Tag: science

Chandrayaan-3 enters lunar orbit

9:38 am


Click for interactive map.

India’s Chandrayaan-3 spacecraft today successfully entered lunar orbit, where it will spend the next week or so slowly lowering its orbit in preparation for a landing attempt by its Vikram lander on August 23rd.

Chandrayaan-3 began a roughly 30-minute burn around 9:30 a.m. Eastern, seeing the spacecraft enter an elliptical lunar orbit, the Indian Space Research Organization (ISRO) stated via social media. “MOX, ISTRAC, this is Chandrayaan-3. I am feeling lunar gravity,” ISRO Tweeted. “A retro-burning at the Perilune was commanded from the Mission Operations Complex (MOX), ISTRAC, Bengaluru.”

The spacecraft will gradually alter its orbit with a burn to reduce apolune Sunday, Aug. 6. It will settle into a 100-kilometer-altitude, circular polar orbit on Aug. 17. From here, the Vikram lander will separate from the mission’s propulsion module and enter a 35 x 100-km orbit in preparation for landing.

If the landing attempt is successful, the Pragyam rover will roll off Vikram to operate for about two weeks on the lunar surface in the high southern latitudes of the Moon.

Meanwhile, the Russian lander Luna-25 will launch on August 10th. Since the rocket that launches it and engines it carries are larger than that used by Chandrayaan-3, it will likely land in Boguslawsky crater, before Vikram touches down nearby.

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Engineers regain full control over Voyager 2

3:29 pm

A longshot effort by engineers has succeeded in re-establishing full communications with Voyager 2, launched in 1977 and flying outward at the edge of the solar system.

“The Deep Space Network used the highest-power transmitter to send the command (the 100-kw S-band uplink from the Canberra site) and timed it to be sent during the best conditions during the antenna tracking pass in order to maximize possible receipt of the command by the spacecraft,” Voyager project manager Suzanne Dodd told AFP. This so-called “interstellar shout” required 18.5 hours traveling at light speed to reach Voyager, and it took 37 hours for mission controllers to learn whether the command worked, JPL said in a statement.

The probe began returning science and telemetry data at 12:29 am Eastern Time on August 4, “indicating it is operating normally and that it remains on its expected trajectory,” added JPL.

Based on a weak signal received earlier, engineers were confident that the spacecraft was functioning in good order despite the loss in communications, and would automatically re-orient itself properly when it did an automatic reset in October. This attempt however fixed things now.

Regardless, the spacecraft probably only has a few more more years of operations before its nuclear powered source finally runs out sometime after 2025.

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A hiking paradise on Mars!

12:51 pm

A hiking paradise on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, sharpened, and annotated to post here, was taken on May 21, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows one of Mars’ more impressive mountains with the Sun somewhat low in the western sky, resulting in the long dark shadows on the eastern slopes.

The line is my quick attempt to mark the obvious route that would be taken along that ridge line to get from the bottom to the top. This could be a hiking trail, or a road. In either case, the elevation gain from the bottom of the ridge to the plateau on top would be about 3,900 feet in about a mile and a half, very steep for Earth — at approximately a 26 degree grade — but probably quite doable in the one-third Martian gravity.

The lower end of my proposed route however is hardly the bottom of the mountain. The slope, now alluvial fill made up of dust and debris from above, continues downhill for another 5,400 feet. All told, from top to bottom the elevation gain is about 9,300 feet over 8.5 miles.
» Read more

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Scientists release infrared image of the Ring nebula, taken by Webb

10:23 am

The Ring Nebula, in false color by Webb
Click for original image.

Scientists yesterday released the first false-color infrared image of the Ring nebula taken by the Webb Telescope. That image, cropped to post here, is to the right. From the press release, which is heavy with platitudes but little information:

Approximately 2,600 lightyears away from Earth, the nebula was born from a dying star that expelled its outer layers into space. What makes these nebulae truly breath-taking is their variety of shapes and patterns, that often include delicate, glowing rings, expanding bubbles or intricate, wispy clouds. These patterns are the consequence of the complex interplay of different physical processes that are not well understood yet. Light from the hot central star now illuminates these layers.

