Tag: science

Cryptic terrain in Martian high southern latitudes

12:09 pm

Cryptic terrain in Reynolds Crater near Mars south pole

Cool image time! The image on the right is a small cropped section from a larger image taken of the floor of Reynolds Crater, near the margins of the Martian southern polar carbon dioxide icecap.

The image was part of the August 1, 2018 image release from the high resolution camera on Mars Reconnaissance Orbiter (MRO) and was taken on July 5, 2018. Because that was during the peak of now clearing global dust storm, a large majority of MRO’s images were obscured. Only images taken at high latitudes appeared clear and sharp.

The image link, which has no caption, calls this “cryptic terrain.” Since this is at the margin of the polar cap, the white areas are almost certainly still-frozen dry ice. The white strip down the center of the image appears to be a low drainage gully, made even more evident on the full image.

What are the dark spots however? These are probably related to the dark spiders that appear wherever the carbon dioxide starts to melt and evaporate into gas, releasing the darker dust from below to coat the surface. The dark spots in this image are probably that same darker dust, but why it is scattered about as spots and splotches is a mystery. It does appear that the dark areas more completely cover the higher terrain, but why and if so is definitely unclear.

Back in 1999 I attended a press conference just prior to the failure of Mars Polar Lander. One of the mission’s investigators explained that, based on the orbiter images available at the time, they expected the lander to see some very weird land forms once it reached the surface, shaped in ways that are not seen on Earth. Unfortunately, contact with the spacecraft was lost just before it entered the Martian atmosphere, and was never recovered.

This image however remains me of that scientist’s lost expectation. The seasonal growth and retreat of the Martian icecaps will likely create some strange geology, which is only hinted at in this particular MRO image.

Leave a comment

A different type of color scale for maps that the color-blind can read

11:34 am

Scientists have devised a different type of color scale for scientific maps that makes them more readable for the color-blind.

Data visualizations using rainbow color scales are ubiquitous in many fields of science, depicting everything from ocean temperatures to brain activity to Martian topography. But cartographers have been arguing for decades the “Roy G. Biv” scale makes maps and other figures difficult to interpret, sometimes to the point of being misleading. And for the those with color blindness, they are completely unintelligible.

Now scientists at a U.S. Department of Energy laboratory have developed a color scale that is mathematically optimized to be accurate for both color blind people and those with normal vision. The scale was described Wednesday in a new study in PLOS ONE. “People like to use rainbow because it catches the eye,” says lead author Jamie Nuñez, a chemical and biological data analyst at the Pacific Northwest National Laboratory (PNNL). “But once the eye actually gets there and people are trying to figure out what’s actually going on inside of the image, that’s kind of where it falls apart.”

Ditching this multicolored scale may even save lives. Harvard University researchers found that when traditional rainbow-colored 3-D computer models of arteries were replaced by 2-D models using a red-to-black color scale (pdf), doctors’ accuracy in diagnosing heart disease jumped from 39 percent to 91 percent.

For planetary scientists, changing from the rainbow scale will be difficult. Topography maps especially have for almost a century have shown low regions as blue with high regions as red. This is what scientists, and even ordinary people, have come to expect.

Still, to make these maps understandable to the colorblind seems smart. I wonder if the idea will catch on.

Hat tip from reader Milt Hays Jr.

2 comments

Ceres’ internal structure

10:21 am

The Dawn science team has released their first artist’s concept of the interior of Ceres, based on data gathered by the spacecraft.

Using information about Ceres’ gravity and topography, scientists found that Ceres is “differentiated,” which means that it has compositionally distinct layers at different depths. The most internal layer, the “mantle” is dominated by hydrated rocks, like clays. The external layer, the 24.85-mile (40-kilometer) thick crust, is a mixture of ice, salts, and hydrated minerals. Between the two is a layer that may contain a little bit of liquid rich in salts, called brine. It extends down at least 62 miles (100 kilometers). The Dawn observations cannot “see” below about 62 miles (100 kilometers) in depth. Hence, it is not possible to tell if Ceres’ deep interior contains more liquid or a core of dense material rich in metal.

