Gil Levin passes away

Gil Levin, a instrument project scientist for one of the science experiments on the Mars Viking landers in the 1970s, has passed away at 97.

Levin deserves special mention because he believed for years that his experiment, called “labeled release,” had possibly found evidence of life.

Dr. Levin’s experiment employed a nine-foot arm to scoop Martian soil into a container, where it was treated with a solution containing radioactive carbon nutrients. Monitors detected the release of radioactive gas, which Dr. Levin interpreted as evidence of metabolism.

“Gil, that’s life,” Straat said when they saw the results.

The findings held true for both Viking 1 and Viking 2, which took samples from different regions of the planet. Other experiments aboard the Viking, however, used different methods to conclude that Martian soil did not contain carbon, an element found in all living things.

Dr. Levin stood by his findings, but top NASA scientists disagreed, saying that the response he observed was the result of inorganic chemical responses, not biological processes. “Soon thereafter,” Dr. Levin told the Johns Hopkins University School of Engineering Magazine last year, “I gave a talk at the National Academy of Sciences saying we detected life, and there was an uproar. Attendees shouted invectives at me. They were ready to throw shrimp at me from the shrimp bowl. One former adviser said, ‘You’ve disgraced yourself, and you’ve disgraced science.’”

I met Levin once and interviewed him several times. With amazing grace and cheerfulness he always emphasized that his results needed to be confirmed, and there was certainly room for skepticism, but to reject them outright was not how the scientific method worked.

Levin however was never awarded another NASA project, essentially blackballed because of his 1970s claims, even though later research hinted at the possibility that he may have been right.

R.I.P. Gil Levin. Though the overall data we have gotten from Mars in the half century since still favors a non-life explanation for his experiment, the uncertainty remains quite large. He could have been right.

More important than his uncertain result, however, was his dedication to the proper scientific method, where you let the data speak for itself and never dismiss any possibility if that is what the data shows you.

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Superheavy prototype #4 rolls to orbital launchpad

Superheavy #20 on the way to launchpad

Superheavy on launchpad
Click for live stream.

Capitalism in space: SpaceX today rolled its 4th Superheavy prototype from its assembly building in Boca Chica, Texas, moving it to the orbital launchpad in preparation for having the 20th Starship prototype stacked on top and assembled for the rocket’s first orbital test flight.

The first image to the right is a screen capture taken from a short movie posted in an Elon Musk tweet. It shows the base of this Superheavy, with its 29 Raptor engines. The engines appear surrounded by the support structure that holds the stage to the truck mover.

The second image to the right is a screen capture from Labpadre’s live stream Saphire camera, captured shortly before this post was published. Superheavy is 230 feet tall. Starship is 165 feet tall. Combined that equals just under 400 feet, which is still about 30 feet taller than the Saturn-5.

Yet, Superheavy is easily dwarfed by the launch tower behind it, and when they stack Starship on top the combined rocket will still be only three quarters as tall as the tower. They are using that tower not only for launches, but for stacking of Starship as well as a capture devise for when later Superheavies return to Earth. Instead of having landing legs, Superheavy will eventually lower itself into position next to the tower and hover there so that the tower can grab it.

All this means the tower needs to be taller than the combined rocket. I would also expect that a second tower will be necessary eventually for that landing grab.

Before they stack Starship #20 on top they will likely do pressure and tank tests of Superheavy, and maybe a few dress rehearsal countdowns leading to short static fire tests.

It still appears to me that we are looking for an orbital test flight sometime in late September, early October.

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Chinese pseudo-private rocket fails during launch

A launch attempt by the pseudo-private Chinese company iSpace failed today, the second failure in a row for this company following a success.

A Hyperbola 1 rocket lifted off from the Jiuquan launch base at 3:39 a.m. EDT (0739 GMT; 3:39 p.m. Beijing time), China’s government-run Xinhua news agency said. Xinhua, which described the launch as a “flight test,” said the rocket exhibited “abnormal performance” after liftoff. Officials did not immediately specify when during the flight the rocket failed.

The news agency said a satellite carried by the rocket “did not enter orbit as scheduled.” Chinese officials did not identify the payload lost on the mission.

This is the second launch failure in a row, following the first successful orbital launch in July 2019.

The rocket is made of four solid-fueled stages, which means it most certainly is using military tecnology and is being closely supervised by the Chinese government. ISpace is one of about four such pseudo-private Chines companies. In each case, China is allowing private Chinese capital to finance the development of these rockets, for use both by the Chinese government as well as sale to customers (but only with the government’s approval and control).

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Curiosity’s wheels: a good news update

Curiosity's wheels
Click here and here for the original images.

For the past few weeks Curiosity has been traveling across some of the roughest terrain it has seen on Mars, since landing in Gale Crater in August 2012. The rover is now roving among the high cliffs and foothills at the very base of Mt Sharp, with the ground covered with rocks, boulders, plates of bedrock, and all sorts of protrusions.

