Author: Robert Zimmerman

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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George Strait – Amarillo By Morning

6:06 pm

An evening pause:

I ain’t a dime but what I got is mine.
I’m not rich but Lord I’m free.

Hat tip to Robert Pratt of Pratt on Texas, who doesn’t know he suggested this. This song is something he plays for his guests during commercial breaks so they don’t have to listen to commercials. I decided after last Thursday’s appearance it needed to be an evening pause.

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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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UAE outlines new plans in space

8:57 am

The new colonial movement: The United Arab Emirates (UAE) had put forth a new set of goals in its space program, including sending another astronaut to space, sending an unmanned probe to the Moon, and encouraging the development of UAE-built Earth resource smallsats.

The lunar mission is targeted to launch in 2024, and it appears they wish to build it entirely themselves, rather than subcontract American companies and universities to do the bulk of the work, as they did for the Hope Mars orbiter. It appears they believe that the training their people got from the Hope mission development will make it possible for them to proceed now on their own.

I also suspect that instead of buying a Russian Soyuz launch, they are aiming to hire an American company, either SpaceX or Boeing, to fly their next astronaut, since they have made a deal with NASA for astronaut training.

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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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It WAS a coup attempt

2:51 pm

In the past few days a number of news stories have confirmed, unequivocally, that the effort in the FBI, CIA, and Justice Department to spy on the Trump campaign before the election and then pin the false accusation of Russian collusion on Trump after his election were all an effort to dictate the results of the election, and then overturn it when Trump won.

It was an out-and-out coup attempt by these government officials, apparently aided and abetted by Obama when he was still president.

First we learn that the FBI agents working on the fake prosecution of former National Security were so worried their misconduct would be uncovered by the Trump administration that they bought liability insurance to protect themselves.
» Read more

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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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