The most intriguing part of this concept is the existence of a brine layer below the crust. I suspect it is this layer that they believe is the source of the white salty brine that produces Ceres’ ice volcanoes and bright spots.

Leave a comment

One “tiny” storm on Jupiter

9:35 am

A

Cool image time! The image on the right, cropped to post here, shows the white center of one of the smaller giant storms on Jupiter, taken by Juno. The image was processed by citizen scientists Gerald Eichstädt and Seán Doran. If you click on the image you can see the entire picture, which has a host of spectacular details surrounding the white spot.

Unfortunately, they do not provide a scale. Based on past experience, I would guess that this tiny storm probably exceeds the size of the Earth. What makes the image so impressive however are the white cloudtops visible as they swirl around the storm’s center. Sunlight shadows clearly shows that these thunderheads rise above rest of the storm.

The full image shows even more fascinating details. It is worthwhile studying, though one can certainly get lost in that vast and turbulent Jupiter atmosphere.

Leave a comment

The failed Arctic Ocean predictions of global warming scientists

12:01 pm

Link here. The post at the link carefully documents the endless numbers of failed doomsday predictions foisted upon us for the past decade, claiming that due to global warming the Arctic Ocean icecap would be gone by 2018.

Instead, in the past three years there is evidence that the icecap has begun to thicken and expand, recovering from a two decade decline. Though this is not a certain conclusion, what is certain is that there is no sign of the icecap vanishing, in any sense. Every prediction documented at the link, by so-called experts, is completely bogus.

There is a reason the public does not take global warming very seriously. Its advocates have cried wolf too many times. Their predictions of doom have consistently failed. Every. Single. Time.

11 comments

Curiosity successfully drills another hole

10:05 am

Successful drill hole on Vera Rubin Ridge

Curiosity has finally drilled its first successful hole in the geology layer found on Vera Rubin Ridge.

This weekend’s plan is focused on the Stoer drill hole, the tailings derived from the drill and on portion characterization observations. The portion characterization is done prior to sending samples to the analytical instruments, SAM and CheMin, to ensure that the materials will not pose any threat to the instruments. ChemCam passive and Mastcam multispectral imaging will be taken of the drill tailings, to identify any potential differences between the surface and material from deeper within the drill hole. The ChemCam laser (LIBS) will be used to characterize the Stoer drill hole and a bedrock target “Greian,” which appears to show some colour variations. Mastcam will provide colour documentation for Greian.

In order to find rock soft enough on Vera Rubin Ridge, they had to once again retrace their route, retreating back down off the ridge slightly, to a lower point. The image on the right, cropped to post here, shows the drill hole. If you click on the image you can see the full picture.

With this successful drilling, I suspect they will now finally cross Vera Rubin Ridge and head up Mount Sharp.

2 comments

The on-going vicious debate over dinosaur extinction

10:26 pm

Link here. The article is a very well-written and detailed description of the large doubts held by many paleontologists about the theory that a single asteroid/comet impact in Mexico caused the entire dinosaur extinction 65 million years ago. Key quote:

Ad hominem attacks had by then long characterized the mass-extinction controversy, which came to be known as the “dinosaur wars.” Alvarez [the man who first proposed the impact theory] had set the tone. His numerous scientific exploits—winning the Nobel Prize in Physics, flying alongside the crew that bombed Hiroshima, “X-raying” Egypt’s pyramids in search of secret chambers—had earned him renown far beyond academia, and he had wielded his star power to mock, malign, and discredit opponents who dared to contradict him. In The New York Times, Alvarez branded one skeptic “not a very good scientist,” chided dissenters for “publishing scientific nonsense,” suggested ignoring another scientist’s work because of his “general incompetence,” and wrote off the entire discipline of paleontology when specialists protested that the fossil record contradicted his theory. “I don’t like to say bad things about paleontologists, but they’re really not very good scientists,” Alvarez told The Times. “They’re more like stamp collectors.”

