Tag: science

Mars’ mysterious slope streaks become even more mysterious

10:10 am

Bright slope streaks in Arabia Terra
Click for full image.

Mars is an alien planet. This fact needs to be restated over and over, because we humans have an uncontrolled and unconscious tendency to view the things we find on Mars and assume they are caused by and resemble phenomenon we see all the time here on Earth.

Not. Mars has a very different climate, a significantly weaker gravitational field (about one third of Earth’s), and a geological and environmental make-up very alien from Earth’s. While many phenomenon there might have parallels on Earth, it is very dangerous to assume they are the same, because more often than not, they are exceedingly dissimilar and mysterious.

The image on the right is another example of this, reduced and cropped to post here. It is of some slope streaks in the Arabia Terra region on Mars, the largest most extensive region in the transition zone between the northern lowland plains and the southern highlands. I found it in my review of the August 30th release of new images from the high resolution camera on Mars Reconnaissance Orbiter.

As I already noted in my previous article about the mysterious slope streaks of Mars:

The bottom line, as noted in one paper, “The processes that form slope streaks remain obscure. No proposed mechanism readily accounts for all of their observed characteristics and peculiarities.”

Mars is strange. Mars is alien. Mars epitomizes the universe in all its glory.

The image above only reinforces this conclusion.
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Hayabusa-2 in safe mode for one day on August 29

9:36 am

Japan’s Hayabusa-2 space probe automatically entered safe mode for one day on August 29, causing engineers to postpone a planned operation set for Sept 5.

Hayabusa2 is equipped with four reaction wheels that are used to control the posture of the spacecraft, and posture control is usually performed using three of these reaction wheels. On August 29, the back-up reaction wheel that has not been used since October last year was tested, and an abnormal value (an increased torque) as detected. The spacecraft therefore autonomously moved into the Safe-Hold state. Details of the cause of the abnormal torque value are currently under investigation. On August 30, restoration steps were taken and the spacecraft returned to normal. However, as the spacecraft moved away from the home position due to entering Safe-Hold, we are currently having to return to the home position. We will return to the home position this weekend.

The attitude of the spacecraft is controlled by three reaction wheels as before. Entering the Safe-Hold state is one of the functions employed to keep the spacecraft safe, which means that procedures have worked normally.

In this case it is very clear that this event actually demonstrated that the spacecraft’s systems are operating properly to prevent it from becoming lost. However, the event also underlined the urgency of getting its samples from the asteroid Ryugu back to Earth.

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Has Yutu-2 found something unusual?

9:08 am

According to Chinese sources, China’s lunar rover Yutu-2 has spotted something unexpected and unusual on the surface of the far side of the Moon.

On July 28, the Chang’e-4 team was preparing to power Yutu-2 down for its usual midday ‘nap’ to protect the rover from high temperatures and radiation from the sun high in the sky. A team member checking images from the rover’s main camera spotted a small crater that seemed to contain material with a color and luster unlike that of the surrounding lunar surface.

The drive team, excited by the discovery, called in their lunar scientists. Together, the teams decided to postpone Yutu-2’s plans to continue west and instead ordered the rover to check out the strange material. With the help of obstacle-avoidance cameras, Yutu-2 carefully approached the crater and then targeted the unusually colored material and its surroundings. The rover examined both areas with its Visible and Near-Infrared Spectrometer (VNIS), which detects light that is scattered or reflected off materials to reveal their makeup.

VNIS is the same instrument that detected tantalizing evidence of material originating from the lunar mantle in the regolith of Von Kármán crater, a discovery Chinese scientists announced in May.

So far, mission scientists haven’t offered any indication as to the nature of the colored substance and have said only that it is “gel-like” and has an “unusual color.” One possible explanation, outside researchers suggested, is that the substance is melt glass created from meteorites striking the surface of the moon.

The report is at present too vague to really tell us anything. What I predict is that this discovery will almost certainly not be as strange or alien as this report makes it sound.

