Year: 2019

Curiosity takes selfie next to two of its most important drill holes

3:04 pm

Curiosity and its most recent drill holes
Click for full image.

The Curiosity science team today released a beautiful mosaic of the rover, stitched from 57 different images. The photo at the right, cropped and reduced to post here, is the annotated version of that image. It shows the rover’s two most recent drill holes to the left. As the view looks away from Mount Sharp, you can see in the distance Vera Rubin Ridge, the floor of the crater, and its rim on the far horizon.

The two drill holes are significant because of the chemical experiment that Curiosity is subjecting the material from those holes.

The special chemistry experiment occurred on Sept. 24, 2019, after the rover placed the powderized sample from Glen Etive 2 into SAM. The portable lab contains 74 small cups used for testing samples. Most of the cups function as miniature ovens that heat the samples; SAM then “sniffs” the gases that bake off, looking for chemicals that hold clues about the Martian environment billions of years ago, when the planet was friendlier to microbial life.

But nine of SAM’s 74 cups are filled with solvents the rover can use for special “wet chemistry” experiments. These chemicals make it easier for SAM to detect certain carbon-based molecules important to the formation of life, called organic compounds.

Because there’s a limited number of wet-chemistry cups, the science team has been saving them for just the right conditions. In fact, the experiment at Glen Etive is only the second time Curiosity has performed wet chemistry since touching down on Mars in August 2012.

This time however was the first time they had used a wet chemistry cup on material from a drill hole. That they were able to do this at all is a testament to the brilliant innovative skills of the rover’s engineers. They had been holding off doing a wet chemistry analysis from drill hole material until they got to this point, but on the way the rover’s drill feed mechanism failed. It took more than a year of tests and experimentation before they figured out a way to bypass the feed mechanism by using the arm itself to push the drill bit into the ground. That rescue made possible the wet chemistry experiment that they initiated on September 24.

The results, which are eagerly awaited, won’t be available until next year, as it will take time for the scientists to analyze and publish their results.

Curiosity meanwhile has moved on, leaving this location where it had remained for several months to march in the past week southward back towards its long planned route up Mount Sharp.

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Big landslides on Mars might not require ice

1:49 pm

According to a new paper, scientists now think the biggest and longest landslides found on Mars might not require a base of ice on which it could slide such extensive distances.

The findings, published today in Nature Communications, show for the first time that the unique structures on Martian landslides from mountains several kilometres high could have formed at high speeds of up to 360 kilometres per hour due to underlying layers of unstable, fragmented rocks.

This challenges the idea that underlying layers of slippery ice can only explain such long vast ridges, which are found on landslides throughout the Solar System.

First author, PhD student Giulia Magnarini (UCL Earth Sciences), said: “Landslides on Earth, particularly those on top of glaciers, have been studied by scientists as a proxy for those on Mars because they show similarly shaped ridges and furrows, inferring that Martian landslides also depended on an icy substrate. “However, we’ve shown that ice is not a prerequisite for such geological structures on Mars, which can form on rough, rocky surfaces. This helps us better understand the shaping of Martian landscapes and has implications for how landslides form on other planetary bodies including Earth and the Moon.”

The lighter gravity of Mars, about one third of Earth’s, is part of the explanation, though many other factors are involved. Either way, this is one more data point in the evidence that the though geology on Mars might look like what we see on Earth, it is likely very different than we expect, due to the alien nature of Mars itself.

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New estimate for Hubble constant differs from previous and also conflicting results

11:55 am

The uncertainty of science: Using microlensing effects scientists have measured a new estimate for the Hubble constant, the rate in which the universe is expanding, and have come up with a number that is different from previous results.

Using adaptive optics technology on the W.M. Keck telescopes in Hawaii, they arrived at an estimate of 76.8 kilometers per second per megaparsec. As a parsec is a bit over 30 trillion kilometers and a megaparsec is a million parsecs, that is an excruciatingly precise measurement. In 2017, the H0LICOW team published an estimate of 71.9, using the same method and data from the Hubble Space Telescope.

The new SHARP/H0LICOW estimates are comparable to that by a team led by Adam Reiss of Johns Hopkins University, 74.03, using measurements of a set of variable stars called the Cepheids. But it’s quite a lot different from estimates of the Hubble constant from an entirely different technique based on the cosmic microwave background. That method, based on the afterglow of the Big Bang, gives a Hubble constant of 67.4, assuming the standard cosmological model of the universe is correct.

An estimate by Wendy Freedman and colleagues at the University of Chicago comes close to bridging the gap, with a Hubble constant of 69.8 based on the luminosity of distant red giant stars and supernovae.

