Tag: science

Dawn finds organics on Ceres

9:34 pm

The spacecraft Dawn has detected evidence of organic molecules in Ceres’ northern hemisphere.

The organic materials on Ceres are mainly located in an area covering approximately 400 square miles (about 1,000 square kilometers). The signature of organics is very clear on the floor of Ernutet Crater, on its southern rim and in an area just outside the crater to the southwest. Another large area with well-defined signatures is found across the northwest part of the crater rim and ejecta. There are other smaller organic-rich areas several miles (kilometers) west and east of the crater. Organics also were found in a very small area in Inamahari Crater, about 250 miles (400 kilometers) away from Ernutet.

This detection does not mean that Dawn has found life on Ceres. It means that the spacecraft has detected molecules that contain carbon, which is the chemical definition of organics. Nor is it unusual for asteroids to have carbon molecules. In fact, there is an entire asteroid class dubbed carbonaceous chondrites that are rich in carbon. In addition, the press release overplays this narrative by making it seem as if the discovery of organics in the solar system is rare and unusual. It is not. Molecules containing carbon have been found in many places, on Mars, on Venus, in asteroids, and elsewhere. All that is happened here is that the scientists have gained more information about the make-up Ceres itself. This is good, but it isn’t what is being sold by the press release.

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UAE proposes building Martian city within a century

12:13 pm

The competition heats up? The United Arab Emirates announced on Tuesday its plan to construct a city on Mars and have it completed by 2117, a hundred years from now.

On Tuesday, at the sidelines of the World Government Summit in Dubai, the UAE announced that it was planning to build the first city on Mars by 2117. According to CNBC, UAE engineers presented a concept city at the event about the size of Chicago for guests to explore.

In a statement, Sheikh Mohammed bin Rashid Al Maktoum, ruler of Dubai and vice president of the UAE, sounded confident about the project. “Human ambitions have no limits, and whoever looks into the scientific breakthroughs in the current century believes that human abilities can realize the most important human dream,” Maktoum said.

And despite the grandiose nature of the idea, the 100-year-plan does emphasize some practical steps. “The Mars 2117 Project is a long-term project,” Maktoum explained in the statement, adding that the first order of business would be making space travel appeal to young Emiratis, with special programs in space sciences being set up at universities in the UAE.

Maktoum is the guy that pushed to create the UAE’s space agency, and is leading its effort to fly an unmanned mission to Mars by 2020. It is very clear that his goal is to inspire his country and its youth so that they will aim high in future years. I wish him well, as this is a far better goal for an Islamic nation than sending out suicide bombers to kill innocent people.

I must add that I remain very skeptical about this particular plan. I fully expect us to finally get to Mars in the next century, but whether we will have the ability to build cities there in that time frame remains questionable.

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Maybe the Earth’s magnetic field is not weakening

3:31 pm

The uncertainty of science: New data using date-stamped jars covering the period from the 8th to the 2nd century BC suggest that the 8th century BC was a period when the Earth’s magnetic field was particularly strong, leading the scientists doing the research to conclude that the Earth’s magnetic field might not be weakening and that the recent field strength decline detected in the past two hundred years might simply be part of the field’s normal fluctuations.

This new data is certainly worthwhile, but the press release surely doesn’t reveal how the scientists were able to extrapolate future magnetic field strength from 8th century BC fluctuations. At a minimum, I would need to see a graph showing the measured field strength from the 8th century BC to the present time to see how today’s field strength compares with the past. Unfortunately, the press release does not provide this.

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Mars rover update: February 14, 2017

2:54 pm

Curiosity

Ireson Hill, Sol 1604

Dune fields

For the overall context of Curiosity’s travels, see Pinpointing Curiosity’s location in Gale Crater.

Taking a close look at rock

Since my last update in January, Curiosity done more or less what I predicted. It headed southwest through the dune area and then made a side trip to the small mesa there, dubbed Ireson Hill by the Curiosity science team and shown on the right. They then made an additional side trip past the hill to get a close look a the large sandy dune field beyond, also shown on the right. After getting some nice closeups as well as scooping up some sand for observation, they have now gone back to Ireson Hill to get another close look at the dark rocks that have rolled off the top of the hill and are now in reach at its base. The image on the left shows the arm positioned above one of those rocks.