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Scientists look at and compare two past grand minimums

11:55 am

In a new paper just published by the American Geophysical Union (AGU), scientists have used tree ring data to analyze and compare the last two past grand minimums, dubbed the Spörer Minimum (1432–1578) and the more well known Maunder Minimum (1640–1720).

The link takes you to the full paper. It is very technical but what it essentially finds is that there appear to be some differences between the two, but more important, during the deepest part of both grand minimums all evidence of the 11 year sunspot cycle (dubbed the Scwabe cycle) vanishes.

A detailed comparison between the Spörer and Maunder (CE 1640–1720) minima shows that the Spörer Minimum is associated with enhanced Δ14C variability in a band centered around the 11‐year Schwabe cycle from CE 1450 to 1479 and between CE 1545 and 1578, whereas little 11‐year variability is observed from CE 1479 to 1539. In contrast, we only observe enhanced 11‐year variability after the end of the Maunder Minimum at CE 1722–1744, which could indicate that the nature and origin of the two minima were different.

In other words, from 1479 to 1539 (Spörer) and 1545 to 1722 (Maunder) the data suggests that we would not have seen sunspots, even with today’s superior observational capabilities.

They base this conclusion by looking at carbon-14 data, which reflects the arrival of cosmic rays on the Earth. When the sun is active cosmic rays decrease. When it is inactive, with no sunspots, cosmic rays increase. This data can be compared with known and more recent sunspot cycles, and can thus provide a robust baseline for determining what the Sun’s behavior was like before the era of the telescope.

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China’s FAST radio telescope discovers 93 new pulsars

9:53 am

The research team running China’s FAST radio telescope, the largest single dish such telescope in the world, have announced that they have discovered 93 new pulsars since October 2017.

China might still be having trouble finding a big name astronomer to run the telescope, but in the meantime it looks like their own people are taking advantage of the situation to use the telescope establish their own names.

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OSIRIS-REx’s four candidate landing sites

9:07 am

The OSIRIS-REx engineering team has released a short video that flies over in close-up, showing the spacecraft’s four candidate sites on the asteroid Bennu, one of which will be where they will do a touch-and-go sample grab.

They continue to accumulate data on the four sites, all of which pose issues and risks because of nearby boulders and the looseness of Bennu’s rubble pile make-up.

Though all the sites are being considered, my sources in the industry suggest that the two dubbed Sandpiper and Nightingale are being favored. I like Osprey, because it is inside a crater and looks clear, but then, what do I know?

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Cliff collapse on Mars

2:38 pm

Cliff collapse on Mars
Click for full image.

Cool image time! The photograph to the left, rotated, cropped, and reduced to post here, was found in the August image release of the high resolution camera on Mars Reconnaissance Orbiter (MRO).

This was an uncaptioned image, with a title “Cataract and Grooves in Kasei Valles.” Kasei Valles is the giant canyon north of Marineris Valles. Though it is not as well known or maybe as dramatic, it is about as long and vast as its more famous southern canyon. It also has some very intriguing features, including what I consider to so far be the pit on Mars with the highest priority for exploration.

The image on the right shows the result when a giant section of this cliff face broke off and collapsed into the canyon. It also shows that the collapse occurred a long time ago. Not only are there newer craters on the collapse debris, the breakdown at the cliff base looks well eroded, as if many eons have passed since it piled up there.

When this section broke off however it was a very big event. The width of the collapse is about a mile across, with its depth about 600 feet. The height of the cliff is approximately 3000 feet, give or take a few hundred feet. Thus the chunk that broke off was about 600 feet wide, 5,000 feet long, and about 3,000 feet high. That’s one very big rock.

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NASA Inspector General to Congress: Free Europa Clipper from SLS

8:44 am

In a letter to Congress on August 27, 2019, NASA’s inspector general has called for Congress to immediately abandon the legal requirement it imposed on Europa Clipper to fly on NASA’s SLS rocket, thereby allowing NASA to choose any commercial rocket to launch the spacecraft.

The letter [pdf] is amazingly blunt.

