Tag: science

InSight hits a rock

8:36 am

Engineers have called a pause in InSight’s drilling operation to insert a heat sensor as much as 16 feet into the Martian soil because it appears the drill has hit a large obstruction.

It penetrated to a depth between 18cm and 50cm into the Martian soil with 4,000 hammer blows over a period of four hours, explained Tilman Spohn, HP3’s principal investigator from the German space agency (DLR). “On its way into the depths, the mole seems to have hit a stone, tilted about 15 degrees and pushed it aside or passed it,” he added. “The mole then worked its way up against another stone at an advanced depth until the planned four-hour operating time of the first sequence expired.”

Prof Spohn said there would now be a break in operations of two weeks while the situation was assessed.

When these facts were first reported on March 1st, the press release did not make it clear at that time that the hammer drill was actually blocked. If it cannot drill down further, this will put a crimp in the heat sensor’s ability to measure Mars’s internal temperature. Right now it is only about a foot down, which on Earth would still have it influenced by surface temperatures.

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Possible cure for AIDS?

9:17 pm

In the past week researchers have revealed that two different patients have apparently had the AIDS HIV virus eliminated from their bodies.

The virus infects cells of the immune system, which are made in the bone marrow. A man known as the “Berlin patient” was the first person to become HIV-free after cancer treatment, back in 2007. To treat his leukaemia – a cancer of the immune system – he was given a treatment that involved killing nearly all his immune cells with radiotherapy or drugs, and then replacing them with cells from a donor. This donor was naturally resistant to HIV, thanks to a rare but natural mutation in a gene called CCR5.

Since then, no one else had had HIV eliminated from their body in the same way, until a second case was announced on Monday. This person, known as the London patient, was given bone marrow from a donor with the CCR5 mutation as a treatment for Hodgkin’s lymphoma, another immune cell cancer. He was advised to stop taking the antiviral drugs that keep the virus in check about a year afterwards. Eighteen months later, the virus hasn’t returned.

A possible third case was then announced today, at the Conference on Retroviruses and Opportunistic Infections in Seattle.

The more than dozen year gap between the first cure and the two this week is partly because it takes so long to perform the treatment and then confirm the virus is gone. Moreover, this treatment can only be given to a limited number of patients, because of the risks involved.

Nonetheless, if this cure is proven viable, it will be a great triumph for modern science.

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New method to turn CO2 into coal

1:42 pm

Scientists have developed a new relatively low-cost method for turning atmospheric carbon dioxide into solid carbon that then be used as a synthetic fuel.

“By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scaleable,” [Dr. Torben Daeneke, a research scientist at RMIT University.] said. The liquid metal catalyst was developed by the researchers with specific surface properties, making it extremely efficient at conducting electricity, while chemically activating the surface.

According to the press release: “The carbon dioxide is dissolved in a beaker with an electrolyte liquid and a small amount of the liquid metal, which is then charged with an electric current. The CO2 slowly converts into solid flakes of carbon, which are naturally detached from the liquid metal surface, allowing the continuous production of carbonaceous solid.”

And, yes, the process has the potential to yield a future energy source. The carbon produced may be able to be used as an electrode.

This is excellent news, for a lot of reasons. At the same time, I always find this effort to use technology to grab and convert atmospheric carbon dioxide somewhat ironic. We already have a very efficient biological tool for doing this, called plant life, which is presently thriving worldwide because of the increased CO2 in the atmosphere. The more you plant, the more oxygen you create. And what’s more, it gives you a lot more food to eat. Why do anything else?

Hat tip reader John Vernoski.

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New analysis suggests photon could make dark matter unnecessary

1:28 pm

The uncertainty of science: A new analysis by physicists that assumes a very very low mass for the photon, the particle that transmits light, could very well explain the motions of stars in galaxies and make dark matter unnecessary.

Professor Dmitri Ryutov, who recently retired from the Lawrence Livermore National Laboratory in California, USA, is an expert in plasma physics. He was awarded the American Physical Society’s (APS) 2017 Maxwell Prize for Plasma Physics for his achievements in the field. Physicists generally credit Ryutov with establishing the upper limit for the mass of the photon. As this mass, even if it is nonzero, is extremely small, it is usually ignored when analyzing atomic and nuclear processes. But even a vanishingly tiny mass of the photon could, according to the scientists’ collaborative proposal, have an effect on large-scale astrophysical phenomena.