Just like fireworks, different chemical elements in the nebula emit light of specific colours. This then results in exquisite and colourful objects, and furthermore allows astronomers to study the chemical evolution of these objects in detail.

It appears this image was produced using Webb’s near infrared instrument. Further data from its mid-infrared instrument has not yet been released. For a Hubble image of the Ring Nebula, in optical light that the human eye sees, go here.

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NASA agrees to let Axiom fly a fourth private manned mission to ISS

10:10 am

NASA and Axiom have now signed a new agreement allowing Axiom to fly a fourth private manned mission to ISS, tentatively scheduled for no earlier than August 2024.

Through the mission-specific order, Axiom Space is obtaining from NASA crew supplies, cargo delivery to space, storage, and in-orbit resources for daily use. The order also accommodates up to seven contingency days aboard the space station. This mission is subject to NASA’s pricing policy for the services that are above space station baseline capabilities.

The order also identifies capabilities NASA may obtain from Axiom Space, including the return of scientific samples that must be kept cold and other cargo, and the capability to use the private astronaut mission commander’s time to complete NASA science or perform tasks for the agency.

The company has already hired SpaceX to provide the transportation to and from ISS, using its Falcon 9 rocket and one of its fleet of four manned Dragon capsules.

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Despite good first images from Euclid, the orbiting telescope has a problem

10:05 am

Even though the first light images from Euclid have been sharp and exactly what astronomers want, the orbiting telescope designed to make a 3D map of billions of galaxies has an issue that will likely put some limits to that map.

When the telescope started booting up, ESA observers were concerned by the appearance of light markings on the first images relayed to Earth. This, it confirmed, was due to sunlight filtering into the telescope, “probably through a tiny gap”.

A correction to Euclid’s position was able to offset this issue. It means that while the ESA is confident Euclid will be fine to proceed with its mapping mission, particular orientations for the telescope may not be possible.

A limitation like this means that the telescope will not being able to look in some directions and get mapping images. Thus, the overall map will have gaps, though it appears at this moment that the scientists think those gaps will not seriously impact the telescope’s overall work. We shall see.

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The dry and mountainous terrain west of Jezero Crater

12:00 pm

The dry and mountainous terrain west of Jezero Crater
Click for original image.

Since my earlier update today about Perseverance and Ingenuity mentioned the very diverse and strange geology known to exist west of Jezero Crater and where the rover is eventually headed, I thought it worthwhile to post another cool image of that terrain.

The picture to the right, rotated, cropped, reduced and sharpened to post here, was taken on May 22, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled a “terrain sample” image, the location was likely chosen by the camera team in order to fill a gap in the camera’s schedule so that they can maintain its proper temperature. Having a gap that put the spacecraft over this region to the west of Jezero was however a great opportunity to get another look at this rocky, mountainous, and very parched terrain, located in Mars’ very dry equatorial regions.
» Read more

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Perseverance snaps new close-up of Ingenuity

10:28 am

Overview map
Click for interactive map.

Ingenuity as seen by Perseverance on August 2, 2023
Ingenuity as seen by Perseverance on August 2, 2023.
Click for original image.

Cool image time! With Perseverance and Ingenuity in the past week getting close together for the first time in months, the Perseverance team naturally turned its high resolution mast cameras at the helicopter. The picture to the right, cropped, reduced, and sharpened to post here, was taken on August 2, 2023 by the rover’s left mast camera, showing Ingenuity only about two hundred feet away.

The blue dot on the overview map above shows Perseverance’s present location, with the green dot marking Ingenuity’s. The picture to the right is therefore looking almost due south. The red dotted line indicates the rover’s planned route, moving towards Neretva Vallis, the gap in the rim of Jezero Crater from which the delta had flowed, eons ago. The rover’s goal is to eventually enter that gap and explore the very diverse and strange geology known to exist outside the crater to the west.