So five different teams have come up with five different numbers, ranging from 67.4 to 76.8 kilometers per second per megaparsec. Based on the present understanding of cosmology, however, the range should have been far less. By now the physicists had expected these different results to be close to the same. The differences suggest that either their theories are wrong, or their methods of measurement are incorrect.

The most likely explanation is that we presently have too little knowledge about the early universe to form any solid theories. These measurements are based on a very tiny amount of data that also require a lot of assumptions.

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Mice in space and kept in artificial gravity experience no harm to reproduction

11:43 am

The uncertainty of science: Male mice who spent thirty-five days on ISS but within a centrifuge that created 1 g of artificial gravity apparently experienced no damage to their ability to reproduce.

This project team developed a habitat cage unit (HCU) capable of being installed in the Centrifuge-equipped Biological Experiment Facility (CBEF) on the ISS. The mice were placed under artificial gravity or microgravity (by centrifugation). After their return to Earth, they were compared with a “ground control” raised on the ground for the same 35-day period. (Fig.1)

The joint team found that: [1] The sperm production ability and the sperm fertilizing ability of the mice returned to Earth were normal, compared to the ground control and, [2] offspring of the mice sent to outer space was healthy and there were no effects on their reproduction ability from their parents’ stay in outer space.

While this study suggests that some form of artificial gravity can possible mitigate some of the risks to reproduction in space, there are so many unknowns that it at this point it leaves more questions than it answers.

  • Would an artificial gravity less than 1 g accomplish the same thing?
  • Would no gravity cause damage? According to the study, this is not yet known.
  • What about insemination? Would it proceed with no problems in space?
  • What about female reproduction? Will artificial gravity mitigate issues for them?

I could go on. I almost wish they had done this experiment first in zero gravity, to see its effects, before proceeding to an artificial gravity environment.

Nonetheless, these results do suggest that reproduction in space will be possible, as long as an artificial gravity of some kind is provided.

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Israel still aims for second attempt to land on Moon

11:26 am

According to an official with Israel’s government-owned aerospace manufacturer, Israel is still planning a second Beresheet mission to land an unmanned probe on the Moon, despite the failure of Beresheet earlier this year.

But despite the hard landing, Israel has no intent to stop chasing the moon, Hayun said. (Shortly after the crash, the SpaceIL organization behind the mission suggested it would target a different destination than the moon; it’s unclear what will happen on that front.) The team behind Beresheet has mostly stayed on, he said during his presentation, and they intend to fly a new version of the lander within two or 2.5 years.

The successor spacecraft would include some design tweaks meant to increase the mission’s odds of landing softly. New versions will carry upgraded computers and, unlike the original Beresheet spacecraft, will be armed with an obstacle-avoidance system for landing. But Israel’s future landers will still be compact and still work with rideshare launches, Hayun said.

As much as I sincerely hope this happens, I am somewhat skeptical. First of all, a number of key Israeli engineers left SpaceIL to form a partnership with the U.S. company Firefly. Second, this presentation appears to have been very vague on where they intend to get their funding. If anything, it appears to be a sales effort to find that money.

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Mars2020 budget overruns threatening other missions

11:18 am

The significant budget overruns for NASA’s Mars 2020 mission, now expected to exceed a billion dollars, could now pose a threat to other planetary projects.

The cost of Mars 2020 has been growing for a while. The initial proposed cost for the rover, when the mission was announced in 2012, was $1.5 billion. Six years on, a 2018 Government Accountability Office (GAO) report showed that the cost had soared to $2.46 billion. And in NASA’s latest budget, the overrun looks set to grow by as much as 15% (or about another $360 million) beyond that last 2018 estimate, although the latest numbers are yet to be confirmed.

The irony is that Mars 2020 was established by the Obama administration as part of its effort to significantly cut back on NASA’s entire planetary program. The idea was to save money by simply rebuilding Curiosity.

As is typical for these projects, the scientists pushed for cutting edge instruments, and it is these instruments that have caused the overages. Meanwhile, many of those 2012 cuts pushed by Obama never happened, or were simply funneled into different planetary projects that were approved later.

No one who is involved in any way with the U.S. government today knows anything about keeping their effort on budget and on time. No one. And the result is increasing debt and what will certainly be bankruptcy for everyone, at some point, thus causing everything to shut down.

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Synchronized cavern diving

6:01 pm

An evening pause: They call this a flash mob, but that’s not accurate. These divers did not mysteriously appear here to move in unison in order to surprise someone. They all planned it together.

Nonetheless where they are and what they do is beautiful. I especially like when they coordinate the pointing of their dive lights.

Hat tip Mike Nelson.

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Judge rules civil forfeiture is unconstitutional

5:02 pm

A South Carolina judge has ruled that the use of civil forfeiture against individuals is unconstitutional and must cease.