While visiting Johannes Gutenberg University Mainz (JGU), Ryutov, his host Professor Dmitry Budker of the Helmholtz Institute Mainz (HIM), and Professor Victor Flambaum, Fellow of the Gutenberg Research College of Mainz University, decided to take a closer look at the idea. They were interested in how the infinitesimally small mass of the photon could have an effect on massive galaxies. The mechanism at the core of the physicists’ assumption is a consequence of what is known as Maxwell-Proca equations. These would allow additional centripetal forces to be generated as a result of the electromagnetic stresses in a galaxy.

Are the effects as strong as those exerted by dark matter?

“The hypothetical effect we are investigating is not the result of increased gravity,” explained Dmitry Budker. This effect may occur concurrently with the assumed influence of dark matter. It may even – under certain circumstances – completely eliminate the need to evoke dark matter as a factor when it comes to explaining rotation curves. Rotation curves express the relationship between the orbital speeds of stars in a galaxy and their radial distance from the galaxy’s center. “By assuming a certain photon mass, much smaller than the current upper limit, we can show that this mass would be sufficient to generate additional forces in a galaxy and that these forces would be roughly large enough to explain the rotation curves,” said Budker. “This conclusion is extremely exciting.” [emphasis mine]

They readily admit that this first analysis is very preliminary, and causes some additional theoretical problems that conflict with known data. Nonetheless, this simple idea could eliminate the need for the additional dark matter particle that physicists have had trouble explaining or even finding.

In fact, I am somewhat baffled why physicists had not proposed this decades ago. It provides a much more straightforward explanation for the higher rotational curves in the outer parts of galaxies, and does not require any new physics.

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New project to map shallow water sources on Mars

1:13 pm

Scientists at the Planetary Science Institute (PSI) in Arizona have begun a new project to map the near-surface ice deposits in the low elevation regions of the Martian northern hemisphere.

Two teams led by Putzig and Morgan were contracted by NASA to pursue separate mapping efforts of subsurface ice deposits in Arcadia Planitia. After their mid-term reports showed significant synergy, the teams were combined in a joint project called “Subsurface Water Ice Mapping (SWIM) on Mars,” which extends the coverage of the mapping project from an experimental swath over Arcadia Planitia to all other low elevation regions across the Martian Northern Hemisphere. “Water ice will be a critical resource for human explorers on Mars, not only for life support but also for generating fuel to power equipment on the ground and rockets for the return journey to Earth,” said Putzig, a Senior Scientist at PSI. “Maps that identify the nature and availability of potential water resources will help determine where humanity will establish its first outposts on Mars.”

The SWIM team is producing new maps of the likelihood of subsurface ice deposits over these regions by combining radar, thermal, neutron, altimetry, and image data from several Mars-orbiting spacecraft. The team is also employing newly developed techniques that include using radar returns to infer the presence of ice within the top 5 meters of the crust and applying advanced radar processing to improve resolution at depth and to estimate the purity of ice in the subsurface.

Unlike most planetary research, this project is not aimed specifically at understanding the geology of Mars. Instead, it appears focused on the needs of future human exploration and settlement, finding easily accessible water sources in the northern hemisphere of Mars. The spots they identify will likely be the first Martian real estate of significant value.

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NASA cancels overbudget instrument for Europa clipper

8:36 am

Because its budget had ballooned to three times its original estimate, NASA has decided to cancel a science instrument for its Europa Clipper probe to Jupiter’s moon.

[Thomas Zurbuchen, NASA associate administrator for science] said in the memo that, at the time of the February review, ICEMAG’s estimated cost has grown to $45.6 million, $16 million above its original cost trigger and $8.3 million above a revised cost trigger established just a month earlier. That cost was also three times above the original estimate in the ICEMAG proposal. “The level of cost growth on ICEMAG is not acceptable, and NASA considers the investigation to possess significant potential for additional cost growth,” Zurbuchen wrote in the memo. “As a result, I decided to terminate the ICEMAG investigation.”