We should also expect even better images of Ingenuity in the next week. Its 54th flight is scheduled for today, in which the engineering team wants to send the helicopter on a simple straight up and down hop of sixteen feet in order to better “localize” the helicopter. With Perseverance less than two hundred feet away, its cameras should be able to assemble a great movie of that flight.

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New software detects its first potentially dangerous asteroid

9:32 am

New software designed to detect asteroids, developed for use with the Rubin Observatory presently being built in Chile, has successfully discovered its first potentially hazardous asteroid (PHA) using data from another smaller operational ground-based telescope.

The discovered asteroid is 600 feet long, large enough to pose a real threat should it ever hit the Earth. Fortunately, the data says that though its orbit can take it as close as 140,000 miles there is no impact likely in the foreseeable future.

When the Rubin telescope begins its planned ten year survey of the entire night sky in 2025, this software is expected to almost triple the number of known potentially-hazardous-asteroids, from 2,350 to almost 6,000.

Funded primarily by the U.S. National Science Foundation and the U.S. Department of Energy, Rubin’s observations will dramatically increase the discovery rate of PHAs. Rubin will scan the sky unprecedentedly quickly with its 8.4-meter mirror and massive 3,200-megapixel camera, visiting spots on the sky twice per night rather than the four times needed by present telescopes. But with this novel observing “cadence,” researchers need a new type of discovery algorithm to reliably spot space rocks.

Thus, the development of this new software.

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The first glacial evidence found on Mars back in 2007

11:36 am

Glaciers on Mars?
Click for original image.

Cool image time! The picture to the right, cropped, reduced, sharpened, and annotated to post here, was taken on January 3, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the eastern wall of what the scientists call a graben, a large depression caused when the ground inside the depression suddenly shifted downward.

The elevation difference between the high and low points is about 3,500 feet. The streaks on the lower half of the cliff wall are slope streaks, a phenomenon unique to Mars that remains at this moment unexplained. Though the streaks resemble avalanches, they do not change the topography in any way, have no debris pile at their base, and appear instead to be a stain that appears at random times of the year that fades with time.

What is intriguing about this picture however is the wavelike floor on its western half. At first glance these waves suggest some form of dust dunes or lava flows, but neither conclusion appears correct. Instead, we are looking at what was one of the first discoveries on Mars of what scientists have determined to be glacial features.
» Read more

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Bones of the biggest ever whale species possibly found?

8:49 am

A big whale?

The uncertainty of science: Paleontologists have discovered a portion of the skeleton of what they claim might be the biggest and heaviest animal ever found, a whale that potentially grew to be as much as twice as big as a blue whale, the largest living species previously known.

A newly described fossilized whale named Perucetus colossus, dating to roughly 38 million years ago, might have been heavier than a blue whale, even if it was not as long. Blue whales, which are endangered, weigh about 100 to 150 tonnes, although some might be as heavy as 200 tonnes. Perucetus colossus was between 85 and 340 tonnes, according to the scientists who found and described the remains: 13 vertebrae, 4 ribs and a bit of pelvis. Their best-guess estimate is that the whale was around 180 tonnes. This mind-boggling mass is the result of its bones, which were big and dense — an evolutionary adaptation that helped it to dive.

The graphic to the right shows the discovered bones in red, with the rest of the theorized skeleton indicated in grey. Only in the article’s next-to-last paragraph does Nature recognize this very very very large uncertainty:

The team chose to create a visual reconstruction of what the whale might have looked like, basing the head on skulls of related basilosaurid species, but they caution that some of the details are speculative. It could have been skinnier. But it also could have been quite a bit longer or fatter, [co-author Eli] Amson says.

In other words, they presently have no idea what the species actually looked like, or how big it actually was. It very well could have been much shorter and thinner than proposed. It appears therefore they chose to highlight the largest possible size to garner the biggest press coverage — which of course they are getting.

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NASA detects weak signal from Voyager 2

8:22 am

Though communications with Voyager 2 have not been re-established, JPL engineers using NASA’s Deep Space Network of antennas have detected a weak signal from Voyager 2 that indicates the spacecraft is still functioning.