[W]e write to highlight an issue at NASA that we believe requires immediate action by Congress. Language in NASA’s appropriation legislation requires the Agency to launch a satellite to Europa, a moon of Jupiter, in 2023 on the yet-to-be-completed Space Launch System (SLS) rocket. However, because of developmental delays and, more significantly, NASA’s plans to use the first three SLS rockets produced for its Artemis lunar program, an SLS will not be available until 2025 at the earliest. Consequently, if completed on its projected schedule, the approximately $3 billion dollar Europa spacecraft (known as “Europa Clipper”) will need to be stored for at least 2 years at a cost of $3 to $5 million per month until an SLS becomes available. NASA recently added $250 million in Headquarters-held reserves to the project to address these storage and related personnel costs.

Congress could reduce risks to both the Europa mission and Artemis program while potentially saving taxpayers up to $1 billion by providing NASA the flexibility in forthcoming fiscal year (FY) 2020 appropriations legislation to determine the most cost effective and timely vehicle to launch the Europa Clipper mission in 2023 or whenever the satellite is completed.

As blunt as the letter is, the wording above is also very careful to hide the fact that the $1 billion savings will come, not from avoiding the launch delay, but from buying a private commercial launch vehicle (estimated launch cost about $100 million) versus using SLS (estimated launch cost of $1 billion to $4 billion).

Will Congress take this advice? It should, though I am pessimistic. Our Congress has not shown much interest in doing the smart thing when it comes to SLS for about a decade. Why should things change now?

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SpaceX begins hunt for Starship landing sites on Mars

3:07 pm

Candidate landing sites for SpaceX's Starship

In the August image release from the high resolution camera of Mars Reconnaissance Orbiter (MRO) were five images whose title immediately caught my interest:

The overview map on the right shows the location on Mars for these five photographs. The second and third images are of the same location, taken to produce a stereo pair.

To put it mildly, it is most intriguing to discover that SpaceX is beginning to research a place where it can land Starship on Mars. I immediately emailed Nathan Williams, the JPL scientist who requested these images from SpaceX, but he was bound by a non-disclosure agreement with SpaceX and could not comment. I have since tried to get some information directly from SpaceX but so far the company has not responded. A 2017 news story had indicated the company’s interest in this Mars’ location, but gave no details either.

Based on what we now know of Mars, however, it is possible to figure out why they favor this location, on the border between the two large northern lowland plains Arcadia and Amazonis Planitia.
» Read more

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Astronomers find Jupiter-sized exoplanet with comet-like orbit

10:46 am

Worlds without end: Astronomers have discovered a Jupiter-sized exoplanet with an extremely eccentric and comet-like orbit circling a star about 103 light years away.

Astronomers have discovered a planet three times the mass of Jupiter that travels on a long, egg-shaped path around its star. If this planet were somehow placed into our own solar system, it would swing from within our asteroid belt to out beyond Neptune. Other giant planets with highly elliptical orbits have been found around other stars, but none of those worlds were located at the very outer reaches of their star systems like this one.

This discovery, like so many others, illustrates again our lack of knowledge about the make-up and formation of solar systems. According to modern formation theories, you shouldn’t get such a large exoplanet in such an eccentric orbit. But here we are.

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Assembly complete on Europe’s Franklin Mars rover

10:32 am

Engineers have completed the assembly of Europe’s Rosalind Franklin rover that is scheduled for launch to Mars in July 2020

Rosalind Franklin, which is the result of cutting edge work from UK, European and Canadian scientists and engineers will now be shipped from the Airbus factory in Stevenage, Hertfordshire to Toulouse in France for testing to ensure it survives its launch from Earth next summer and the freezing conditions of Mars when it lands on the planet in March 2021.

Whether they can meet this schedule remains unknown because of the problems that occurred during testing of the spacecraft’s landing parachutes.

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No warming in U.S. since 2005

5:47 pm

NOAA data since 2005
Click for full image.

Using temperature stations specifically picked to eliminate as many biases and temperature errors as possible, NOAA has found that since 2005 the continental United States has experienced no warming at all.

The graph at the right, reduced to post here, illustrates this.

In January 2005, NOAA began recording temperatures at its newly built U.S. Climate Reference Network (USCRN). USCRN includes 114 pristinely maintained temperature stations spaced relatively uniformly across the lower 48 states. NOAA selected locations that were far away from urban and land-development impacts that might artificially taint temperature readings.