On August 1st the rover team used its cameras to do another survey of the rover’s wheels to see how they fared during that journey. The two images to the right compare the same area on the same wheel after the most recent 16 sols of travel. This is the same wheel I have focused on since 2017. Overall, the damage in the most recent picture seems almost identical to the previous picture. In fact, if you compare today’s image with the annotated version of the 2017 photo, found here, you can see how little things have changed since then.

From this one wheel it appears that the wheels are continuing to hold up quite well. The Curiosity team of course needs to review all the images of all the wheels, but based on this one comparison, it looks like their long term strategies for mitigating damage to the wheels is working, even in the rough terrain the rover is presently traversing.

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Martian lava flooded crater?

lava flooded crater?
Click for full image.

A quick cool image! The photo to the right, rotated, cropped and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) more than a decade ago, on June 1, 2010. I post it now because it is today’s MRO picture of the day, and is definitely cool. The caption:

One of a few “scaly-looking” inselbergs within regional platy-ridged flows in Elysium Planitia. This inselberg has a broken and blocky appearance with some of the blocks being tilted. Could this be the remnant of a once extensive mantling deposit? An inselberg is an isolated hill or mountain rising abruptly from a plain.

The wider image by MRO’s context camera below, also rotated, cropped and reduced to post here, illustrates even more forcefully how isolated this circular set of blocks is.
» Read more

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Two flybys of Venus set by two spacecraft on August 9th and 10th

Two European planetary probes, one launched to study the inner solar enviroment and the second to study Mercury, are going to fly past Venus only 33 hours apart on August 9th and 10th.

Solar Orbiter, a partnership between ESA and NASA, will fly by Venus on 9 August with a closest approach of 7995 km at 04:42 UTC. Throughout its mission it makes repeated gravity assist flybys of Venus to get closer to the Sun, and to change its orbital inclination, boosting it out of the ecliptic plane, to get the best – and first – views of the Sun’s poles.

BepiColombo, a partnership between ESA and JAXA, will fly by Venus at 13:48 UTC on 10 August at an altitude of just 550 km. BepiColombo is on its way to the mysterious innermost planet of the solar system, Mercury. It needs flybys of Earth, Venus and Mercury itself, together with the spacecraft’s solar electric propulsion system, to help steer into Mercury orbit against the immense gravitational pull of the Sun.

The two spacecraft will zip past a different side of Venus. For a variety of reasons, the imagery gathered will not of high resolution, though both spacecraft will gather data that will eventually be correlated with similar data being gathered by Japan’s Akatsuki probe, in orbit around Venus since 2015.

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SpaceX installs 29 Raptor engines on Superheavy #4

Capitalism in space: SpaceX has now installed 29 Raptor engines on the fourth Superheavy prototype, intended to be the first to attempt an orbital launch, even as the company also prepares Starship prototype #20 for that flight.

In a marked increase to the already-impressive production cadence at SpaceX Starbase, it’s all hands on deck with Booster 4 and Ship 20 preparations ahead of the duo being sent to the launch site. Booster 4 was stacked on Sunday, with all 29 Raptors installed by Monday morning. While the orbital launch attempt is not imminent, the duo is expected to undergo a series of ground testing objectives, including multiple Static Fire tests for the booster. This will also provide time to complete the final elements of the Orbital Launch Site (OLS), from which the duo will conduct the milestone test flight.

Following a short ground testing campaign with Booster 3, which included cryo proofing and a three-engine Static Fire test, the focus is now on what will become the first integrated stack of a Super Heavy booster and a Starship vehicle. This is set to be achieved in double-quick time, following a call to arms from SpaceX to its workforce. This included the transportation of hundreds of workers from other sites in the country, as per a memo leaked on Facebook.

As predicted, SpaceX did not succeed in launching Superheavy/Starship on its first orbital test flight in August. However, as predicted the company is clearly pushing to attempt that flight before the end of the summer. Right now, based on the pace of operations, what has been accomplished, and what needs to be accomplished, I estimate that flight will likely occur sometime around late September to early October.

It also seems very obvious that SpaceX is trying very hard to beat SLS into orbit. If successful, it will underline most starkly the difference between free enterprise and government operations. The former got it done in about four years, for less than $6 billion. The latter has taken seventeen years, and about $60 billion, and has still not launched.

And even if SLS launches first, that contrast remains.

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Starliner launch scrubbed; no launch date yet set

For reasons that have not yet been revealed, ULA scrubbed today’s unmanned demo test flight of Boeing’s Starliner capsule just prior to launch, rescheduling the launch for tomorrow.

The launch tomorrow wiill occur at 12:57 am (Eastern).

UPDATE: It appears the scrub occurred because of a valve issue in the propulsion system of Boeing’s Starliner capsule.

“During pre-launch preparations for the uncrewed test flight of the CST-100 Starliner spacecraft, Boeing engineers monitoring the health and status of the vehicle detected unexpected valve position indications in the propulsion system,” the company said in a statement. “The issue was initially detected during check outs following yesterday’s electrical storms in the region of Kennedy Space Center.”

…The propulsion system valves in question are inside the Starliner’s service module, which has an array of rocket thrusters designed to propel the spacecraft away from its launcher during an in-flight emergency. Other thrusters on the service module are used for in-orbit maneuvers and spacecraft pointing control.