The contrast between how NASA operates in its unmanned planetary science programs with how the agency operates in its manned programs is striking. The agency’s planetary program is probably its most successful achievement, and has been for decades. Spacecraft almost always get built close to budget, launch on time, and accomplish amazing things when their arrive at their planetary targets, either the Moon, Venus, Mars, Jupiter, Saturn, or Pluto and beyond. Part of the reason for this success is a willingness by NASA to make hard decisions, such as the one above, even if it might ruffle some political feathers. The result is that everyone focuses on getting the job done, on budget and on time. They know that if they screw up, as the ICEMAG team did here, they might find themselves on the chopping block.

In contrast, as I noted in my previous post, NASA allows things to get out of control in its manned program. In fact, they might consider this a feature of the system, not a bug. The goal is not to accomplish anything, but to funnel cash to the states and districts of elected officials. The result is that nothing ever flies, or if it does, it does so very late, very over budget, and often with technical difficulties. Worse, the focus on pleasing corrupt lawmakers like Senator Richard Shelby (R-Alabama) means that NASA is often hostile to the success in manned space by others, such as SpaceX.

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Video from Hayabusa-2’s touchdown

7:51 am

The Hayabusa-2 science team has released a video taken of the spacecraft’s quick touchdown and sample grab on the asteroid Ryugu.

I have embedded the video below the fold. It not only shows the incredible rockiness of Ryugu’s surface, with the spacecraft barely missing a large rock as it came down, it also clearly shows the resulting debris cloud and surface changes after touchdown and the firing of Hayabusa-2’s projectile into the surface to throw up material that the spacecdraft could catch. You can actually see pebbles flying about below and around the spacecraft as it quickly retreats.

The Hayabusa-2 science team plans another touchdown in the next few months, this time using a different technique to disturb the surface and grab the resulting ejecta.
» Read more

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Beresheet sends back first pictures

7:35 am

The privately-built Israeli lunar lander Beresheet has sent back its first pictures, taken on its way to the moon.

The picture, taken 37,600 km from Earth, shows the Israeli flag and the inscription with “Am Yisrael Hai” (the People of Israel Live) in Hebrew and the inscription “Small Country, Big Dreams” in English. The spacecraft was snapped as it passed over Australia, and the photograph was taken during a very slow rotation by Beresheet. The Israeli spacecraft, built in an IAI factory, is in an elliptical orbit around Earth – its greatest distance from Earth (the apogee) at this stage is some 131,000 kilometers.

While the press wants to trivialize this image by calling it a selfie, it was taken for very important engineering reasons. It demonstrates that the camera and the spacecraft’s pointing systems are working, exactly as planned.

Beresheet will continue to raise the apogee of its orbit until it enters the Moon’s gravitational sphere of influence, when it will then shift into lunar orbit.

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Hubble’s main camera down

1:36 pm

The main camera on the Hubble Space Telescope has suspended operations, and remains so as engineers troubleshoot the problem.

According to NASA, at 8:31 p.m. EST Feb. 28 (01:31 GMT March 1), 2019, the Advanced Camera for Surveys, or ACS, suspended its operations when an error was detected while the instrument was performing a routine boot procedure. “The error indicated that software inside the camera had not loaded correctly,” a statement from NASA reads. “A team of instrument system engineers, flight software experts and flight operations personnel quickly organized to download and analyze instrument diagnostic information.

They have not yet pinpointed the cause of the problem. The telescope has other cameras, however, though one of which had problems several months ago.

It is ten years since the last shuttle repair mission. That mission was expected to extend the telescope’s life for five years. Thus, the end Hubble’s life is getting closer and closer.

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Scientists confirm first exoplanet candidate found by Kepler

1:07 pm

Worlds without end: Ten years after Kepler was launched into space to find exoplanets, astronomers have finally confirmed one of the space telescopes thousands of candidates.

Despite being the very first planet candidate discovered by NASA’s Kepler Space Telescope, the object now known as Kepler-1658 b had a rocky road to confirmation. The initial estimate of the size of the planet’s host star was incorrect, so the sizes of both the star and Kepler-1658 b were vastly underestimated. It was later set aside as a false positive when the numbers didn’t quite make sense for the effects seen on its star for a body of that size. Fortuitously, Chontos’ first year graduate research project, which focused on re-analyzing Kepler host stars, happened at just the right time.