Using multiple antennas, NASA’s Deep Space Network (DSN) was able to detect a carrier signal from Voyager 2. A carrier signal is what the spacecraft uses to send data back to Earth. The signal is too faint for data to be extracted, but the detection confirms that the spacecraft is still operating. The spacecraft also continues on its expected trajectory. Although the mission expects the spacecraft to point its antenna at Earth in mid-October, the team will attempt to command Voyager sooner, while its antenna is still pointed away from Earth. To do this, a DSN antenna will be used to “shout” the command to Voyager to turn its antenna. This intermediary attempt may not work, in which case the team will wait for the spacecraft to automatically reset its orientation in October.

The hope is that new commands to re-orient, sent by the strongest signal possible, might be heard by the spacecraft, causing it to obey now. If not, this weak signal from Voyager 2 still suggests that the October reset will occur as normal and engineers will be able to recover communications then.

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Sunspot update: In July the Sun continued its high sunspot activity

5:05 pm

Today NOAA released its monthly update of its graph that tracks the number of sunspots on the Sun’s Earth-facing hemisphere. As I have done every month for the entire thirteen years I have been doing this website, I have posted that updated graph below, adding to it some extra details to provide some context.

Though the sunspot count in July was slightly less than the very high numbers in June (the highest seen in more than two decades), the decline was almost inconsequential. Except for June’s activity, the activity in July was still the highest sunspot count in a month since September 2002, when the Sun was just beginning its ramp down after its solar maximum that reached its peak in late 2001. From that time until the last two months, the Sun had been in a very prolonged quiet period, with two solar minimums that were overly long and a single solar maximum that was very weak with a extended double peak lasting almost four years.
» Read more

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The wind-scoured dusty and cratered dry tropics of Mars

1:16 pm

The wind-scoured dusty and cratered dry tropics of Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 2, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows one small area in Martian equatorial regions where the main features are a dusty plain interspersed with craters, not entirely dissimilar to the Moon .

In the picture the northwest-to-southeast orientation of ridge-lines, plus the position of divots with their steep and deep end all on the northwest side, all suggest the prevailing winds here blow in the same direction, from the northwest to the southeast.

We are looking at a very ancient terrain. Many of these craters likely date from the early bombardment period of the solar system, just after the planets had formed but there was still a lot of objects around crashing into them.
» Read more

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Eruption on comet results in its tail splitting as it brightens by 100x

9:28 am

On July 20, 2023 the Comet 12P/Pons-Brooks suddenly erupted for the first time in almost seven decades, making it a hundred times brighter than normal while splitting its tail in two.

As of July 26, the comet’s coma had grown to around 143,000 miles (230,000 kilometers) across, or more than 7,000 times wider than its nucleus, which has an estimated diameter of around 18.6 miles (30 km), Richard Miles, an astronomer with the British Astronomical Association who studies cryovolcanic comets, told Live Science in an email.

But interestingly, an irregularity in the shape of the expanded coma makes the comet look as though it has sprouted horns. Other experts have also likened the deformed comet to the Millennium Falcon, one of the iconic spaceships from Star Wars, Spaceweather.com reported.

It is believed the tail’s shape is the result of the shape of the comet’s nucleus, which probably had a solid ridge acting as a barrier to material at that point.

The comet, which orbits the Sun every 71 years, will make its closest approach to Earth in the spring of 2024, when it will likely be visible to the naked eye.

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Monitoring the gullies on Mars for changes

12:54 pm

Monitoring the gullies on Mars
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on March 24, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) as part of a long term monitoring program of the many Martian gullies scientists have found above 30 degrees north latitude on a variety of slopes.

Martian gullies are small, incised networks of narrow channels and their associated downslope sediment deposits, found on the planet of Mars. They are named for their resemblance to terrestrial gullies. First discovered on images from Mars Global Surveyor, they occur on steep slopes, especially on the walls of craters. Usually, each gully has a dendritic alcove at its head, a fan-shaped apron at its base, and a single thread of incised channel linking the two, giving the whole gully an hourglass shape. They are estimated to be relatively young because they have few, if any craters.