The drill remains out of commission, with no word when they will try using it again. In addition, there had been a problem with the ChemCam laser that does spectroscopic analysis, but as of this week it is back in action, and is being used to analysis the small rock above.

Below is an overview of their route so far as well as my annotations on where I think they will be heading in the future.
» Read more

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A comet breaks apart

9:27 am

On February 12 members of the amateur astronomy organization Slooh actually viewed the break-up of Comet 73P/Schwassmann-Wachmann into two large fragments.

On the night of February 12th, Slooh members using the company’s telescopes in Chile were able to view the comet as it broke into two pieces. This seems to be the continuation of a process that was first witnessed in 1995, then again in 2006.

Slooh members were among the first to confirm that the nucleus of comet 73P/Schwassmann-Wachmann had split into at least two large pieces. “They immediately pointed Slooh’s telescopes to capture the event,” says Slooh Astronomer, Paul Cox. “Members will continue to monitor the comet live over the coming weeks – assuming the comet survives that long.”

They have created an animation from their images, but it appears that they only started taking images after the actual breakup, so the animation shows the two fragments, but not the moment they broke apart.

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Heart risks from secondhand smoke completely bogus

7:09 pm

The uncertainty of science: New more carefully done research now proves that secondhand smoke from smoking does almost nothing to increase the risk of heart disease.

In the early 2000s, as jurisdictions across the country fought over expanding smoking bans to bars and restaurants, anti-smoking advocates seized on the Helena study and related research showing that secondhand smoke exposure can affect coronary functions to promote fear of secondhand smoke. Groups across the country stated that “even half an hour of secondhand smoke exposure causes heart damage similar to that of habitual smokers.” Not to be outdone, the Association for Nonsmokers in Minnesota wrote in a press release that just 30 seconds of exposure could “make coronary artery function of non-smokers indistinguishable from smokers.” The message to nonsmokers was clear: The briefest exposure to secondhand smoke can kill you.

A decade later, comprehensive smoking bans have proliferated globally. And now that the evidence has had time to accumulate, it’s also become clear that the extravagant promises made by anti-smoking groups—that implementing bans would bring about extraordinary improvements in cardiac health—never materialized. Newer, better studies with much larger sample sizes have found little to no correlation between smoking bans and short-term incidence of heart attacks, and certainly nothing remotely close to the 60 percent reduction that was claimed in Helena. The updated science debunks the alarmist fantasies that were used to sell smoking bans to the public, allowing for a more sober analysis suggesting that current restrictions on smoking are extreme from a risk-reduction standpoint.

As almost always happens, the people pushing for the ban really weren’t that interested in protecting people’s health. They might have thought so, but in reality what they were really interested in was exerting their power over others, banning smoking and telling everyone else how to live their lives.

Read the whole article. It is very damning, and illustrates again why it is very important to not pass laws quickly based on some preliminary scientific results. Care must be taken, and patience is required. The science is never clear right from the beginning, especially on complex issues like climate and the health effects involving large numbers of people.

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NSF voids punishment of scientists who committed plagiarism and data fabrication

10:34 am

An inspector general report has found that the National Science Foundation has routinely cancelled or reduced the punishments of scientists who had committed either plagiarism or data fabrication, allowing them to continue to get grants and advise the government.

The inspector general for the National Science Foundation identified at least 23 instances of plagiarism in proposals, NSF-funded research, and agency publications in 2015 and 2016. It found at least eight instances of data manipulation and fabrication in those years. NSF officials disregarded recommended sanctions against some of the scientists and academics implicated in those findings. Though many were temporarily barred from receiving additional federal funding, nearly all will be eligible for taxpayer support and official roles in NSF-funded research in the future.

In one investigation that concluded in Nov. 2015, the IG found that an NSF-supported researcher had “knowingly plagiarized text into five NSF proposals.”

“These actions were a significant departure from the standards of the research community, and therefore constituted research misconduct,” according to a report on the investigation’s findings.

No wonder the public has become very skeptical of government science. Worse, by turning a blind eye to this bad behavior the National Science Foundation ends up giving a black eye to all science.

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NASA narrows to three the Mars rover landing sites in 2020

2:59 pm

Jezero Crater

Scientists have now narrowed to three the candidate landing sites for NASA’s 2020 Mars rover mission.