Scientists who dissented from the asteroid hypothesis feared for their careers. Dewey McLean, a geologist at Virginia Tech credited with first proposing the theory of Deccan volcanism, accused Alvarez of trying to block his promotion to full professor by bad-mouthing him to university officials. Alvarez denied doing so—while effectively bad-mouthing McLean to university officials. “If the president of the college had asked me what I thought about Dewey McLean, I’d say he’s a weak sister,” Alvarez told The Times. “I thought he’d been knocked out of the ball game and had just disappeared, because nobody invites him to conferences anymore.” Chuck Officer, another volcanism proponent, whom Alvarez dismissed as a laughingstock, charged that Science, a top academic journal, had become biased. The journal reportedly published 45 pieces favorable to the impact theory during a 12-year period—but only four on other hypotheses. (The editor denied any favoritism.)

In 1999, almost twenty years ago, I wrote a long article for a magazine called The Sciences describing this very same debate, including the efforts at the journal Science to push the impact theory and damage the careers of any dissenters. At the time I found the doubts by paleontologists to be widespread, backed up by lots of very credible evidence, including the fundamental data from the fossil record, which simply did not show an instantaneous extinction.

I also discovered that the planetary science community and many in the press were responding not with good science but with ad hominem attacks aimed at destroying anyone who disagreed with the impact theory. I also discovered that the editor at The Sciences who was assigned to edit my piece did not want me to reveal these facts. He was very liberal, had bought into the impact theory, as well as global warming, and like so many liberals I have met in my life he preferred squelching facts rather than allowing the facts to speak. In this case, he was not the editor in charge, and was unable to prevent my article’s publication, as I wanted it written.

Now twenty years later, the same debate continues, though under the radar because of the successful public relations effort by those on the impact theory side to bury the debate. If you were to ask almost any ordinary citizen what caused the extinction of the dinosaurs, they would immediately say a asteroid/comet impact, and would assume that all scientists agree. Sadly, that is not the case, and has never been the case.

Read the article. It details this story quite nicely, and reveals once again the corruption that began permeating the science community in the 1980s and now warps so much research.

12 comments

ULA’s Delta-4 Heavy successfully launches the Parker Solar Probe

12:43 am

ULA’s Delta-4 Heavy has successfully launched the Parker Solar Probe.

As I write this the spacecraft is in orbit, but there are several more steps needed to confirm the spacecraft is on course, including a second burn of the upper stage, its separation from the spacecraft, followed by the firing of the solid rocket kick stage and then its separation from the spacecraft. All these steps will take another 40 minutes or so, so reporting them will have to wait until tomorrow.

Update: The spacecraft has successfully separated from its last stage and is on its way.

Over the next two months, Parker Solar Probe will fly towards Venus, performing its first Venus gravity assist in early October – a maneuver a bit like a handbrake turn – that whips the spacecraft around the planet, using Venus’s gravity to trim the spacecraft’s orbit tighter around the Sun. This first flyby will place Parker Solar Probe in position in early November to fly as close as 15 million miles from the Sun – within the blazing solar atmosphere, known as the corona – closer than anything made by humanity has ever gone before.

The leaders in the 2018 launch standings:

22 China
15 SpaceX
8 Russia
6 ULA
4 Japan
4 Europe

The U.S. and China are once again tied in the national rankings, 22 each.

4 comments

Parker Solar Probe launch scrubbed two minutes prior to launch

5:39 pm

The launch of the Parker Solar Probe on a ULA Delta 4-Heavy rocket was scrubbed early this morning two minutes prior to launch.

[A] member of the launch team announced a gaseous helium regulator alarm at T-minus 1 minute, 55 seconds. There was not enough time remaining in the launch window Saturday to resolve the alarm, so launch managers declared a scrub for the day.

In a brief statement, ULA said the launch was scrubbed “due to a violation of a launch limit, resulting in a hold.”

No other information about the gaseous helium system alarm, or the other technical concerns during the countdown, were released by NASA or ULA.

They are going to try again tonight, at 3:31 am Eastern. You can watch it here. The launch window closes on August 23. If they do not launch by then, they will have to wait until May 2019.

The spacecraft will fly closer to the Sun then any spacecraft ever has in order to study the Sun’s corona.

3 comments

No habitable planets for at least one globular cluster

10:17 am

Calculations by astronomers now suggest that the crowded nature of the giant globular cluster Omega Centauri will probably make it impossible for habitable planets to exist there.