Prior to the USCRN going online, alarmists and skeptics sparred over the accuracy of reported temperature data. With most preexisting temperature stations located in or near urban settings that are subject to false temperature signals and create their own microclimates that change over time, government officials performed many often-controversial adjustments to the raw temperature data. Skeptics of an asserted climate crisis pointed out that most of the reported warming in the United States was non-existent in the raw temperature data, but was added to the record by government officials.

The USCRN has eliminated the need to rely on, and adjust the data from, outdated temperature stations. Strikingly, as shown in the graph below, USCRN temperature stations show no warming since 2005 when the network went online. If anything, U.S. temperatures are now slightly cooler than they were 14 years ago.

What is significant about this data is how it reveals the dishonesty of the adjustments that NOAA and NASA have been making to the temperature data. Those adjustments, supposedly done to make the data more accurate, have always cooled the past and warmed the present, a pattern that by itself is very suspicious.

These temperature stations were chosen to create a reliable baseline, picking stations that needed no adjustment and would thus give scientists a measure for justifying any alterations they impose on the raw data. Not only does this data suggest strongly that the claims of global warming year after year (“This year was the hottest on record!”) are suspect, it also shows that there is something seriously wrong with their adjustments. If their modifications to the raw data was correct, then this set of data should have matched it. It does not.

Will this mean they will readjust the overall data to eliminate the cooling in the past and the warming in the near present to make the data better fit what these results prove? Don’t be silly! That would show that there is little merit to the theories of the global warming alarmists, something that cannot be tolerated. It might cause those big government contracts to be cancelled. Worse, it will make it more difficult for these leftists to use the data to justify reshaping society into their vision of a socialist utopia.

No, what I expect to happen is that the scientists at NOAA (who also happen to be the ones who have been tampering with all the other data) to begin altering the temperature data from these baseline stations, to make them fit their theories. Or as Democratic presidential candidate Joe Biden recently put it, “We choose truth over facts.”

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Arecibo gets $19 million NASA research/education grant

5:25 pm

The Arecibo Observatory in Puerto Rico was today awarded an $19 million NASA research/education grant for studying near Earth asteroids.

NASA awarded the University of Central Florida (which manages the site on behalf of National Science Foundation) the four-year grant to observe and characterize near-Earth objects (NEO) that pose a potential hazard to Earth or that could be candidates for future space missions.

…The award also includes money to support STEM education among high school students in Puerto Rico. The Science, Technology And Research (STAR) Academy brings together 30 local high-school students per semester once a week for 16 classes to learn about science and research at the observatory.

This, plus the recent NSF grant, will keep the telescope operating for at least the next few years.

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Global warming scientist Michael Mann loses Canadian lawsuit

5:39 pm

Global warming scientist Michael Mann has lost a Canadian libel lawsuit he had filed against a skeptical scientist who had said that Mann “belongs in the state pen, not Penn State.”

More details here. The court also ruled that Mann must pay the defendant’s court costs. The key quote that proves Mann’s scientific work is either incompetent or fraudulent is this:

Dr Mann lost his case because he refused to show in open court his R2 regression numbers (the ‘working out’) behind the world-famous ‘hockey stick’ graph.

Mann is most well known for his hockey stick graph that eliminated any evidence of the well-documented Medieval Warming Period and thus made it appear global warming only began with the industrial age.

Many good scientists have questioned this graph, including Canadian scientist Dr. Tim Ball, the victorious defendant in this case. The court had demanded that to prove Ball’s statement was libel, Mann had to show everyone the legitimate scientific methods he used to create the graph. Mann refused to do so, and so the court ruled against him.

I should add that a number of different scientists have analyzed Mann’s hockey stick graph and have found that, based on the information in Mann’s own published papers, they could plug the data in and with his methods create any graph they wanted, essentially demonstrating that what Mann did was junk.