The three sites include Jezero crater, which was once home to an ancient Martian lake and which could preserve the remains of microbial life, if it ever existed on Mars. “You’ve got a large river bringing water and sediment into a very large lake, comparable to Lake Tahoe,” says Timothy Goudge, a planetary scientist at the University of Texas at Austin. Jezero scored highest on a community vote of scientists attending the workshop.

Other possible targets include Northeast Syrtis, where hot waters once circulated through the crust and could have supported life, and Columbia Hills, the area explored for years by NASA’s Spirit rover.

From the Nature article above as well as this Science article, it sounds like the Columbia Hills choice is unlikely. The Science article pushes Jezero crater, which had the most votes at the workshop and is shown in the image on the right.

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How Differential Gear works

6:02 pm

An evening pause: Though the first 1:50 of this very well done 1930s industrial is somewhat irrelevant and can be skipped, I think it is worth watching anyway. And the rest does a great job of explaining this mysterious piece of automobile equipment.

Hat tip Edward Thelen.

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An orbital change extends the life of India’s Mars orbiter

8:32 am

An orbital maneuver has allowed India’s Mars Orbiter Mission avoid an eight hour period with no sunlight — thus draining its batteries — so that the mission can be extended until 2020.

The on-board battery which was to take over had a life of just about 1.4 hours, while the eclipse was to last for 8 hours. The spacecraft’s future was bleak.

The scientists thought of a solution. On the night of January 17, a team of eight engineers at Indian Space Research Organisation’s Telemetry, Tracking and Command Network, Bengaluru, sent a time-delayed command to the Mars probe. The command set in motion firing of eight on-board thruster rockets. Each of them were fired for 431 seconds, pushing the Mars Orbiter Mission (MOM) space probe to a new orbit that completely avoids an eclipse up to September 2017. The shadowing in September is of a smaller duration, which the satellite’s batteries can handle. “Because of the crucial orbital change, the MOM now gets three additional years’ life. We are expecting it to transmit data till 2020,” Isro chairman A S Kiran Kumar told DH.

The mission’s science data is not as important as the experience it is giving Indian engineers in operating a planetary probe remotely from Earth. This success speaks well for the future of India’s space effort.

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New Curiosity data leaves scientists baffled about past evidence of water

2:37 pm

The uncertainty of science: Despite substantial evidence by Curiosity that Gale Crater once had running water and even lakes, the rover has also found no evidence that the atmosphere ever had enough carbon dioxide in its atmosphere to warm the climate enough to allow that water to flow as a liquid.

Mars scientists are wrestling with a problem. Ample evidence says ancient Mars was sometimes wet, with water flowing and pooling on the planet’s surface. Yet, the ancient sun was about one-third less warm and climate modelers struggle to produce scenarios that get the surface of Mars warm enough for keeping water unfrozen.

A leading theory is to have a thicker carbon-dioxide atmosphere forming a greenhouse-gas blanket, helping to warm the surface of ancient Mars. However, according to a new analysis of data from NASA’s Mars rover Curiosity, Mars had far too little carbon dioxide about 3.5 billion years ago to provide enough greenhouse-effect warming to thaw water ice.

The same Martian bedrock in which Curiosity found sediments from an ancient lake where microbes could have thrived is the source of the evidence adding to the quandary about how such a lake could have existed. Curiosity detected no carbonate minerals in the samples of the bedrock it analyzed. The new analysis concludes that the dearth of carbonates in that bedrock means Mars’ atmosphere when the lake existed — about 3.5 billion years ago — could not have held much carbon dioxide.

Does anyone but me see the faulty scientific reasoning here? Basically, these scientists appear to be assuming that the only global warming atmospheric molecule that exists is carbon dioxide. And because Mars has little carbonates in its surface, meaning it had little past CO2 in its atmosphere, there thus no way Mars’ atmosphere could have been warmed enough to allow water to flow as a liquid.