In the hunt for habitable exoplanets, Omega Centauri, the largest globular cluster in the Milky Way, seemed like a good place to look. Comprising an estimated 10 million stars, the cluster is nearly 16,000 light years from Earth, making it visible to the naked eye and a relatively close target for observations by the Hubble Space Telescope.

…[T]he cozy nature of stars in Omega Centauri forced the researchers to conclude that [habitable] planetary systems, however compact, cannot exist in the cluster’s core. While our own sun is a comfortable 4.22 light years from its nearest neighbor, the average distance between stars in Omega Centauri’s core is 0.16 light years, meaning they would encounter neighboring stars about once every 1 million years.

“The rate at which stars gravitationally interact with each other would be too high to harbor stable habitable planets,” Deveny said. “Looking at clusters with similar or higher encounter rates to Omega Centauri’s could lead to the same conclusion. So, studying globular clusters with lower encounter rates might lead to a higher probability of finding stable habitable planets.”

Science thus concludes that Isaac Asimov’s classic science fiction short story, Nightfall, is unlikely.

4 comments

Magnetism helps shape Jupiter’s colorful jet stream bands

9:38 am

The uncertainty of science: New computer models, combined with new data from Juno, suggest that magnetism explains why Jupiter’s colored jet stream bands go as deep below the visible cloud-tops as they do.

Dr Navid Constantinou from the ANU Research School of Earth Sciences, one of the researchers on the study, said that until recently little was known about what happened below Jupiter’s clouds. “We know a lot about the jet streams in Earth’s atmosphere and the key role they play in the weather and climate, but we still have a lot to learn about Jupiter’s atmosphere,” he said. “Scientists have long debated how deep the jet streams reach beneath the surfaces of Jupiter and other gas giants, and why they do not appear in the sun’s interior.”

Recent evidence from NASA’s spacecraft Juno indicates these jet streams reach as deep as 3,000 kilometres below Jupiter’s clouds.

Co-researcher Dr Jeffrey Parker from Livermore National Laboratory in the United States said their theory showed that jet streams were suppressed by a strong magnetic field. “The gas in the interior of Jupiter is magnetised, so we think our new theory explains why the jet streams go as deep as they do under the gas giant’s surface but don’t go any deeper,” said Dr Parker.

This theory is intriguing, but very tentative, to put it mildly.

Leave a comment

Computer simulations suggest solar system was partly shaped by star flyby

9:29 am

The uncertainty of science: New computer simulations now suggest that the solar systems outer regions were shaped by the near approach of another sun-like star billions of years ago.

Susanne Pfalzner and her co-workers suggest that a star was approaching the Sun at an early stage, ‘stealing’ most of the outer material from the Sun’s protoplanetary disk and throwing what was left over into inclined and eccentric orbits. Performing thousands of computer simulations they checked what would happen when a star passes very close-by and perturbs the once larger disk. It turned out that the best fit for today’s outer solar systems comes from a perturbing star which had the same mass as the Sun or somewhat lighter (0.5-1 solar masses) and flew past at approximately 3 times the distance of Neptune.

However, the most surprising thing for the researchers was that a fly-by does not only explain the strange orbits of the objects of the outer solar system, but also gives a natural explanation for several unexplained features of our Solar System, including the mass ratio between Neptune and Uranus, and the existence of two distinct populations of Kuiper Belt objects.

An intriguing result, but to put it mildly it carries a great deal of uncertainty. If true, however, it suggests — as does other research — that our solar system might be somewhat unique. The other research into the solar system’s history suggests we have been traveling through galactic quiet regions for a long time, which helped make things more friendly for the development of life. Together all this work says that in the beginning the solar system was in crowded regions, with its later history then drifting into empty regions.

Thus, the history of our solar system within the galaxy might play a very important part in why we are here.

One comment

There were Viking cats

12:02 am

News you can use: New research now suggests that cats spread through human society, with the second wave involving sea-faring people such as the Vikings.

The first wave is a story you’re probably familiar with. When the team looked the mitochondrial DNA – genetic information that’s passed on from the mother only – they found that wild cats from the Middle East and the fertile eastern Mediterranean shared a similar mitochondrial lineage.