“Our new analysis, which uses stellar sound waves observed in the Kepler data to characterize the host star, demonstrated that the star is in fact three times larger than previously thought. This in turn means that the planet is three times larger, revealing that Kepler-1658 b is actually a hot Jupiter-like planet,” said Chontos. With this refined analysis, everything pointed to the object truly being a planet, but confirmation from new observations was still needed.

“We alerted Dave Latham (a senior astronomer at the Smithsonian Astrophysical Observatory, and co-author on the paper) and his team collected the necessary spectroscopic data to unambiguously show that Kepler-1658 b is a planet,” said Dan Huber, co-author and astronomer at the University of Hawaiʻi. “As one of the pioneers of exoplanet science and a key figure behind the Kepler mission, it was particularly fitting to have Dave be part of this confirmation.”

It is important to remember that until scientists obtain independent data on each of these candidates, they are not yet confirmed as exoplanets, and might only be false positives. To do this, however, is going to take a lot of work and time.

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Sunspot update February 2019: The Sun flatlines again

1:26 pm

We are now deep into solar minimum. On Sunday NOAA released its the monthly update of the solar cycle, covering sunspot activity for February 2019. As I have done every month since the start of Behind the Black, I am posting it below, annotated to give it some context.

February 2019 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

For the second time since the beginning of the solar minimum last year, the Sun flat-lined for an month, producing no visible sunspots during the entire month of February.

That streak has continued into March. At present we are four days into March, and still no sunspots.

The big question that I will be repeating probably every month for the next two years is whether we are merely experiencing an early and possibly deep solar minimum, or the advent of a new grand minimum, with no visible sunspots for decades. During the last grand minimum in the 1600s there is evidence the Earth cooled, so much so that it was labeled the Little Ice Age. And with previous grand minimums over the past few thousand years there is evidence that similar coolings occurred. Similarly, periods where sunspot activity was high also appear to have been periods of warmer temperatures.

Why is not clearly understood, though there is some evidence that it might be related to the increasd cosmic ray flux during solar minimum.Those rays might interact with the atmosphere to produce more clouds, thus cooling the Earth. This is not proven however and remains merely a theory linked to some tentative preliminary evidence.

If we do enter a grand minimum, scientists will likely get the answers to these questions. However, we might also find ourselves experiencing significantly colder weather. I am right now flying from Chicago to Columbus, over Lake Michigan, which is filled with ice floes, something we have not seen in March for decades. Nor has this kind of cold weather been unusual for the past decade or so. Could it be because of the weak solar maximum we just experienced and the deep and extended solar minimum just before that? No one knows.

All we can do is gather data, and find out.

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Ceres has too much water!

11:29 am

The uncertainty of science: In a paper released today, scientists puzzle over the amount of water they have detected evaporating from the dwarf planet Ceres, finding that observations by Dawn of its surface do not provide enough water sources to explain the amount of water in its thin atmosphere.

From the abstract:

The dwarf planet Ceres, the largest object in the asteroid belt, is known to contain large amounts of water ice, and water vapor was detected around it. Possible sources of the water are surface exposure of ice through impacts and subsequent sublimation when heated by sunlight, or volcanic activity. It turns out that with either process it is difficult to create sufficient water vapor to explain the observations. This means that the geological processes on Ceres are not fully understood.

They propose several possible explanations for the discrepancy. Either the measurements of evaporation are wrong, or they have not fully mapped the surface water sources on Ceres. Either or both are certainly possible, as there are great uncertainties here.

To me, the most interesting quote from their paper however is the amount of water discovered. Besides finding water on the surface at nine locations “localized on crater floors or slopes, and generally in or close to shadows,” they also found a lot of water under the surface.

The gamma ray and neutron detector on Dawn discovered a global ice‐rich layer in the subsurface of Ceres, at a depth of ~1 m in equatorial regions and much closer to the surface in polar regions. The estimated abundance of ice in this layer is ~10%. … Evidence for ice on depth scales of a few kilometers is [also] reported by Sizemore et al. (2018). From the analysis of geomorphological features, they find that the distribution of ice is heterogeneous on scales of 1 km to hundreds of kilometers.