Balderdash! On Earth, the most important global warming component in the atmosphere is water, not carbon dioxide. Moreover, there are other atmospheric components, such as methane, that are also more important than CO2 in warming the climate. In fact, carbon dioxide as a trace gas in the atmosphere plays only a tiny global warming role. On Mars it is just as likely that other atmospheric components, such as water and methane, provided the necessary warming. To assume it has to be carbon dioxide suggests to me that these scientists have become so caught up with the human-caused global warming scare here on Earth that they have lost the ability to consider other possibilities on Mars.

Nonetheless, this remains the fundamental scientific mystery of Mars. We have found enormous evidence on Mars that water once flowed on its surface. We have also found no explanation so far that would explain how that was possible.

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The Sun turns

11:33 am

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for January. As I do every month, I am posting it here with annotations to give it context.

January 2017 Solar Cycle graph

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.

Since my last solar cycle update, sunspot activity showed a slight increase in activity when compared to the previous month. Overall, however, the ramp down from solar maximum continues to underperform the predictions, and suggests that this solar maximum will not only be a very weak one, but a short one as well.

January’s activity however illustrated a statistical phenomenon that is typical of the sunspot count. That count is determined not by the numbers of sunspots on the entire surface of the Sun, but on the sunspots visible on the side of the Sun facing the Earth. Since it is not unusual for one face to be more active than the other, as we transition from maximum to minimum the sunspot counts will often show a more pronounced up-and-down curve reflecting this fact. Since the Sun’s day equals about 27 Earth days, this means that about every two weeks the active side will dominate our view until it rotates away and the inactive side reveals itself for two weeks.

Silso daily sunspot graph, January to February 2017

This pattern was very evident in January, as shown by the graph on the right and obtained from here. During the first two weeks of the month the Sun was blank. Then that inactive face rotated out of view. For the next two weeks or so the sunspot count went up, then began to drop as the active face began to rotate out of view to be replaced by the blank face last seen in early January.

This pattern of course is very fluid, as at any time the inactive face can become more active and the active face less so. Nonetheless, for short periods covering one to three months it helps to partly explain the up-and-down pattern of sunspot fluctuations during this time period when large portions of the Sun’s face are blank.

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At Jupiter reality imitates art

9:20 am

Jupiter's south pole, fourth flyby

NASA this week released images taken by Juno during its fourth close fly-by of Jupiter on February 2. The image highlighted by that press release focused on a wide lightly processed view of the south pole, different from the image above. As the release states,

Prior to the Feb. 2 flyby, the public was invited to vote for their favorite points of interest in the Jovian atmosphere for JunoCam to image. The point of interest captured here was titled “Jovian Antarctica” by a member of the public, in reference to Earth’s Antarctica.

The image above, cropped and reduced here, was more heavily processed by another member of the public, and shows more clearly the mad, chaotic storms at the south pole.

What instantly struck me when I saw this however was how much it reminded me of this piece of art, painted in 1889 in France by a man who was slowly going insane.

The Starry Night

Vincent Van Gogh never saw the storms on Jupiter, but his imagination conceived their existence in paint. Juno has now imaged them in reality.

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Whistleblower exposes climate data manipulation at NOAA

12:00 am

The corruption of climate science: A retired award-winning climate scientist has revealed that the publication of a NOAA paper that claimed the pause in global warming since 1998 did not exist was rushed into publication so that it would appear just prior to the Paris climate conference in 2015.

Worse, the paper’s authors disregarded NOAA’s rules for peer review, destroyed their raw data so that no one could check their results, and purposely threw out data that raised questions about their conclusions.

NOAA’s 2015 ‘Pausebuster’ paper was based on two new temperature sets of data – one containing measurements of temperatures at the planet’s surface on land, the other at the surface of the seas. Both datasets were flawed. This newspaper has learnt that NOAA has now decided that the sea dataset will have to be replaced and substantially revised just 18 months after it was issued, because it used unreliable methods which overstated the speed of warming. The revised data will show both lower temperatures and a slower rate in the recent warming trend.

The land temperature dataset used by the study was afflicted by devastating bugs in its software that rendered its findings ‘unstable’. The paper relied on a preliminary, ‘alpha’ version of the data which was never approved or verified. A final, approved version has still not been issued.

None of the data on which the paper was based was properly ‘archived’ – a mandatory requirement meant to ensure that raw data and the software used to process it is accessible to other scientists, so they can verify NOAA results.