This suggests that small wild cats spread through early agricultural communities, because they were attracted to the mice that were attracted to the grains. The farmers likely encouraged their presence, because, let’s face it, those rodent-killing machines would have been mighty cute company.

Then, thousands of years after this, the research points to a separate mitochondrial connection between cats descended from those in Egypt to ones in Eurasia and Africa. “A mitochondrial lineage common in Egyptian cat mummies from the end of the 4th century BC to the 4th century AD was also carried by cats in Bulgaria, Turkey and sub-Saharan Africa from around the same time,” Callaway reports.

This second wave of expansion has been attributed to ancient sea-faring people – farmers, sailors, and Vikings – because the cats were likely encouraged to stay on board to keep their rodent problem in check.

It makes perfect sense. Our ruling lords needed more space, and thus they compelled humans to begin the great explorations that eventually allowed them to conquer the western hemisphere, as well as the internet.

12 comments

Scientists create coldest spot ever on ISS

5:29 pm

Using a compact lab called the Cold Atom Lab and launched to ISS in a Cygnus freighter in May, scientists have now successfully created coldest spot ever.

The government agency created atoms known as Bose-Einstein condensates (BECs) for the first time in orbit to focus on their unusual quantum behavior. A team of astronauts on the International Space Station (ISS) was able to take the Cold Atom Lab (CAL), which was loaded with lasers and a vacuum chamber, to understand how BECs interact with gravity.

…The scientists produced the BECs with temperatures as “as low as 100 nanoKelvin, or one ten-millionth of one Kelvin above absolute zero,” NASA added, in the statement. Zero Kelvin, also known as absolute zero, is the equivalent of minus 459 degrees Fahrenheit. The average temperature of space is approximately 3 Kelvin or minus 454 degrees Fahrenheit.

In a sense, they didn’t so much create a cold spot as create conditions that allowed the Bose-Einstein condensates to form so that they could study them. The article provides some background about this research, which is focused mostly on trying to figure out how to unify quantum mechanics (which explains the interactions at the atomic level) with general relativity (which explains the actions of matter and energy at large scales). Physicists have been trying unify both for decades, with little success.

2 comments

Weird Martian crater?

1:17 pm

Weird crater on Mars

Time for another cool image! The image on the left, cropped to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on May 31, 2018, and shows a very strange layered mesa sitting in what looks like a crater or collapse feature. If you click on the image you can see the entire picture.

The location of this image is out in the middle of the vast northern plains of Mars. This region has few pronounced features, and generally sits at a lower elevation to the rest of Mars. It is suspected by some scientists that an intermittent ocean was once here, and that we are looking at the floor of a now dry sea.

This image was part of the July image release from MRO, and thus included no caption. They simply refer to it as a layered feature. It sits about a half mile (about 800 meters) to the west of a rough and indistinct cliff that drops down into an area of rougher terrain. This suggests that if this was formed by an impact, it cut down into that lower rougher layer, and since the impact there has been some upwelling from below creating the layered mesa.

I would not take my hypothesis very seriously, however. This feature could have nothing to do with an impact. It might also have been a mesa that now sits in a collapsed sinkhole. Or not. I could come up with many theories, all of which are likely wrong. What I do see here is something that geologically is very strange and baffling.

2 comments

Perseid meteor shower this weekend

10:24 am

The annual Perseid meteor shower upcoming on August 12 is expected to be especially good this year because there will be no moon in the sky.

The Perseid meteors seem to come from a single point, the `radiant’, situated in the constellation Perseus, giving the shower its name. This is however just an effect of perspective, as the meteors move parallel to each other, much like drivers see when driving in heavy rain.

The radiant will be visible from around 10pm and at this time there will be the highest chance of seeing `Earth grazing meteors’. These are meteors that skim the Earth’s atmosphere and so have long, blazing tails.

Observers can expect to see a few tens of meteors per hour, or one every few minutes, once darkness has fallen on 12 August. The number of meteors will peak in the early hours of 13 August, when up to around seventy each hour should be visible.

It is worth it to find a nice dark place and stay up all night at least once in your life to watch this shower. Get a nice camp chair that allows you to lie back, make sure you are dressed comfortably, and sit back and enjoy.