In other words, Ceres has a lot of water below the surface, even if the evaporation rate observed by Dawn does not at present match the amount of water vapor observed surrounding Ceres.

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Curiosity sends its first images in two weeks

9:30 am

The computer problems that caused Curiosity to cease science operations two weeks ago appears to have ended with the arrival of the first new images today.

The second link above goes to the images arriving today from Curiosity’s ChemCam camera, designed to take macro images of small features on the surface. The rover also sent down a small set of thumbnail images taken by one of its navigation cameras.

It appears they have figured out why the computer did an unexpected reboot in mid-February, and are now willing to let the rover resume science operations. There is no word on what they have learned, or whether it poses a future threat to the mission, but the fact that they are downloading new data is a good sign.

I must note again that this is news you will not see anywhere else. Most news sources today will wait for the NASA press release to report on Curiosity’s recovery, while I like to do some real journalism, reporting events as they happen. Consider this another reason to donate to Behind the Black during this month’s fund-raising drive.

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Planet-wide groundwater system on Mars

9:15 am

Old news: The European Space Agency today released a press release announcing the results of a science paper that appears to have found evidence of a planet-wide groundwater system on Mars.

I call this old news because I reported on this paper a month ago here on Behind the Black: Well water likely available across Mars.

We are now near the end of my February birthday-month fund-raising drive. If anything should justify a donation or subscription, this story should provide it. You can either wait for the mainstream press to rewrite press releases, or you can support my effort to get real news to you now, reported with both enthusiasm and honest skepticism.

I really do hate to brag, but I also don’t believe in false modesty.

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ExoMars prototype test driven from 6,000 miles away

8:43 am

The engineering team that will drive ExoMars 2020 on the surface of Mars in 2021 has completed a test drive using an engineering prototype, controlling it from more than 6,000 miles away.

Experts at the European Space Agency’s centre in Oxfordshire completed a series of tests across nearly 6,900 miles (11,000 km) in order to see how the Mars rover reacts to commands across large distances.

When on the surface of Mars, the rover will need to be controlled when it is up to 250 million miles from Earth.

The trials team used a new model called ‘Charlie’ to test hardware, software and to practice science operations for the future European Space Agency (ESA) ExoMars rover, which will look for life on Mars in 2021. The Atacama desert was chosen because it is the closest we can get to a Martian-like environment.

I must admit that every press release from Europe about ExoMars 2020 gives me worried chills. Each release is often filled too much with empty boasts and little substantive detail. Worse, each seems to repeatedly remind me of some guy working in his garage on a weekend project.

The issue could merely be a case of poor press release writing, but something about each release makes these alarm bells go off in the back of my mind. With the launch only about sixteen months away, I hope I am wrong.

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Waterlike Martian lava flows

2:03 pm

Flowing like water
Click for full image.

Each month the Mars Reconnaissance Orbiter (MRO) science team highlights with captions about four out of the 300-500 new images released that month.

Of the four captioned images in February, the first was entitled “Almost Like Water,” and focused on the waterlike nature of the lava flow. The image on the right is a cropped and annotated section of that featured photograph, with the yellow arrows indicating the flow directions.

The lava appears to have flowed smoothly around obstructions, almost like water, forming streamlined islands. In the southern part of this image, a branch of the flow diverts around a small crater, and eventually rejoins the main part of the flow. [Visible in the full photograph] Irregular-shaped ring structures appear on the northern end and are related to the volcanic activity that formed the flows.

You can see an example of one of those islands near the top of the above image.

This is hardly the only MRO image showing such flows. In fact, the February image release included a bunch, some of the more intriguing of which I highlight below. These lava flows are seen in many different places on Mars, in a wide variety of geological settings, facts that suggest that volcanic activity was once very widespread and ubiquitous on Mars.
» Read more

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No laser communications system at Tabby’s Star

10:32 am

If alien megastructures exist at Tabby’s Star, new research has precluded the likelihood that those aliens are using lasers for communications within those gigantic structures.

[The scientists checked] for laser signatures, on the not unreasonable grounds that any structure large enough to encase a star – Boyajian [Tabby’s Star] is almost one-and-a-half times the mass of the sun – would have an internal communication system, for which lasers would represent a good candidate medium.

