhere in Glacial National Park. The second photo to the right, taken by me on our visit to Glacier National Park in 2017, shows similar patches hugging the mountainside at Grinnell Glacier.

This Martian mountain is located in the southern hemisphere inside Hellas Basin on its eastern interior rim. (See the overview map below, with the location of this photo the small white box south of Harmakhis Valles.) Thus, you would expect the north-facing slope to get more sunlight (and more heat) than the south-facing slopes. Yet, from this image there appears to be greater erosion on the south-facing slopes. A puzzle indeed.
» Read more

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Leak hunt continues on ISS

10:04 am

Two stories today indicate that the search for the elusive source of the slow leak on ISS is continuing.

The problem is that the two stories appear to have no overlap, making it hard to figure out what is planned and why.

The first story describes how engineers, based on the first isolation test, now think the leak must be coming from one of two modules:

…the ones the crew didn’t test because they were inside them while monitoring the rest of the station. One is the Zvezda Service Module, which provides life support for the station’s Russian side. The other is the Poisk Mini-Research Module 2, which serves as a port for docking spaceships and a place where crew members prepare for spacewalks.

The second story, from the Russian press, does not mention this detail. All it says is that the astronauts are going to once again isolate themselves in “the Russian segment” so the rest of the station can be tested for leaks. Since the two modules in question are both in that Russian segment, it is unclear where the astronauts will be isolated, especially since Zvezda is also where the Soyuz descent capsule is docked and if sealed from astronaut access it also seals them from their lifeboat.

It could be that the plan is to do another test of the American side of the station, then do these two Russian modules after the arrival of the next manned Dragon mission in a little less than a month. Dragon can then replace Soyuz as a lifeboat, allowing a test of Zvezda.

Regardless, the leak is a slow one, and is not yet life-threatening. That the leak rate has recently increased however requires action to find and fix it.

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SpaceX destroys Starship prototype #7, as planned

12:46 pm

Capitalism in space: SpaceX last night successfully pressurized its seventh Starship prototype to failure, as planned.

The culmination of three nights and more than 20 hours of concerted effort, SpaceX was finally able to fill Starship test tank SN7.1 with several hundred tons of liquid nitrogen before dawn on September 23rd. With just an hour left in the day’s test window, SpaceX closed the tank’s vents, allowing its cryogenic contents to boil into gas and expand with no outlet. At 4:57 am CDT, SN7.1 burst, bringing its lengthy test campaign to a decisive end.

I have embedded video of the test below the fold.

With the completion of this test the way is now clear for the 60,000 foot hop of Starship prototype #8, no earlier than October 11th.
» Read more

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Axiom, SpaceX, and NASA finalizing first wholly private manned mission

12:38 pm

Capitalism in space: Axiom, SpaceX, and NASA are close to finalizing the deal for the first wholly private manned mission to ISS, tentatively set for October 2021.

One of the topics Axiom is negotiating with NASA involves how much insight the space agency will have into the private astronaut mission. While the Axiom missions will be managed by commercial companies, the AX-1 flight will fly with a reusable Crew Dragon spacecraft that will carry NASA astronauts on other missions. “There’s a certain amount of insight (NASA) would like on our flight, on a commercial flight,” [Axiom official] Suffredini said Friday. “So that is one aspect of that process. We’re using a vehicle that is going to be re-flown, and NASA will certify the re-flights because they want to do re-flights.”

Axiom and SpaceX will also have to confirm a schedule with NASA for the AX-1 mission to dock with the space station. The orbiting research complex has a busy schedule of arriving and departing crew and cargo vehicles, and managers also have slot in spacecraft dockings amid spacewalks, experiments, and other critical operations.

NASA also oversees safety of the space station with the program’s international partners.

The private companies however will in the end be responsible for the flight.

There have been rumors that the passengers on this flight will be Tom Cruise and his film director, though this is not confirmed. Also, these same arrangements will be used for the tentative 2023 private flight of the winner of a proposed reality television show dubbed Space Hero.

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Blue Origin scrubs New Shepard flight today

12:21 pm

Capitalism in space: Blue Origin today scrubbed the first New Shepard flight in ten months.

From the company:

We’ve detected a potential issue with the power supply to the experiments. Launch is scrubbed for today. New launch target forthcoming.

Ten months since their last flight, and the power supply to the experiments has a problem the day of the launch? Sorry if I sound harsh, but that does not speak well for the company’s quality control systems.

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OSIRIS-REx team confirms date for sample grab from Bennu

12:16 pm

Nightingale landing site on Bennu
Click for full image.

The OSIRIS-REx science team has confirmed October 20, 2020 as the date the spacecraft will attempt a sample grab from the asteroid Bennu.