One comment

True color images of Pluto and Charon

9:24 am

The New Horizons science team has released mosaic global images of Pluto and Charon, calibrated to capture their true colors as closely as possible.

These natural-color images result from refined calibrations of data gathered by New Horizons’ Multispectral Visible Imaging Camera (MVIC).”That processing creates images that would approximate the colors that the human eye would perceive – bringing them closer to ‘true color’ than the images released near the encounter,” said Alex Parker, a New Horizons science team co-investigator from Southwest Research Institute, Boulder, Colorado.

Because MVIC’s color filters don’t closely match the wavelengths sensed by human vision, mission scientists applied special processing to translate the raw MVIC data into an estimate of the colors that the eye would see. The colors are more subdued than those constructed from the raw MVIC color data, because of the narrower wavelength range sensed by the human eye.

Both images were taken as New Horizons zipped toward closest approach to Pluto and its moons on July 14, 2015; Charon was taken from a range of 46,091 miles (74,176 kilometers) and Pluto from 22,025 miles (35,445 kilometers). Each is a single color MVIC scan, with no data from other New Horizons imagers or instruments added. The striking features on each are clearly visible, from Charon’s reddish north-polar region known as Mordor Macula, to the bright expanse of Pluto’s, nitrogen-and-methane-ice rich “heart,” named Sputnik Planitia.

I must add that these images show only one hemisphere, since the New Horizons flyby did not get a good look at the opposite hemisphere. We won’t know what the other half of both planets look like for many decades.

Leave a comment

The shrinking and growth of the poles of Mars

9:19 am

Using infrared data from several Mars orbiters over a period of a full Martian year, equivalent to two Earth years, scientists have created an animation showing the growth and retreat and regrowth of the carbon dioxide icecaps of the red planet’s two poles.

This animation shows a side-by-side comparison of CO2 ice at the north (left) and south (right) Martian poles over the course of a typical year (two Earth years). This simulation isn’t based on photos; instead, the data used to create it came from two infrared instruments capable of studying the poles even when they’re in complete darkness.

As Mars enters fall and winter, reduced sunlight allows CO2 ice to grow, covering each pole. While ice at the north pole is fairly symmetrical, it’s somewhat asymmetrical during its retreat from the south pole for reasons scientists still don’t understand. Scientists are especially interested in studying how global dust events affect the growth and retreat of this polar ice. Mars’ seasons are caused by a tilt in the planet, resulting in winter at one of the planet’s poles while it’s summer at the other.

I have embedded the animation below the fold.
» Read more

One comment

Aristarchus Crater on the Moon

9:08 am

Aristarchus Crater

Cool image time! The image on the right, reduced in resolution to post here, shows Aristarchus Crater, one of the more geological intriguing locations on the Moon. This oblique image was taken by Lunar Reconnaissance Orbiter (LRO), still operating in lunar orbit. If you click on the image you can see the full resolution image.

Aristarchus crater is 40 kilometers (25 miles) in diameter and 2700 meters (1.7 miles) deep, with a central peak that rises 300 meters (almost a thousand feet) above the crater floor. When LRO pointed back towards the Sun, LROC was able to capture this magnificent view highlighting subtle differences in albedo (brightness). Some of the albedo contrast is due to maturity (young material is generally brighter than older material) and some reveal true differences in rock type. The central peak shows the complexity of what lies beneath the now hardened impact melt sea that filled the bottom of the crater.

The best part however is the close-up they provided of the crater’s central peaks, posted below.
» Read more

11 comments

Tess captures comet, variable stars, asteroids, and Martian light

8:44 am

During its testing period prior to beginning science operations this month, the exoplanet space telescope TESS spotted in one series of images a comet, a host of variable stars, some asteroids, and even the faint hint of some reflected light from Mars.

Over the course of these tests, TESS took images of C/2018 N1, a comet discovered by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) satellite on June 29. The comet, located about 29 million miles (48 million kilometers) from Earth in the southern constellation Piscis Austrinus, is seen to move across the frame from right to left as it orbits the Sun. The comet’s tail, which consists of gases carried away from the comet by an outflow from the Sun called the solar wind, extends to the top of the frame and gradually pivots as the comet glides across the field of view.