In the latest research, Lipman and colleagues decided to test the idea. They analysed 177 high-resolution spectra from the star, gathered by the Lick Observatory’s Automated Planet Finder telescope as part of the Breakthrough Listen Project. They estimated that the data was so detailed that lasers with power greater than 24 megawatts should show up. To hunt for them, the researchers developed an algorithm to perform a pixel-by-pixel analysis of each spectrum in order to identify “spatially unresolved emission lines that meet the criteria for an artificial laser signal”.

The good news is that they found several. The bad news is that a secondary multi-step analysis designed to pick up false positives discounted them all. “The top candidates from the analysis can all be explained as either cosmic ray hits, stellar emission lines or atmospheric air glow emission lines,” they conclude.

We must remember that alien megastructures are the most unlikely explanation for the random light fluctuations of Tabby’s Star. This research helps to strengthen that conclusion.

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Bad climate science, bad climate journalism

1:17 pm

The coming dark age: It appears that the most fundamental concept of science, that all research is subject to skepticism, questioning, and doubt, is no longer followed by the world’s leading science journal Science, in either the research or journalism it publishes.

In reporting today how the Trump administration is establishing a climate review panel that will include global warming skeptics, this so-called science journal describes this effort as follows:

The White House is recruiting researchers who reject the scientific consensus on climate change for its “adversarial” review of the issue.

The proposal to form a “Presidential Committee on Climate Security” at the National Security Council (NSC) has shifted, into an ad-hoc group that will review climate science out of the public eye. Those involved in the preliminary discussions said it is focused on recruiting academics to conduct a review of the science that shows climate change presents a national security risk.

William Happer, a senior director at the NSC and an emeritus Princeton University physics professor not trained in climate science, is leading the effort.

Among those who have been contacted are the relatively small number of researchers with legitimate academic credentials who question the notion that humans are warming the planet at a rapid pace through the burning of fossil fuels. A number of the names the White House is targeting are those frequently invited by Republicans to testify at congressional hearings on climate change where uncertainty is emphasized.

The stated goal of the committee, according to a leaked White House memo, is to conduct “adversarial scientific peer review” of climate science. [emphasis mine]

The article also stated that the panel “will also include scientists who agree with the vast majority in the field of climate science that humans are warming the planet at a pace unprecedented in the history of civilization.”

First of all, it is not clear that “a vast majority in the field of climate science” agree with that global warming hypothesis. And even if it was, it would not matter. Science isn’t determined by consensus or majority rule. It is determined by facts, and if the facts don’t support the beliefs of 97% of all climate scientists, all 97% of those scientists are wrong. That this writer and the editors at Science don’t understand this is shocking.
» Read more

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Hayabusa-2 touchdown images released

8:28 am

Surface of Ryugu 1 minute after touchdown

The Hayabusa-2 science team today released images taken during its quick touchdown on the asteroid Ryugu last week.

The image to the right was taken:

roughly 1 minute after touchdown at an estimated altitude of about 25m (error is a few meter) [80 feet]. The color of the region beneath the spacecraft’s shadow differs from the surroundings and has been discolored by the touchdown. At the moment, the reason for the discoloration is unknown but it may be due to the grit that was blown upwards by the spacecraft thrusters or bullet (projectile).

The image proves that everything on Hayabusa-2 worked as planned, and it almost certainly captured some of that grit.

They are going to do at least two more touchdowns before they have Hayabusa-2 leave Ryugu and head back to Earth.

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Most popular theorized particle for explaining dark matter now eliminated

11:54 am

The uncertainty of science: The WIMP particle (Weakly Interacting Massive Particle), the most popular theorized particle to explain dark matter, has now been eliminated by experiments.

These experiments have now been ongoing for decades, and have seen no dark matter [WIMPs].

…Theorists can always tweak their models, and have done so many times, pushing the anticipated cross-section down and down as null result after null result rolls in. That’s the worst kind of science you can do, however: simply shifting the goalposts for no physical reason other than your experimental constraints have become more severe. There is no longer any motivation, other than preferring a conclusion that the data rules out, in doing.

Other theorized but less favored particles could still be proved to be dark matter, but the problem is getting harder and harder to solve, as presently assumed.