Does this prove human-caused global warming isn’t happening? No, it doesn’t. What it does demonstrate once again is that another one of the icons of that theory is either a fraud or incompetent, and that his work is not worth the electrons used to publish it. In the case of Mann, the evidence of his political biases and corrupt science practices has been evident for years, first exposed in his emails in the climategate emails. There, he actually worked to destroy the careers of any scientist who questioned his work, rather than debate the facts with them.

He tried to do the same this time with Dr. Ball, and has been soundly slapped down.

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Curiosity’s future travels

9:42 am

Curiosity's planned route up Mt Sharp
Click for full image.

The Curiosity science team has released a new map showing an update of their planned route for Curiosity in the coming year or so, showing how they plan on leaving Gediz Vallis Channel after spending some time exploring the numerous geological layers exposed on its eroded surface.

The new information in this map is the route near the bottom of the image, showing more precisely the route up the canyon and then their retreat through the gap in the canyon’s western wall.

To get a better idea of what this means, I have updated my annotations on this Mars Reconnaissance Orbiter image of Gediz Vallis Channel, posted previously in my May 30, 2019 rover update.
» Read more

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At a conference today

8:33 am

Posting will be intermittent, as I am attending a one day conference [pdf] at the University of Arizona being put on by Lunar & Planetary Laboratory.

Tidbits posted as I hear them (these tidbits do not involve new results that are still embargoed):

-Data from OSIRIS-REX at Bennu and Hayabua-2 at Ryugu have found that while both are rubble pile asteroids, there is evidence that suggests that Ryugu, but not Bennu, was subjected to heating in the past. In other words, it had been cooked.

-We presently possess no meteorites with a chemical make-up that matches the data obtained from orbit around Mercury. This isn’t a surprise, as any material thrown from the surface by an impact would not likely have the energy and velocity required to climb up out of the Sun’s gravitation well and get to Earth. Material from Mars however can easily fall into that well, which is why it is not difficult to find meteorites from Mars on Earth.

– Unlike the Earth, where atmospheric circulation in the north and south hemispheres is independent, Titan’s atmosphere is actually one large Hadley Cell, with flow going from one hemisphere to the other, depending on season.

-The evolutionary changes in Neptune’s orbit over time is thought to have caused the high inclination orbits seen in the objects in the Kuiper Belt, which are a mystery since all these objects must have once been confined within the protoplanetary disk, today’s plane of the solar system.

-Despite finding thousands of candidate exoplanets, Kepler found none in the habitable zone. This does not mean habitable exoplanets are rare, but that there were certain biases in Kepler’s observations that caused this lack.

-There is a lot of research going on to study buried ice/glaciers here on Earth. This work is directly aimed at better understanding the many buried glaciers now thought to exist on Mars.

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Melting rocks on Mars

2:28 pm

Melt pools near Mohave Crater
Click for full image.

Cool image time! The image to the right, reduced, cropped, and annotated by me to post here, was part of the July image download from the high resolution camera on Mars Reconnaissance Orbiter (MRO) and was titled “Melt Pools around Mojave Crater”.

You can see that the flow began to the south, flowed northward (in the middle of the image), and then pooled in the two places as indicated. In the full photograph you can also see that the flow continued to the north, forming more pools.

The title to me suggests that this flow and the melt pools were lava, not ice. The low latitude, 7 degrees north, also suggests this is not ice. Though I was unable to reach the person who requested these images, it appears his research is aimed understanding the melt events that occur in the vicinity of craters upon impact. From his website:
» Read more

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Scientists resolve one Mars methane mystery

9:20 am

Scientists have now figured out why the methane data from Curiosity on the Martian surface did not match the methane data from Trace Gas Orbiter in orbit around Mars.

Last year, scientists learned that methane concentrations changed over the course of the seasons with a repeatable annual cycle. “This most recent work suggests that the methane concentration changes over the course of each day,” Dr Moores said. “We were able – for the first time – to calculate a single number for the rate of seepage of methane at Gale crater on Mars that is equivalent to an average of 2.8 kg per Martian day.”