In addition to the comet, the images reveal a treasure trove of other astronomical activity. The stars appear to shift between white and black as a result of image processing. The shift also highlights variable stars — which change brightness either as a result of pulsation, rapid rotation, or by eclipsing binary neighbors. Asteroids in our solar system appear as small white dots moving across the field of view. Towards the end of the video, one can see a faint broad arc of light moving across the middle section of the frame from left to right. This is stray light from Mars, which is located outside the frame. The images were taken when Mars was at its brightest near opposition, or its closest distance, to Earth.

The video that was compiled from these images is embedded below the fold.
» Read more

One comment

Sunspot update for July 2018: The Sun flatlines!

10:50 am

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for July 2018. As I do every month, I am posting it below, annotated to give it some context.

This might be the most significant month of solar activity that has been observed since Galileo. Except for two very short-lived and very weak sunspots that observers hardly noted, the Sun was blank for entire month of July. This has not happened since 2009, during the height of the last solar minimum.

What makes this so significant and unique is that it almost certainly signals the return of the next solar minimum, a return that comes more than a year early. The solar cycle the Sun is now completing has only been ten years long. It is also one of the weakest in more than a hundred years. This combination is unprecedented. In the past such a weak cycle required a long cycle, not a short one.
» Read more

9 comments

Rogue giant exoplanet or brown dwarf discovered about 20 light years away

5:16 pm

Using the Jansky VLA radio telescope astronomers have detected evidence of rogue giant exoplanet or brown dwarf about 20 light years away

Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have made the first radio-telescope detection of a planetary-mass object beyond our Solar System. The object, about a dozen times more massive than Jupiter, is a surprisingly strong magnetic powerhouse and a “rogue,” traveling through space unaccompanied by any parent star.

“This object is right at the boundary between a planet and a brown dwarf, or ‘failed star,’ and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets,” said Melodie Kao, who led this study while a graduate student at Caltech, and is now a Hubble Postdoctoral Fellow at Arizona State University.

The data is not sufficient yet to determine whether this is an exoplanet or a brown dwarf. It is big, and it is floating independent of any other objects, which makes it interesting in of itself.

Leave a comment

Mars dust storm blocks Mars Reconnaissance Orbiter images

9:29 am

In my normal routine to check out the periodic posting of new high resolution images from Mars Reconnaissance Orbiter (MRO), the August 1 update brought what at first was a disturbing surprise. If you go to the link you will see that a large majority of the images show nothing by a series of vertical lines, as if the high resolution camera on MRO has failed.

Yet, scattered among the images were perfectly sharp images. I started to look at these images to try to figure out the differences, and quickly found that the sharp images were always of features in high latitudes, while the blurred images were closer to the equator.

The August 1 image release covered the June/July time period, when the on-going Martian dust storm was at its height. The images illustrate also where the storm was most opaque, closer to the equator.

The next few updates, which occur every three weeks or so, should show increasing clarity as the storm subsides. And the storm is subsiding, according to the latest Opportunity update. The scientists have still not re-established contact with the rover, and do not expect to for at least a month or more, but they are finding that the atmospheric opacity at Endeavour Crater seems to be dropping.

Leave a comment

More close-up images of Ceres

9:19 am

Dome and fractures in Occator Crater

Strange image time! The Dawn science team today released a set of new images taken by the spacecraft in its new very close orbit of Ceres. The image on the right is a cropped section of one of those images, and shows some fractures and a dome in Occator Crater. The image was taken from 28 miles altitude, and if you click on it you can see the entire photograph.

What immediately stands out in this image is the strange bright flow on top of the dome. At first glance it looks like someone put a seashell there. In reality I think it is showing us a landslide of bright material flowing downward, towards the top of the image. The flow was significant enough that it piled up as it went down, which is why it created a cliff edge and shadow line at its base.

Everything we see here is influenced by Ceres’s tiny gravity. It is not unusual to see fractures in the floor of a crater, the nature of these fractures and domes is different, and will require a lot of work by scientists to interpret, because of the different environment.