Dark matter has always been an invention created to explain the too-fast orbital velocities of stars in the other regions of galaxies. It could very well be however that the problem comes not from new physics and a newly contrived particle we can’t see, but from a deficiency in our overall observations of galaxies and what is there, within the constraints of the physics we know now.

Hat tip Mike Buford.

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New high resolution images of Ultima Thule

5:59 pm

Highest resolution image of Ultima Thule
Click for full resolution image.

The New Horizons team has released new high resolution images of Ultima Thule, taken during its fly-by on January 1, 2019.

These new images of Ultima Thule – obtained by the telephoto Long-Range Reconnaissance Imager (LORRI) just 6½ minutes before New Horizons’ closest approach to the object (officially named 2014 MU69) at 12:33 a.m. EST on Jan. 1 – offer a resolution of about 110 feet (33 meters) per pixel.

…The higher resolution brings out a many surface features that weren’t readily apparent in earlier images. Among them are several bright, enigmatic, roughly circular patches of terrain. In addition, many small, dark pits near the terminator (the boundary between the sunlit and dark sides of the body) are better resolved. “Whether these features are craters produced by impactors, sublimation pits, collapse pits, or something entirely different, is being debated in our science team,” said John Spencer, deputy project scientist from SwRI.

Available at the link above is a three-second long movie they created from these images, showing Ultima Thule as it zips across the camera’s view.

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Another batch of caves/pits found on Mars

1:10 pm

Four new pits on Mars

Overview of February 2019 pits

In the past year the monthly image releases from the high resolution camera on Mars Reconnaissance Orbiter (MRO) archive have frequently included newly discovered pit entrances. Each time I have written posts highlighting these new pits, in June, July, November 2018 and January 2019. In fact, this is happening so frequently I could almost label it a monthly update!

The November release imaged three pits found on the southern flanks of Arsia Mons. The January 2019 release found several north of the volcano, two of which are very close to the two middle new pits highlighted above. The February release, which is the focus of this post, included four more pits, shown above, all located north and west of Arsia Mons, as shown in the overview map to the right.

Pits 2 and 3 above appear to belong to a cluster of pits all located in the general area between Arsia and Pavonis Mons. (You can see their uncaptioned releases here and here.) Most sit alone on a flat somewhat featureless plain. Sometimes there are flow features nearby, but each pit usually seems to sit unique and unrelated to these other faint features.

Pit 1 is very intriguing in that it sits amid a very long chain of pits and canyons, all aligned, as shown in the image below and to the right.
» Read more

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Astronomer discovers newest farthest solar system object

8:16 am

Worlds without end: An astronomer leading a team looking for a large planet beyond Pluto has broken their own record and found a new solar system object that is the farthest known from the Sun.

That’s when he saw it, a faint object at a distance 140 times farther from the sun than Earth — the farthest solar system object yet known, some 3.5 times more distant than Pluto. The object, if confirmed, would break his team’s own discovery, announced in December, of a dwarf planet 120 times farther out than Earth, which they nicknamed “Farout.” For now, they are jokingly calling the new object “FarFarOut”. “This is hot off the presses,” he said during his rescheduled talk on 21 February.

I like the names for both.

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Confirmed: Hayabusa-2 grabbed got a sample of Ryugu

9:22 pm

The Hayabusa-2 science team has confirmed that in the spacecraft’s quick touchdown on the surface of the asteroid Ryugu today it successfully snagged an asteroid sample.

Mission team members announced at about 6:30 p.m. EST (2330 GMT) today that the order to fire the bullet had been issued, and that Hayabusa2 had moved away from Ryugu as planned. But it took a few more hours for them to confirm that the bullet had indeed fired, and that sample collection occurred.

…The collected samples are key to this objective: The Ryugu material will come down to Earth in a special return capsule in December 2020. Scientists in labs around the world can then scrutinize the stuff with far more advanced equipment than the Hayabusa2 team could pack onto a single spacecraft.

The sample bounty will include more than just the material Hayabusa2 collected today. The mothership is expected to grab two more samples in the coming weeks and months. The second sampling sortie will unfold much like today’s did, but the third will be dramatically different: Hayabusa2 will fire a copper projectile into Ryugu, wait a bit for the dust to clear, and then swoop in to grab material from the newly created crater. This formerly subsurface stuff will be pristine, unaffected by weathering from deep-space radiation.