Dr Moores said the team was able to reconcile the data from the ExoMars Trace Gas Orbiter and the Curiosity Rover, which appeared to contradict each other with wildly different detections of methane. “We were able to resolve these differences by showing how concentrations of methane were much lower in the atmosphere during the day and significantly higher near the planet’s surface at night, as heat transfer lessens,” he said.

Solving that data conflict helps them get a better grip on the real question: Why is the methane fluctuating in this manner?

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An eroding Martian glacier?

1:11 pm

An eroded glacier on Mars?

Close-up of an eroded glacier on Mars?
Click for full image.

Cool image time! In my never-ending review of new images downloaded each month from the high resolution camera of Mars Reconnaissance Orbiter (MRO), I came upon an image dubbed merely “Terrain Sample” in the August release. To the right, cropped and rotated to post here, is the weird terrain from that image, with the section in the white box shown below at full resolution.

To keep MRO functioning properly, they need to take images on a regular basis, even if they have no planned features coming into view. As noted by Singleton Thibodeaux-Yost, the HiRISE Targeting Specialist at the University of Arizona who requested this image,

It was not taken in response to a suggestion from the public or our team database. This image was a ride-along with another instrument on MRO. [The scientists for that other instrument] targeted this region for a particular reason and we just turned on our camera as well to gather more data while they collected their data. I title these types of images “terrain sample” as we don’t always know what the results will be.

In other words, the scientists running the high resolution camera have no inkling what they will see until see it.

This image shows the inside rim of a crater, with the crater rim to the south just beyond the image’s bottom edge. This somewhat large crater is located in the middle of Arabia Terra, one of the largest regions of the transition zone between the southern highlands and the northern lowlands (where some scientists believe an intermittent ocean might have once existed). This transition zone has many features that suggest a tidal basin on the edge of that ocean.

A few months ago I would have been entirely baffled by what we see here. I might have speculated that these strange features were another variation of that shoreline region. Maybe these features are the erosion one sees on a dried lakebed after the water has drained away.

I might have also speculated that these shapes looked like the kind of frozen ice blocks one sees in the icecap of the Arctic here on Earth.

Both speculations then would have been complete guesses.

I now know, based on things I have recently learned in writing about several other images from MRO, that the second guess is likely right (though of course my opinion as a very amateur planetary geologist should not be taken very seriously). My reasons?
» Read more

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Data suggests Earth-sized exoplanet has no atmosphere and resembles Mercury

9:11 am

Using archive data from the Spitze Space Telescope astronomers believe that an Earth-sized exoplanet about 49 light years away probably has no atmosphere and is likely similar to Mercury.

Discovered in 2018 by NASA’s Transiting Exoplanet Satellite Survey (TESS) mission, planet LHS 3844b is located 48.6 light-years from Earth and has a radius 1.3 times that of Earth. It orbits a small, cool type of star called an M dwarf – especially noteworthy because, as the most common and long-lived type of star in the Milky Way galaxy, M dwarfs may host a high percentage of the total number of planets in the galaxy.

…The Spitzer observations rule out an atmosphere with more than 10 times the pressure of Earth’s. (Measured in units called bars, Earth’s atmospheric pressure at sea level is about 1 bar.) An atmosphere between 1 and 10 bars on LHS 3844b has been almost entirely ruled out as well, although the authors note there’s a slim chance it could exist if the stellar and planetary properties were to meet some very specific and unlikely criteria. They also argue that with the planet so close to a star, a thin atmosphere would be stripped away by the star’s intense radiation and outflow of material (often called stellar winds).

For a planet to be in the habitable zone of a M dwarf it must orbit very close to the star. This research suggests that conditions that close to the star might still preclude the possibility of life.

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Second gas giant found orbiting Beta Pictoris

9:04 am

Astronomers today announced that they have detected another exoplanet orbiting the young star Beta Pictoris 63 light years away.

This time, the team had to analyse more than 10 years of high-resolution data, obtained with the HARPS instrument at ESO’s La Silla Observatory in Chile, in order to indirectly detect the presence of β Pictoris c. This second giant planet, which has a mass nine times that of Jupiter, completes its orbit in roughly 1,200 days, and is relatively close to its star (approximately the distance between the Sun and the asteroid belt, whereas β Pictoris b is 3.3 times more distant).