Boeing cannot afford more failures during this second demo flight. The company has been plagued with numerous debilitating technical failures during the past four years, from Starliner to its airlines. Right now the failure to get Starliner operational is losing them business in the emerging orbital tourist market. They need to get it working, and working reliably.

UPDATE: They have decided to cancel the launch plans for tomorrow, to roll the rocket back into the assembly building so they can do more tests on the capsule’s service module where the troublesome valves are.

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Nauka shook up ISS more than first revealed

According to new reporting, when the new Russian module Nauka unexpectedly began firing its engines, it rotated the International Space Station far more than first revealed, requiring a much more complicated effort to bring the station back to its correct orientation.

Zebulon Scoville, the flight director at NASA mission control in Houston, revealed that the 45 degrees that was initially reported as the amount ISS rotated was incorrect.

According to Scoville, the event has “been a little incorrectly reported.” He said that after Nauka incorrectly fired up, the station “spun one-and-a-half revolutions — about 540 degrees — before coming to a stop upside down. The space station then did a 180-degree forward flip to get back to its original orientation,” according to the report.

Scoville also shared that this was the first time that he has ever declared a “spacecraft emergency.”

It appears that though the station spun far more than first reported, the rate of rotation was still relatively slow, so it apparently did no harm to the station.

Scoville also revealed that, based on the data on hand during the event, it appeared Nauka was also trying to undock itself from the station. Mission controllers tried to counter this by firing engines on a Russian Progress freighter as well as on the Zvezda module.

Had Nauka’s engines had not stopped firing (for unknown reasons, though probably because they ran out of fuel), there was the real chance the accelerations could have shaken the station apart. Moreover, that other engines were brought into play suggests that the Russians not only did not know why Nauka’s engines fired, they had at the time no way to shut them down, and were thus forced to improvise other actions to try to save the increasingly dangerous situation.

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The sublimating surface of Mars’ northern plains?

Sublimating patches on Mars?
Click for full image.

Cool image time! The photograph to the right, cropped and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter on May 27, 2021. A sample image, likely taken not as part of any specific scientist’s research but by the camera team in order to maintain the camera’s temperature, shows an area of the Martian northern plains that appears filled with rough scattered depressions, possibly caused by sublimation of buried ice.

The location, at 54 degrees north latitude, is far enough north to easily have a lot of buried ice. It is also only about 40 miles to the east of Milankovič Crater, where scientists have found many scarps that appear to have exposed layers of ice in their cliff faces.

However, the location has other components that must raise questions about this sublimating ice hypothesis.
» Read more

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Upcoming Zimmerman public lecture available for all – Last Call!

Tomorrow I will be giving a lecture on the Artemis Accords to the Arizona Space Business Roundtable, a monthly event in Tucson, founded by space businessman and local all-around good guy Stephen Fleming, to bring together the business-oriented space community of this city and southern Arizona.

From Stephen Fleming’s announcement:

Bob has spoken to the Roundtable before; this time, I’ve asked him to focus on the Artemis Accords… the USA’s attempt to “to create a safe and transparent environment which facilitates exploration, science, and commercial activities for all of humanity to enjoy.” What does that mean? It’s an attempt to break the international logjam that has blocked the private sector development and exploitation of resources on the Moon, asteroids, and other celestial bodies. How is it working, who has joined on, and what does China think about all this? Come find out from Bob!

The event will be open to the public, no charge, and will also be available on Zoom. It is scheduled for Tuesday, August 3, 2021, from 5:00 — 6:30 pm (Arizona time, which presently corresponds to Pacific time).

If you wish to come in person, the event will be at 110 E. Pennington St, Room 215, in Tucson.

If you want to attend via Zoom, you will need to express your interest as a comment below, and I will then email you the Zoom url and password. We are not publishing this information publicly to avoid a hacking during the event.

Let me repeat: You need to express an interest in attending by Zoom by posting a comment. Otherwise you will not get the password and will not be able to watch. (I will send out the password tomorrow to all those in the comment thread.)

If you are coming in person Stephen would appreciate it if you say so in a comment below also, so that he can estimate a count. He provides, out of his own pocket, cookies and coffee for in-person attendees, and needs to gauge how much to provide.

Note that I have written these essays previously about other Arizona Space Roundtable events:

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Sunspot update: Another month of greater activity than predicted

NOAA this past weekend released an update of its monthly sunspot cycle graph, showing the Sun’s sunspot activity for the past month. That graph is below, annotated to show the previous solar cycle predictions and thus provide context.

In July the Sun’s hot streak of sunspot activity continued. The number of sunspots on its visible hemisphere continued to exceed the prediction of NOAA’s solar science panel, with the numbers in July easily topping June’s numbers. Only at the very end of July was there a streak of five blank days, the first time the Sun has been blank of sunspots since May 6th, a stretch of activity not seen for years, since the last solar maximum was ramping down to solar minimum in ’16-’17.

The political consequences of this continuing high activity could be quite profound.
» Read more

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