…Most gullies occur 30 degrees poleward in each hemisphere, with greater numbers in the southern hemisphere. Some studies have found that gullies occur on slopes that face all directions; others have found that the greater number of gullies are found on poleward facing slopes, especially from 30° to 44° S. Although thousands have been found, they appear to be restricted to only certain areas of the planet. In the northern hemisphere, they have been found in Arcadia Planitia, Tempe Terra, Acidalia Planitia, and Utopia Planitia. In the south, high concentrations are found on the northern edge of Argyre basin, in northern Noachis Terra, and along the walls of the Hellas outflow channels.

Orbital data has identified almost 5,000 gullies on Mars. Based on their shape and the Martian climate, scientists generally think these gullies were formed by some form of water flow, possibly coming from an underground aquifer at their top.
» Read more

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Scientists increasingly put politics over uncertainty in their research papers

10:35 am

The modern scientific method
The modern scientific method

The death of uncertainty in science: According to a paper published this week in the peer-review journal Science, scientists in recent years are increasingly abandoning uncertainty in their research papers and are instead more willing to make claims of absolute certainty without hesitation or even proof.

If this trend holds across the scientific literature, it suggests a worrisome rise of unreliable, exaggerated claims, some observers say. Hedging and avoiding overconfidence “are vital to communicating what one’s data can actually say and what it merely implies,” says Melissa Wheeler, a social psychologist at the Swinburne University of Technology who was not involved in the study. “If academic writing becomes more about the rhetoric … it will become more difficult for readers to decipher what is groundbreaking and truly novel.”

The new analysis, one of the largest of its kind, examined more than 2600 research articles published from 1997 to 2021 in Science, which the team chose because it publishes articles from multiple disciplines. (Science’s news team is independent from the editorial side.) The team searched the papers for about 50 terms such as “could,” “appear to,” “approximately,” and “seem.” The frequency of these hedging words dropped from 115.8 instances per 10,000 words in 1997 to 67.42 per 10,000 words in 2021.

Those numbers represent a 40% decline, a trend that has been clear for decades, first becoming obvious in the climate field. » Read more

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Euclid’s first images look good

9:19 am

Scientists have determined that the first test images from the two cameras on the recently launched orbiting Euclid space telescope are sharp and as expected.

Both VIS and NISP provided these unprocessed raw images. Compared to commercial products, the cameras are immensely more complex. VIS comprises 36 individual CCDs with a total of 609 megapixels and produces high-resolution images of billions of galaxies in visible light. This is how astronomers determine their shape. The first images already give an impression of the abundance that the data will provide.

NISP’s detector consists of 16 chips with a total of 64 megapixels. It operates in the near-infrared at wavelengths between 1 and 2 microns. In addition, NISP serves as a spectrograph, which splits the light of the captured objects similar to a rainbow and allows for a finer analysis. These data will allow the mapping of the three-dimensional distribution of galaxies.

Knowing that 3D distribution will allow scientists to better determine the nature of both dark energy (related to the acceleration of the universe’s expansion) and dark matter (related to an undiscovered mass that affects the formation and shape of galaxies).

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Meandering ridge exiting glacier on Mars

11:34 am

Overview map

Meandering ridge exiting glacier on Mars
Click for original image.

Today’s cool image illustrates the complex explanations scientists sometimes have to come up with explain the strange geology seen on Mars. The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 30, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label as a whitish “ridged flow-like feature” that appears to exit out of the massive hill to the west.

The white dot on the overview map above as well as in the inset marks this location, smack dab inside the 2,000-mile-long strip of glacier country in the Martian northern mid-latitudes. As you can see from the inset, that massive hill is actual the foot of a large apron of material, likely ice-infused, that has sagged down from the large 5,400-foot high mesa to the west.