Because Beta Pictoris has a very large disk of material, astronomers have expected to find exoplanets there for decades. Only in the last two decades have their instruments improved enough to allow the detections. Moreover, because the star is young, astronomers believe it gives them a glimpse into what our solar system looked like during its early formation period.

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Parker to extend instrument operations in future solar fly-bys

9:40 am

The engineering and science team for the Parker Solar Probe have decided they can turn on its science instruments for a longer period during future solar fly-bys, and have now done so for its upcoming third approach.

Parker Solar Probe turned on its four instrument suites on Aug. 16, 2019 — earlier than during its previous two solar encounters, extending the observation period from 11 days to about 35 days.

During the spacecraft’s first two solar encounters, the science instruments were turned on when Parker was about 0.25 AU from the Sun and powered off again at the same distance on the outbound side of the orbit. (One AU, or astronomical unit, is about 93 million miles, the average distance between the Sun and Earth.) For this third solar encounter, the mission team turned on the instruments when the spacecraft was around 0.45 AU from the Sun on the inbound side of its orbit and will turn them off when the spacecraft is about 0.5 AU from the Sun on the outbound side.

This decision will allow them to get more data about the solar wind from farther from the Sun.

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A directory of skeptical climate websites

11:09 pm

Link here. The list is very comprehensive, including many of the sites I check frequently. Note too that many of these sites are very rigorous in the analysis of data, often far more rigorous than many modern peer-reviewed climate papers I read.

As they are skeptical, so should you be. Don’t take anything said at these sites at face value, but don’t dismiss what they say outright either. Pay attention, because you might find that you will become more discerning in the future when you are bombarded with chicken-little pronouncements from the global warming activist crowd.

One quote from the article bears some contemplating:

Virtually all powerful vested interests in the Western hemisphere recognize climate change alarm as leverage to impose self-serving policies and garner higher profits. The reasons for this are myriad. [The article then lists sixteen such reasons, all well known and well documented.]

Taken individually, each of these reasons—and this list undoubtedly omits additional special interests that benefit from climate change alarm—represent a profound shift in public policy. Each of them represents investments skewing away from optimal returns and instead towards returns that favor a politically entitled group. The overall impact of all of them is regressive, increasing the cost-of-living for the most economically vulnerable populations.

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Juno finds Jupiter’s core more extended and less dense than predicted

11:58 am

My headline above focuses on the real story here, that Juno has found that Jupiter’s solid core is more fuzzy and extended.

Unfortunately, the press release instead focuses on one theory, based on computer models, that might explain this discovery.

The research team ran thousands of computer simulations and found that a fast-growing Jupiter can have perturbed the orbits of nearby “planetary embryos,” protoplanets that were in the early stages of planet formation.

Liu said the calculations included estimates of the probability of collisions under different scenarios and distribution of impact angles. In all cases, Liu and colleagues found there was at least a 40% chance that Jupiter would swallow a planetary embryo within its first few million years. In addition, Jupiter mass-produced “strong gravitational focusing” that made head-on collisions more common than grazing ones.

Isella said the collision scenario became even more compelling after Liu ran 3D computer models that showed how a collision would affect Jupiter’s core. “Because it’s dense, and it comes in with a lot of energy, the impactor would be like a bullet that goes through the atmosphere and hits the core head-on,” Isella said. “Before impact, you have a very dense core, surrounded by atmosphere. The head-on impact spreads things out, diluting the core.”

This theory is all well and good, but we mustn’t take it too seriously. It relies entirely on computer models, and carries with it enormous assumptions about the early solar system that are as yet unproven.

That Jupiter’s core however is fuzzy and extended however is quite fascinating, highlighting once again how little we know about the universe.

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Jupiter’s changing Great Red Spot, as seen by Juno

9:28 am

Montage of Jupiter's Great Red Spot since 2017
Click for full image.

Citizen scientist Björn Jónsson has compiled the montage to the right, reduced to post here, of the five times Jupiter’s Great Red Spot (GRS) was imaged by Juno during its repeated orbital fly-bys.