More thrills to come, obviously.

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NASA selects experiments it wants to put on commercial lunar spacecraft

4:51 pm

Capitalism in space: NASA has selected a dozen experiments/instruments it wants to put on private commercial lunar spacecraft, either landers or rovers.

According to the press release, some of these could fly as early as before the end of this year. If so, I suspect they will go on one of the finalists for the Google Lunar X-prize, some of whom are planning to fly this year.

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Hayabusa-2 has begun approach to Ryugu

8:37 am

Ryugu during approach

Hayabusa-2 has begun its approach to Ryugu, aiming for a quick touchdown and sample grab at approximately 7:06 pm (Eastern) tonight. The image at the right is the most recent taken during the approach.

The risks? From the Hayabusa-2 website:

Our original schedule planned for touchdown in late October of last year (2018). However, Ryugu was revealed as a boulder strewn landscape that extended across the entire surface, with no flat or wide-open regions. Before arriving at Ryugu, it was assumed there would be flat areas around 100 meters in size. But far than finding this, we have not even seen flat planes 30 meters across!

During the scheduled time for touchdown in late October, we did not touchdown but descended and dropped a target marker near the intended landing site. We were able to drop the target marker in almost the planned spot and afterwards we examined the vicinity of the target marker landing site in detail. Finally, the area denoted L08-E1 was selected as the place for touchdown.

From the first link above you can see approach images as they are downloaded today, about once every half hour.

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Hayabusa-2 prepares to land

9:54 am

Ryugu's northen hemisphere

The JAXA science team has released a set of images taken in January by Hayabusa-2 of its landing site on Ryugu, describing how those images helped map the region where touchdown will occur on February 22. The image on the right is one such image.

[It] shows a diagonally imaged photograph of Ryugu, captured by moving the spacecraft towards the direction of the north pole. The upper side of the image shows the north pole and reveals a landscape dominated with many large boulders. The white band extending to the left and right slightly below the center of the image is the equatorial ridge (Ryujin Ridge). The arrow tip marks the planned touchdown site and you can see this site is on the main ridge.

This is the first time we have images the northern hemisphere of Ryugu. In this observation, we acquired data on the equatorial region of Ryugu, the southern and northern hemisphere. Imaging the entire area is very important for creating accurate global shape models for Ryugu.

They should begin beaming images down of the landing approach sometime tomorrow, and will do so about every 30 minutes throughout the sequence.

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New sky survey uncovers hundreds of thousands of previously unknown galaxies

11:02 am

Galaxies without end: A new radio telescope sky survey has discovered hundreds of thousands of previously unknown galaxies.

This discovery is part of a major release of papers outlining a number of discoveries made by this new sky survey.

I could of course also subheaded this post “The uncertainty of science.” Wanna bet that even with this discovery we have only seen the tip of the iceberg of the number of galaxies out there?

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A very old white dwarf star with rings?

10:19 am

The uncertainty of science: A citizen scientist has discovered a very old white dwarf star that apparently has one or more dust rings it should not have.

The star, LSPM J0207+3331 or J0207 for short, is forcing researchers to reconsider models of planetary systems and could help us learn about the distant future of our solar system. “This white dwarf is so old that whatever process is feeding material into its rings must operate on billion-year timescales,” said John Debes, an astronomer at the Space Telescope Science Institute in Baltimore. “Most of the models scientists have created to explain rings around white dwarfs only work well up to around 100 million years, so this star is really challenging our assumptions of how planetary systems evolve.”

In other words, we don’t really yet understand the processes that form solar systems or even stars. This isn’t because we can’t figure this out, but because we don’t yet have enough information on hand. What we do know tells us that stars and solar systems both form from accretion disks. The information also gives us a general idea of the pattern of formation, but not much more.

For example, one question I have asked a number of astronomers is: Why are some stars gigantic monsters and others dwarfs? Based on present theories of stellar evolution, it seems to me that all stars should be the same size, as accretion is thought to end when the star reaches a heavy enough mass to ignite its nuclear engine. Yet this is not what we find. Why? I’ve never gotten a good answer.

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