The white material is likely what the scientists call an inverted river. Once it was a channel in which either water or ice flowed. With time the weight of that material compacted the riverbed so that it was denser than the surrounding terrain, much of which was likely soft anyway because of a high ice content. When that surrounding terrain eroded away, the riverbed resisted that erosion, and instead became the raised ridge we now see.

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Trial operations begin for China’s new radio array for observing the Sun

10:02 am

Engineers have begun trial operations for a almost two-mile diameter antenna array in China designed to observe the Sun.

The Daocheng Solar Radio Telescope (DSRT) consists of 313 dishes, each with a diameter of 19.7 feet (6 meters), forming a circle with a circumference of 1.95 miles (3.14 kilometers). A 328-feet-high (100 m) calibration tower stands in the center of the ring. The array has undergone half a year of debugging and testing, demonstrating the capability to consistently and reliably monitor solar activity with high precision. Trial operations officially started July 14, according to CCTV News.

This design is a variation of the VLA radio antenna in New Mexico, which has 28 antennas arranged not in a circle but in a Y-configuration that can be extended or shortened. That additional capability is probably why VLA is focused on astronomical observations, not just the Sun.

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Contact lost with Voyager 2, hopefully temporarily

9:28 am

New but planned commands to Voyager 2, presently flying beyond the solar system, caused the spacecraft to point its antenna incorrectly so that communications with Earth have been lost.

A series of planned commands sent to NASA’s Voyager 2 spacecraft on July 21 inadvertently caused the antenna to point 2 degrees away from Earth. As a result, Voyager 2 is currently unable to receive commands or transmit data back to Earth.

Voyager 2 is located almost 12.4 billion miles (19.9 billion kilometers) from Earth and this change has interrupted communication between Voyager 2 and the ground antennas of the Deep Space Network (DSN). Data being sent by the spacecraft is no longer reaching the DSN, and the spacecraft is not receiving commands from ground controllers.

The spacecraft is also programmed to periodically reset its orientation so that its antenna points to Earth, with the next reset scheduled for October 15th. Engineers hope that at that point contact will be recovered.

If not, this incident will mark the end of the mission, which launched in 1977 and has been functioning for 46 years as it has made close fly-bys of Jupiter, Saturn, Uranus, and Neptune, and then eventually entering interstellar space.

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Endless dunes in the dry Martian equatorial region

1:01 pm

Endless dunes in the dry Martian equatorial region
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and sharpened to post here, was taken on May 14, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small section of a vast dune field, 50 miles square, that sits about 225 miles south of the southern foothills of Mars’ biggest volcano, Olympus Mons.

The dunes are probably less than 20 feet high, with that one small hill only slightly higher. Their similar orientation, which extends across the entire 50-mile-square dune field, indicates the direction of the prevailing winds, which I think (but will not swear to it) is from the southeast to the northwest, which also happens to also follow the grade downhill to the northwest.

It is also possible that wind direction is the reverse, and goes uphill to the southwest.
» Read more

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Scientists think they have finally discovered what makes the Sun’s corona so hot

10:31 am

Using data from Europe’s Solar Orbiter spacecraft, scientists now think they have finally pinpointed the process that causes the Sun’s corona — its atmosphere — to be many times hotter than its surface.

For decades, scientists have been struggling to explain why temperatures in the sun’s outer atmosphere, the corona, reach mind-boggling temperatures of over 1.8 million degrees Fahrenheit (one million degrees Celsius). The sun’s surface has only about 10,000 degrees F (6,000 degrees C), and with the corona farther away from the source of the heat inside the star, the outer atmosphere should, in fact, be cooler.

New observations made by the Europe-led Solar Orbiter spacecraft have now provided hints to what might be behind this mysterious heating. Using images taken by the spacecraft’s Extreme Ultraviolet Imager (EUI), a camera that detects the high-energy extreme ultraviolet light emitted by the sun, scientists have discovered small-scale fast-moving magnetic waves that whirl on the sun’s surface. These fast-oscillating waves produce so much energy, according to latest calculations, that they could explain the coronal heating.