The mosaics show how the GRS and nearby areas have changed over the course of the Juno mission. The mosaics cover planetographic latitudes 4.7 to 38 degrees south.

The resolution of the source data is highly variable and this can be seen in some of the mosaics. The viewing geometry also varies a lot. Some of the images were obtained almost directly above the GRS (in particular some of the perijove 7 images) whereas other images were obtained at an oblique viewing angle (in particular the perijove 17 images).

These are approximately true color/contrast mosaics but there may be some inaccuracies in areas where the original images were obtained at a highly oblique angle. The contrast is also lower in these areas.

Some of the changes are remarkable, considering the short time involved. For example, note the appearance of the large white storm below the Spot in the third image, taken in December 2018. It wasn’t there in April 2018, and was gone by Feburary 2019. This doesn’t mean it had dissipated. Instead, the storm is in a different band which moves at a different speed than the band that the Spot is in. It has thus simply moved away.

This movement is even more remarkable when we remember that the Great Red Spot is about the width of the Earth.

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Arecibo gets $12.3 million NSF grant

8:40 am

The National Science Foundation has awarded the Arecibo radio telescope in Puerto Rica a $12.3 million grant to pay for needed repairs and upgrades following the hurricane damage from 2017.

The money will pay for the following work:

  • Repairing one of the suspension cables holding the primary telescope platform, ensuring long-term structural integrity of one of the main structural elements of the telescope.
  • Recalibrating the primary reflector, which will restore the observatory’s sensitivity at higher frequencies.
  • Aligning the Gregorian Reflector, improving current calibration and pointing.
  • Installing a new control system for S band radar, which is part of the microwave band of the electromagnetic spectrum.
  • Replacing the modulator on the 430 MHz transmitter, increasing consistency of power output and data quality.
  • Improving the telescope’s pointing controls and data tracking systems.

Most of this looks to be very basic maintenance, which suggests the telescope is still very starved for funds.

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Amateur finds moon orbiting comet in Rosetta archive

9:46 am

In mining the Rosetta archive of images of Comet 67P/C-G, an amateur astronomer has discovered a twelve-foot-diameter chunk of material that had broken from the comet and was in orbit around it.

Modelling of the Rosetta images indicates that this object spent the first 12 hours after its ejection in an orbital path around 67P/C-G at a distance of between 2.4 and 3.9 km from the comet’s centre. Afterwards, the chunk crossed a portion of the coma, which appears very bright in the images, making it difficult to follow its path precisely; however, later observations on the opposite side of the coma confirm a detection consistent with the orbit of the chunk, providing an indication of its motion around the comet until 23 October 2015.

While it is not really unusual for their to be small objects in the coma of the the comet, orbiting it, this is apparently the largest so far found. That they missed it initially is also not surprising, considering the amount of data they were gathering in such a short time.

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OSIRIS-REx team picks four finalist sample return sites on Bennu

3:31 pm

After months of photographing and analyzing the very rocky-shrewn surface of the rubble-pile asteroid Bennu, the OSIRIS-REx team has chosen four finalist sites, one of which they will do a touch-and-go sample grab.

This fall, OSIRIS-REx will begin detailed analyses of the four candidate sites during the mission’s reconnaissance phase. During the first stage of this phase, the spacecraft will execute high passes over each of the four sites from a distance of 0.8 miles (1.29 km) to confirm they are safe and contain sampleable material. Closeup imaging also will map the features and landmarks required for the spacecraft’s autonomous navigation to the asteroid’s surface. The team will use the data from these passes to select the final primary and backup sample collection sites in December.

The second and third stages of reconnaissance will begin in early 2020 when the spacecraft will perform passes over the final two sites at lower altitudes and take even higher resolution observations of the surface to identify features, such as groupings of rocks that will be used to navigate to the surface for sample collection. OSIRIS-REx sample collection is scheduled for the latter half of 2020, and the spacecraft will return the asteroid samples to Earth on Sept. 24, 2023.

They given the four sites the names Nightingale, Kingfisher, Osprey and Sandpiper.

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