Read the whole article. It is remarkably detailed for a modern newspaper story, delving carefully into the kind of details that must be looked at to truly understand the corruption of science that has taken place in government agencies like NOAA and NASA.

Does this story prove that human-caused global warming is not happening? Of course not. What it does show is that there is fraud going on, and that much of the science press releases issued by these agencies cannot be trusted.

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Strange beat-up Martian terrain

9:31 am

Strange terrain

Cool image time! The image above, taken by Mars Reconnaissance Orbiter and cropped to show here, reveals some very strange terrain, pounded by numerous impacts. The full color-enhanced image, which only covers a small area of the much larger strip image, shows a rough surface that on Earth would definitely be labeled “badlands.”

The very tiny cropped section above especially intrigued me because of the pronounced cliff that appears to be the north wall of a crater in which the east, west, and south walls have eroded away. The riverlet-like flows down the cliff-face are also intriguing, as are the cross-crossing features in the crater floor.

Make sure you look at the full images. Quite strange and fascinating. Even though the complete image strip isn’t color enhanced. it is filled with many interesting geological forms. I haven’t yet been able to find the spot shown by the color-enhanced section, but it is there nonetheless. I wonder if any of my readers can locate it.

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The vanishing volcanoes of Ceres

10:02 am

New research based on Dawn data suggests that volcanoes on Ceres flatten and disappear over time.

NASA’s Dawn spacecraft discovered Ceres’s 4-kilometer (2.5-mile) tall Ahuna Mons cryovolcano in 2015. Other icy worlds in our solar system, like Pluto, Europa, Triton, Charon and Titan, may also have cryovolcanoes, but Ahuna Mons is conspicuously alone on Ceres. The dwarf planet, with an orbit between Mars and Jupiter, also lies far closer to the sun than other planetary bodies where cryovolcanoes have been found.

Now, scientists show there may have been cryovolcanoes other than Ahuna Mons on Ceres millions or billions of years ago, but these cryovolcanoes may have flattened out over time and become indistinguishable from the planet’s surface. They report their findings in a new paper accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union. “We think we have a very good case that there have been lots of cryovolcanoes on Ceres but they have deformed,” said Michael Sori of the Lunar and Planetary Laboratory at the University of Arizona in Tucson, and lead author of the new paper.

The cause of the flattening?

Viscous relaxation is the idea that just about any solid will flow, given enough time. For example, a cold block of honey appears to be solid. But if given enough time, the block will flatten out until there is no sign left of the original block structure. On Earth, viscous relaxation is what makes glaciers flow, Sori explained. The process doesn’t affect volcanoes on Earth because they are made of rock, but Ceres’s volcanoes contain ice – making viscous relaxation possible.

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UAE considers initiating its own manned space program

9:37 am

The competition heats up: At a space conference this week in Abu Dhabi, a UAE official said that his country might begin work on a manned space program.

He also said that they plan a follow-up to their Hope Mars mission, which now has a July 2020 launch date.

The UAE’s prime goal right now with their space effort is to promote the development of a new aerospace industry. Thus, I do not expect them to accomplish much in the near future. Even their Mars mission is I think mostly being built and launched by others (India is helping with the spacecraft and Japan is launching it). In the long term, however, this effort is wise, and will eventually produce for them a real industry.

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Juno’s next Jupiter fly-by today

9:29 am

Juno is set to make its fourth close fly-by of Jupiter today, dipping to within 2,670 miles of the gas giants cloud tops.

The Juno science team continues to analyze returns from previous flybys. Revelations include that Jupiter’s magnetic fields and aurora are bigger and more powerful than originally thought and that the belts and zones that give the gas giant’s cloud top its distinctive look extend deep into the planet’s interior. Peer-reviewed papers with more in-depth science results from Juno’s first three flybys are expected to be published within the next few months. Also, JunoCam, the first interplanetary outreach camera, is now being guided with the assistance from the public — people can participate by voting for what features on Jupiter should be imaged during each flyby.

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Curiosity’s drill remains out of commission

9:21 am

Ireson Hill

In a science update on Curiosity’s research in Gale Crater, this Science journal article today gives a good overall update on Curiosity’s technical condition.