You can read the paper here [pdf]. The results have not yet been confirmed, but if so it will solve one of the space age’s oldest scientific mysteries.

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Astronomers chemically map a significant portion of the Milky Way

10:19 am

The chemistry of the Milky Way's nearby spiral arms
Red indicates areas with lots of heavier elements, blue indicates
areas dominated by hydrogen and helium. Click for original image.

Astronomers have now used today’s modern survey telescopes — on Earth and in space — to map the chemistry of a large portion of the Milky Way’s nearby spiral arms, revealing that the arms themselves are rich in heavier elements, indicating greater age and the right materials to produce new stars and solar systems like our own.

If the Milky Way’s spiral arms trigger star births as predicted, then they should be marked by young stars, aka metal-rich stars. Conversely, spaces between the arms should be marked by metal-poor stars.

To confirm this theory, as well as create his overall map of metalicity, Hawkins first looked at our solar system’s galactic backyard, which include stars about 32,000 light years from the sun. In cosmic terms, that represents our stellar neighborhood’s immediate vicinity.

Taking the resultant map, the researcher compared it to others of the same area of the Milky Way created by different techniques, finding that the positions of the spiral arms lined up. And, because he used metalicity to chart the spiral arms, hitherto unseen regions of the Milky Way’s spiral arms showed up in Hawkins’ map. “A big takeaway is that the spiral arms are indeed richer in metals,” Hawkins explained. “This illustrates the value of chemical cartography in identifying the Milky Way’s structure and formation. It has the potential to fully transform our view of the Galaxy.”

You can read the science paper here [pdf]. Based on this initial mapping effort, it appears that it will not be long before a large percentage of our own galaxy will be mapped in this manner.

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Juno’s next fly-by of Io coming on July 30

9:54 am

Io as seen by Juno
An image of Io from the March fly-by

The Juno science team is gearing up for the spacecraft’s next fly-by of the Jupiter moon Io, scheduled for July 30, 2023.

When NASA’s Juno mission flies by Jupiter’s fiery moon Io on Sunday, July 30, the spacecraft will be making its closest approach yet, coming within 13,700 miles (22,000 kilometers) of it. Data collected by the Italian-built JIRAM (Jovian InfraRed Auroral Mapper) and other science instruments is expected to provide a wealth of information on the hundreds of erupting volcanoes pouring out molten lava and sulfurous gases all over the volcano-festooned moon.

The image to the right was taken from 33,000 miles during the March fly-by, almost three times farther away. The dark spots are volcanoes, and some showed significant change from earlier images.

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OSIRIS-REx completes last major mid-course correction before sending its sample capsule back to Earth

9:38 am

OSIRIS-REx yesterday completed a 63 second engine burn, successfully aiming the spacecraft so that its September 24th drop off of its sample capsule will hit the Earth as planned.

Preliminary tracking data indicates OSIRIS-REx changed its velocity, which includes speed and direction, by 1.3 miles, or 2 kilometers, per hour. It’s a tiny but critical shift; without course adjustments like this one the spacecraft would not get close enough to Earth on Sept. 24 to drop off its sample of asteroid Bennu. The spacecraft is currently 24 million miles, or 38.6 million kilometers, from Earth, traveling at about 22,000 miles, or about 35,000 kilometers, per hour.

In the two weeks prior to that drop-off the spacecraft will do two more short burns to refine its aim so that the sample capsule will land precisely as planned on the Defense Department’s Utah Test and Training Range near Salt Lake City.

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Giant glaciers in the northern Martian mid-latitudes

12:57 pm

Overview map

Giant glaciers in the northern Martian mid-latitudes
Click for original image.

It is time for two cool images! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and is one of two glaciers imaged by MRO in May that are among a whole series of glaciers flowing down the south wall of the same mesa.

The red dot in the inset and on the overview map above marks the location of the picture to the right. The white dot marks the location of the May 27, 2023 picture, which can be seen here.