OSIRIS-REx is charged with collecting at least 2 oz. (60 grams) of Bennu’s rocky material to deliver back to Earth – the largest sample return from space since the Apollo program – and the mission developed two methods to verify that this sample collection occurred. On Oct. 22, OSIRIS-REx’s SamCam camera will capture images of the TAGSAM head to see whether it contains Bennu’s surface material. The spacecraft will also perform a spin maneuver on Oct. 24 to determine the mass of collected material. If these measures show successful collection, the decision will be made to place the sample in the Sample Return Capsule (SRC) for return to Earth. If sufficient sample has not been collected from [the primary landing site] Nightingale, the spacecraft has onboard nitrogen charges for two more attempts. A TAG attempt at the back-up Osprey site would be made no earlier than January 2021.

The press release at the link provides a lot of technical and interesting details about the sample-grab-and-go attempt, expected to put the spacecraft in contact with the asteroid’s surface for no more than sixteen seconds.

The maneuver itself is quite risky, as the available smooth landing area, as shown in the image above, is only half the size the equipment was designed for, and surrounded by large boulders.

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Corroding glacier in crater rim gully?

9:45 am

Gully in crater rim
Click for full image.

Today’s cool image to the right, rotated and cropped to post here, shows a gully flowing down the north facing rim of a 30-mile-wide crater in the southern cratered highlands. It was taken on June 30, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

To my eye the corroded ridges and pits running down the western side of this gully look like a corroded ice, as if we are looking at a glacier that the light of the Sun, which in the southern hemisphere hits this north-facing slope more directly and for longer periods of time, is causing it to sublimate away with time.

The wider shot below shows the entire rim, flowing downhill from the south to the north.
» Read more

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The first Starlink user test results

9:50 am

Capitalism in space: The first Starlink test results by actual users are finally coming out, and they suggest that the constellation will deliver very fast internet speeds indeed.

The article however reveals this tidbit that up until now SpaceX has managed to keep nicely obscured:

While Starlink will provide the kind of speeds and latency that should work for many services and games, Musk said the company simply won’t have the capacity to compete in major metro markets—a caveat often left unmentioned in Starlink coverage. “It’s not good for high-density situations,” Musk said. “We’ll have some small number of customers in LA. But we can’t do a lot of customers in LA because the bandwidth per cell is simply not high enough.”

As a result, Starlink won’t do much for the estimated 83 million Americans stuck under a broadband monopoly (usually Comcast), or the millions more whose only options are a duopoly; usually either the cable company or a sluggish DSL line from the local phone company.

In other words, the service will likely not be made available in dense urban areas, at least not initially.

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New Shepard test flight set for tomorrow

9:42 am

Capitalism in space: Blue Origin has scheduled a New Shepard test flight set for tomorrow morning at 10 am (Central), the first test flight in ten months.

This will be the seventh flight of this particular New Shepard spacecraft, the thirteenth overall for the program.

In March the company’s CEO had promised three flights by the end of 2020, with the last manned. The press release above howeveronly mentions that tomorrow’s test flight is the first of two, both now emphasizing how they will be flying payloads testing technology for lunar landings. No mention is made of a later manned mission.

It seems increasingly that Blue Origin is abandoning its suborbital space tourism business. If not, they sure don’t seem very enthusiastic about it any longer. Instead, they appear to be hyping New Shepard as a testbed for their effort to develop the manned lunar lander for NASA.

That same March update from the CEO had also said they would be initiating commercial production of their BE-4 rocket engine this year. All we have had so far is delivery of one testbed engine — not flightworthy — to ULA. ULA soon revealed there are problems with the engine.

All in all, Blue Origin is becoming less and less impressive, as time passes. Their suborbital tourism project appears to be abandoned. Their rocket engine has problems. And their New Glenn orbital rocket appears stalled.

All they have right now is their development contract with NASA to build a manned lunar lander, and in that case Blue Origin is only a minor player, even if the company is listed as the lead contractor. Their big partners (Lockheed Martin, Northrop Grumman, and Draper) will build the bulk of the lander, should NASA finally get the project financed by Congress.

The company’s failure to deliver so far is a true shame, as the company has ample finances, backed by Jeff Bezos’ billions.

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A patch of chaos in the Martian cratered southern highlands

1:12 pm

A patch of chaos in the southern cratered highlands of Mars
Click for full image.

Today’s cool image, rotated, cropped, and reduced to post here, takes us to the cratered southern highlands of Mars. Taken by the context wide angle camera on Mars Reconnaissance Orbiter, this image shows us a strange isolated patch of what appears to be chaos terrain, which on Mars generally means an area of random knobs and mesas cut by canyons and channels.

The large bulk of chaos terrain on Mars is found near or in the transition zone between the lowland northern plains and the southern cratered highlands, and is thought to have been created by slow erosion, possibly by glaciers. This erosion process is aided by the gradient downhill from those highlands to the lowlands.

This location however is in the middle of the cratered highlands, and shows no obvious slope in any direction. And though the location is in the mid-southern latitudes, there is no obvious evidence of glaciers among these knobs and mesas. Furthermore, the mesas are not all the same height. Instead, a large portion appear to have been shaved off, as if some giant came in with a putty knife and scrapped away at them.

This can be clearly seen by the close-up below, taken by MRO’s high resolution camera on July 16, 2002 of the area indicated by the white box, which for scale is about 2 1/4 miles square.
» Read more

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