Since early December 2016, Curiosity hasn’t been able to drill. The problem, likely a stuck brake on the mechanism for extending the drill bit, is serious. “There is apprehension,” says Ashwin Vasavada, Curiosity’s project scientist at the Jet Propulsion Laboratory in Pasadena, California. But the drill still responds intermittently. “We’re not in a situation where it’s completely dead.”

Still, the clock is ticking for the aging rover, and some outside scientists regret not having used a wet chemistry cup. Rocks have punctured its wheels, and the output of its decaying radioactive power source has dropped by 15%. Jack Mustard, a planetary scientist at Brown University, says he understands the team’s hesitancy. But he wished the “mission had moved more quickly with the wet chemistry experiments,” he says. “I am eager to see what we can learn.”

The wet chemistry cup, designed to look for organic life, is an experiment that requires use of the drill but the science team has held off doing. Now it might be too late.

At the moment Curiosity is approaching [see Sol 1598-1599] the small hill that had been to its southwest in my January 18, 2017 update and shown in the image above. I had thought they might make a side trip there on their way up Mount Sharp, and they have, with their actual route taking them around the backside of the hill.

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Plotting the interstellar path to Proxima Centauri

8:40 am

Scientists have calculated the slingshot route that Breakthrough Starshot’s tiny interstellar spacecraft should take in order to reach Proxima Centauri while also gathering the maximum scientific data while zipping past the binary stars of Alpha Centauri.

The solution is for the probe’s sail to be redeployed upon arrival so that the spacecraft would be optimally decelerated by the incoming radiation from the stars in the Alpha Centauri system. René Heller, an astrophysicist working on preparations for the upcoming Exoplanet mission PLATO, found a congenial spirit in IT specialist Michael Hippke, who set up the computer simulations. The two scientists based their calculations on a space probe weighing less than 100 grams in total, which is mounted to a 100,000-square-metre sail, equivalent to the area of 14 soccer fields. During the approach to Alpha Centauri, the braking force would increase. The stronger the braking force, the more effectively the spacecraft’s speed can be reduced upon arrival. Vice versa, the same physics could be used to accelerate the sail at departure from the solar system, using the sun as a photon cannon.

The tiny spacecraft would first need to approach the star Alpha Centauri A as close as around four million kilometres, corresponding to five stellar radii, at a maximum speed of 13,800 kilometres per second (4.6 per cent of the speed of light). At even higher speeds, the probe would simply overshoot the star.

While most of this is hardly revolutionary, this is still the first time anyone has done the hard math based upon a real mission concept.

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U.S. 2020 Mars rover faces delays

9:26 pm

A new inspector general report has pinpointed a number of issues that could cause a delay in the 2020 launch of the next American Mars rover mission.

The biggest risk to the mission, according to NASA OIG, is the sampling system that will be used to collect and store samples of Martian rock and soil that a future mission will gather for return to Earth. That system, an essential part of the mission, has several key technologies that are less mature than planned at this phase of the mission’s development. “The immaturity of the critical technologies related to the Sampling System is concerning because, according to Mars 2020 Project managers, the Sampling System is the rover’s most complex new development component with delays likely to eat into the Project’s schedule reserve and, in the worst case scenario, could delay launch,” OIG stated.

I find it puzzling that the sampling system is an issue. This rover is essentially based on Curiosity, which has very sophisticated equipment for grabbing and even storing samples for periods of time. I don’t understand why such systems could not be quickly revised for future retrieval.

Nonetheless, there are other problems however.

Two instruments on the Mars 2020 mission have also suffered problems. One, called MOXIE, is designed to test the ability to generate oxygen on Mars, saw its estimated increase by more than 50 percent during its development. NASA has taken steps to reduce some of that cost growth by eliminating development of an engineering model and skipping further design improvements in one element of MOXIE.

Another instrument designed to study atmospheric conditions on Mars, MEDA, has suffered delays because of a “financial reorganization” by its developer, Spain’s National Institute for Aerospace Technology. OIG concluded in its report that MEDA is unlikely to be ready for delivery to NASA in April 2018, as currently scheduled. That could require adding MEDA to the rover later in the overall assembly process, or flying the mission without the instrument.

One of the reasons the Obama administration decided to make this 2020 rover mission a reboot of Curiosity was to save cost and development time. Thus, it does not speak well for NASA’s planetary program that they are having these problems.