Leave a comment

No water as yet detected on Ryugu

9:05 am

The Hayabusa-2 science team today said that their first preliminary survey of Ryugu has yet to detect evidence of water.

The Japan Aerospace Exploration Agency (JAXA) said Aug. 2 that data collected from the space probe showed no water on the boulders scattered on the surface of Ryugu.

Ryugu is a C-type asteroid, which is rich in carbon. Many C-type asteroids are known to contain moisture in their surface boulders, and experts hoped that Ryugu would be one of them.

Hayabusa-2’s visit has just begun. I still expect surprises.

Leave a comment

Landslide on Mars

12:45 pm

Landslide on Mars

Cool image time! The image on the right, cropped and reduced in resolution to post here, was taken by Mars Reconnaissance Orbiter on May 30, 2018. It shows the remains of a landslide where it appears a huge chunk of the cliff face broke off and then flowed downward, pushing ahead of it more material to produce a tongue of debris more than four miles long. (If you click on the image you can see the full photograph.)

The picture invokes a spectacular single event. When the cliff broke off, it hit the ground below it like a rock would in wet beach mud. Like wet sand, the ground was pushed away in a muddy gloppy mess.

Is this terrain wet however? The location of this landslide provides some intriguing geological context. Below are two context images, showing this landslide’s location on Mars.
» Read more

Leave a comment

Planetary scientists protest use of term “Planet Nine” for unknown planet

9:13 am

A group of planetary scientists have protested the recent use by some of the term “Planet Nine” for the unknown large planet some believe remains undiscovered in an orbit beyond Pluto.

“We the undersigned wish to remind our colleagues that the IAU planet definition adopted in 2006 has been controversial and is far from universally accepted. Given this, and given the incredible accomplishment of the discovery of Pluto, the harbinger of the solar system’s third zone — the Kuiper Belt — by planetary astronomer Clyde W. Tombaugh in 1930, we the undersigned believe the use of the term ‘Planet 9’ for objects beyond Pluto is insensitive to Professor Tombaugh’s legacy.

“We further believe the use of this term should be discontinued in favor of culturally and taxonomically neutral terms for such planets, such as Planet X, Planet Next or Giant Planet Five.”

The planetary scientist community, the people who really should be the ones to determine the proper definition of a planet, has never accepted the IAU planet definition. This protest letter is just more evidence of this fact.

11 comments

Close-up of bright spot in Occator Crater

3:35 pm

Vinalia Faculae in Occator Crater

Cool image time! The Dawn science team today released some new images taken by the spacecraft in its final tight orbit around the dwarf planet Ceres. The image on the right is a cropped section of the full image. It shows some interesting details of part of one of the two bright spots in Occator Crater, dubbed Vinalia Facula, and was taken from a distance of 36 miles.

Other images show small bright spots in another small crater, fractures and interesting patterns in the floor of Occator crater, a dome in Occator Crater suggestive of underground processes pushing up, and other close-ups of its crater walls.

While all of these features are reminiscent of geology on Earth, none are really the same. Ceres’ light gravity and harsh environment, plus its history in the asteroid belt, requires alien processes that only hint at similarities to what we see on Earth.

5 comments

A vegetable grater on Mars

1:44 pm

A vegetable grater on Mars

Cool image time! I honestly can’t think of any better term but “vegetable grater” to describe the strange surface in the image on the right, cropped from the full sized image that was released with the July 11, 2018 monthly release of new images from the high resolution camera on Mars Reconnaissance Orbiter (MRO).

If you click on the image you can see the whole image, which merely shows more of the same terrain over a wider area. When I cropped it, I literally picked a random 450×450 pixel-sized area, since other than slight variations the entire terrain in the full image is as equally rough. The resolution captures objects as big as five feet across.

Looking at the full image there does seem to be flow patterns moving across the middle of the image, but if so these flow patterns had no effect on the surface roughness, other than indicating a very slight difference in the size of the knobs and pits. Overall, very strange.

The location of this place on Mars is in the cratered southern highlands, to the southwest of Hellas Basin, as indicated by the black cross in the image below.
» Read more

2 comments
1 … 119 120 121 122 123 … 271