The unnamed 10,000-foot-high mesa from which these glaciers flow, located in the middle of the 2,000-mile-long northern mid-latitude strip I dub glacier glacier country, is about 41 miles long and 18 miles wide at its widest point. The glacier to the right falls about 6,000 feet in about four miles, making the grade steep, ranging from 15 to 23 degrees. That steepness explains the split in the glacier, as it flowed around a huge piece of higher bedrock in the middle of this descending hollow.

Both images provide further evidence of the dominance of glaciers in this mid-latitude region. While the glaciers are all covered with dust and debris to protect the ice, and are also thought at present to all be inactive, they also all suggest a very dynamic Martian geological and climate history, one that will likely come alive again as the planet’s rotational tilt naturally shifts back and forth from its present 25 degree tilt to 11 to 60 degrees.

The glaciers also show us again that Mars is not a dry desert, but above 30 degrees latitude it is an icy desert much like Antarctica. Colonists will have no trouble finding water.

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Optical image of accretion disk around baby star, taken by ground-based VLT

10:59 am

Stellar accretion disk
Click for original image.

Scientists today released an optical image of the accretion disk that surrounds a baby star about 5,000 light years away, taken by ground-based Very Large Telescope (VLT) in Chile and enhanced by data from the Atacama Large Millimeter/submillimeter Array (ALMA), also in Chile.

That image, reduced to post here, is to the right. The bright blue spot in the center is the main star, with the smaller dot to the lower left a companion star. From the press release:

The VLT observations probe the surface of the dusty material around the star, while ALMA can peer deeper into its structure. “With ALMA, it became apparent that the spiral arms are undergoing fragmentation, resulting in the formation of clumps with masses akin to those of planets,” says Zurlo.

Astronomers believe that giant planets form either by ‘core accretion’, when dust grains come together, or by ‘gravitational instability’, when large fragments of the material around a star contract and collapse. While researchers have previously found evidence for the first of these scenarios, support for the latter has been scant.

This data suggests that the latter is being observed, the first time gravitational instability has been identified as it is happening. You can read the scientist’s research paper here [pdf].

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Infrared Webb image of a binary baby star system and its surrounding jets and nebula

10:47 am

Webb infrared image of HH 46/47
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Cool image time! The infrared picture to the right, cropped, reduced, and sharpened to post here, was taken by the Webb Space Telescope of the jets and nebula of the Herbig–Haro object dubbed HH 46/47, thought to contain a pair of baby stars under formation.

The most striking details are the two-sided lobes that fan out from the actively forming central stars, represented in fiery orange. Much of this material was shot out from those stars as they repeatedly ingest and eject the gas and dust that immediately surround them over thousands of years.

When material from more recent ejections runs into older material, it changes the shape of these lobes. This activity is like a large fountain being turned on and off in rapid, but random succession, leading to billowing patterns in the pool below it. Some jets send out more material and others launch at faster speeds. Why? It’s likely related to how much material fell onto the stars at a particular point in time.­­­

The stars’ more recent ejections appear in a thread-like blue. They run just below the red horizontal diffraction spike at 2 o’clock. Along the right side, these ejections make clearer wavy patterns. They are disconnected at points, and end in a remarkable uneven light purple circle in the thickest orange area. Lighter blue, curly lines also emerge on the left, near the central stars, but are sometimes overshadowed by the bright red diffraction spike.

To see optical images of HH 46/47 as well as some further background, go here. It is one of the most studied HH objects, which is why it was given priority in Webb’s early observation schedule.

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Swirling layers in the basement of Mars

11:28 am

Swirling layers in the basement of Mars
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Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on March 31, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

In labeling this picture the science team focused on the many layers visible in these swirls, all suggesting a series of cyclical events, each laying down a new layer over many eons.

What caused the swirls? Looking at the lower right quadrant it appears that they were glacial, with the flow to the northwest but with each glacial layer smaller and not reaching as far.

This theory falls apart however at the curved depression, which instead suggests the swirl was traveling along a meandering canyon, going from the lower left to the upper right. If so, the curved depression is even more baffling. If ice it could have sublimated away, but its sharp edges suggest this isn’t ice but maybe a lava flow.
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