Circuit Judge Steven H. John has ruled that the South Carolina’s civil asset forfeiture regulations violate the Fifth, Eighth, and Fourteenth Amendment rights of the citizens.

…Judge John notes all of these problems in a decisive ruling that smacks down the practice of civil asset forfeiture. In his 15-page opinion, he writes that South Carolina’s forfeiture practice violate both the U.S. Constitution and the state’s because the statutes “(1) place the burden on the property owner to prove their innocence, (2) unconstitutionally institutionally incentivizes forfeiture officials to prosecute forfeiture actions, and (3) do not mandate judicial review or judicial authorization prior to or subsequent to the seizure.” He also notes that the statutes violate citizens’ Eighth Amendment protections against excessive fines.

This is plain common sense, and an easy conclusion if one simply reads the unmistakable words in the Constitution. Unfortunately, decisions like this have so far been relatively rare. Hopefully this decision will start a trend.

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India releases first radar images from Chandrayaan-2

12:45 pm

Radar image from Chandrayaan-2
Click for full image.

India yesterday released the first radar images produced by its lunar orbiter, Chandrayaan-2, the best such images yet produced by any spacecraft. As their press release notes:

Synthetic Aperture Radar (SAR) is a powerful remote sensing instrument for studying planetary surfaces and subsurface due to the ability of the radar signal to penetrate the surface. It is also sensitive to the roughness, structure and composition of the surface material and the buried terrain.

Previous lunar-orbiting SAR systems such as the S-band hybrid-polarimetric SAR on ISRO’s Chandrayaan-1 and the S & X-band hybrid-polarimetric SAR on NASA’s LRO [Lunar Reconnaissance Orbiter], provided valuable data on the scattering characterisation of ejecta materials of lunar impact craters. However, L & S band SAR on Chandraayan-2 is designed to produce greater details about the morphology and ejecta materials of impact craters due to its ability of imaging with higher resolution (2 – 75m slant range) and full-polarimetric modes in standalone as well as joint modes in S and L-band with wide range of incidence angle coverage (9.5° – 35°). In addition, the greater depth of penetration of L-band (3-5 meters) enables probing the buried terrain at greater depths. The L & S band SAR payload helps in unambiguously identifying and quantitatively estimating the lunar polar water-ice in permanently shadowed regions.

The image on the right, cropped and reduced to post here, is from one of the two images released. The brighter areas indicate rougher terrain as well as the location of ejecta from the crater, some of which is below the surface and is not obvious in optical images.

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China officially withdraws extradition bill that sparked Hong Kong protests

10:14 am

The Chinese government has now officially withdrawn the extradition bill that would have allowed Hong Kong citizens to be tried within China and that triggered the on-going Hong Kong protests.

We will have to see if this defuses the situation. The protesters have put forth other demands, such as calling for an investigation of the Hong Kong police, instigated by their sometimes violent behavior in response to the protests. More important, the protests have also demanded the return of real elections to Hong Kong, something the Chinese government eliminated in recent years.

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Bhabha Crater at dawn

9:53 am

Central peaks of Bhabha Crater at dawn

Cool image time! The Lunar Reconnaissance Orbiter (LRO) science team have released a beautiful oblique image of Bhabha Crater, located on the Moon’s far side, taken just as dawn was breaking over the crater’s central peaks.

The image to the right is a section of that picture, showing the central peaks near the bottom with the western rim of the 50-mile-wide crater at the top. The giant shadows of those central peaks can be seen extending across the floor of the crater and against that western rim. The photograph was taken on August 28, 2019 from an altitude of about 45 miles. The area of the central peaks in daylight is estimated to be about nine miles across.

The LRO science team releases a new press release image about once every two weeks. I suspect that they hoped this release would have shown the location of India’s Vikram lander. As they are as yet unable to find it, they instead provided us this cool image instead.

If you go to the link you can use their viewer to view and explore this very very large image. For example, if you zoom into those central peaks you can actually see small boulders scattered across their rounded tops.

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UK hypersonic engine component passes test

9:33 am

An important component of the hypersonic engine being developed by Reaction Engines, a private company based in the United Kingdom, has successfully passed a major test.

UK company Reaction Engines has tested its innovative precooler at airflow temperature conditions equivalent to Mach 5, or five times the speed of sound. This achievement marks a significant milestone in its ESA-supported development of the air-breathing SABRE engine, paving the way for a revolution in space access and hypersonic flight.

The precooler heat exchanger is an essential SABRE element that cools the hot airstream generated by air entering the engine intake at hypersonic speed.

This is good news for the company and the engine, but don’t expect to buy a ticket on a spaceship using SABRE anytime soon. This success is only a beginning. They remain a long way from flight.

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