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Some radioisotope dating might be overestimating the age of samples

7:11 pm

The uncertainty of science: New research suggests the radioisotope dating that scientists use has been overestimating the age of many samples.

The article does not indicate if this overestimate applies to all radioisotope dating or just to the strontium-86/rubidium-87 dating methods mentioned. Nor does the article detail how much of an overestimate the scientists have measured. Depending on these factors the difference — and its influence on scientific results — could be relatively small, or quite large.

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New close-ups of Saturn’s rings

1:00 pm

New close-ups of Saturn’s rings, taken during one of Cassini’s recent ring-grazing orbits, have now been released.

They have released four different images, all at a higher resolution than any previous image. Even so, the individual particles in the rings remain unresolved. Instead, many different intriguing patterns are observed, once again suggesting that though the rings are made of many solid particles, they behave as a unit more like a liquid.

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New measurements of the universe’s expansion rate

3:41 pm

The uncertainty of science: New measurements of the universe’s expansion rate are apparently in agreement with some previous measurements but not with others.

The Hubble constant — the rate at which the Universe is expanding — is one of the fundamental quantities describing our Universe. A group of astronomers, the H0LiCOW collaboration, used the NASA/ESA Hubble Space Telescope and other telescopes in space and on the ground to observe five galaxies in order to arrive at an independent measurement of the Hubble constant. The new measurement is completely independent of — but in excellent agreement with — other measurements of the Hubble constant in the local Universe that used Cepheid variable stars and supernovae as points of reference.

…However, the value measured by Suyu and her team, as well as those measured using Cepheids and supernovae, are different from the measurement made by the ESA Planck satellite. But there is an important distinction — Planck measured the Hubble constant for the early Universe by observing the cosmic microwave background. While the value for the Hubble constant determined by Planck fits with our current understanding of the cosmos, the values obtained by the different groups of astronomers for the local Universe are in disagreement with our accepted theoretical model of the Universe.

Both measurements are very precise, but they do not match, suggesting that there are some basic fundamentals here that astronomers simply do not yet understand.

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Jupiter’s Little Red Spot

9:24 am

Little Red Spot

Cool image time! The image on the right, cropped to show here, is focused in on Jupiter’s Little Red Spot, a storm that formed by the merger of three smaller storms about a decade ago. The cropped image comes from a wider view of Jupiter from Juno that is quite amazing.

Note that the Little Red Spot, while only a third the size the more well known Giant Red Spot, is still about the size of the Earth.

This storm is the third largest anticyclonic reddish oval on the planet, which Earth-based observers have tracked for the last 23 years. An anticyclone is a weather phenomenon with large-scale circulation of winds around a central region of high atmospheric pressure. They rotate clockwise in the northern hemisphere, and counterclockwise in the southern hemisphere. The Little Red Spot shows very little color, just a pale brown smudge in the center. The color is very similar to the surroundings, making it difficult to see as it blends in with the clouds nearby. Citizen scientists Gerald Eichstaedt and John Rogers processed the image and drafted the caption.

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A Saturn moon makes waves

9:57 am

Daphnis makes waves

Cool image time! The image above, taken on January 16, 2017 during one of Cassini’s ring-grazing passes as it enters its last year at Saturn, has been reduced and cropped to post here. It shows clearly the waves caused by the gravity of the moon Daphnis as its travels within a gap in the rings of Saturn.

Daphnis (5 miles or 8 kilometers across) orbits within the 42-kilometer (26-mile) wide Keeler Gap. Cassini’s viewing angle causes the gap to appear narrower than it actually is, due to foreshorteneing. The little moon’s gravity raises waves in the edges of the gap in both the horizontal and vertical directions.

The image also shows many details about Daphnis itself, including a ridge at its equator that is thought to be an accumulation of material gathered from the rings.

The strangeness of Saturn’s rings is well illustrated here. Though made up of many solid particles, as a group the rings act almost like liquid. Note for example the ring on the far side of Daphnis. Its edge gets pulled out slightly as the moon goes by, but then the gravity of the rest of the ring pulls it back.

The universe is a wonderful place, as it is. No need to make up stuff (such as faces on Mars or fake civilizations on the Moon), as our imagination is probably insufficient to match the weirdness that is really out there.

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