Tag: science

Scientists release first image from Hubble in one-gyro mode

9:29 am

First Hubble image in one-gyro mode
Click for original image.

The Hubble science team today released the first image from the Hubble Space Telescope produced in its new one-gyro mode.

That image it so the right, cropped, reduced, and sharpened to post here, and shows NGC 1546, a nearby galaxy in the constellation Dorado about 52 million light years away. The inset shows at full resolution the small red galaxy near the top, to give some sense of the telescope’s capabilities in this one-gyro mode.

The details astonish me, and prove my pessimism about this new mode to have been wrong. I expected future images to be more fuzzy, with Hubble’s ability to take sharp images largely limited. The resolution here is excellent, and bodes well for future science observations.

Nonetheless, the telescope is still working under major limitations:

Although one-gyro mode is an excellent way to keep Hubble science operations going, it does have limitations, which include a small decrease in efficiency (roughly 12 percent) due to the added time required to slew and lock the telescope onto a science target.

As previously noted, prior to the use of the fine guidance sensors, fixed head star trackers position Hubble’s pointing closer to the target. If Earth or the moon block two of the fixed head star trackers’ fields of view, Hubble must move further along in its orbit until the star trackers can see the sky and its stars again. This process encroaches upon science observation time. Second, the additional time the fine guidance sensors take to further search for the guide stars adds to the total time the sensors use to complete the acquisition.

Third, in one-gyro mode Hubble has some restrictions on the science it can do. For example, Hubble cannot track moving objects that are closer to Earth than the orbit of Mars. Their motion is too fast to track without the full complement of gyros. Additionally, the reduced area of sky that Hubble can point to at any given time also reduces its flexibility to see transient events or targets of opportunity like an exploding star or an impact on Jupiter.

When combined, these factors may yield a decrease in productivity of roughly 20 to 25 percent from the typical observing program conducted in the past using all three gyros.

It really is time for the astronomical community to get its act together and begin work on developing and launching more large optical telescopes into space. Hubble has shown us the potential of in-space optical astronomy. That astronomers have not flocked in the last three decades to build more such telescopes is puzzling beyond belief.

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Massive Martian landslides

3:09 pm

Massive Martian landslides
For original images go here and here.

Overview map

Today’s two cool images above provide a nice sense of the massive nature of many Martian landslides. Scientists often call this kind of slide “mass wasting,” because rather than it occurring because a single rock propagates a larger flow of rocks as it starts rolling downhill, this slide occurs because a large section of the hillside suddenly breaks free and moves downward as a unit, carving a path as it goes.

Mars has a lot of these kinds of slides, likely caused partly by its lower gravity, 39% that of Earth’s.

The overview map to the right marks the location of both slides by their numbers. Number one took place on the eastern interior rim of a 56-mile-wide and 7,000-foot-deep unnamed crater the dry tropics of Mars. The slide dropped about 3,000 feet, beginning about halfway down from the top of the rim and not quite reaching the crater floor. The picture was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on March 31, 2024.

Number two occurred on the western interior rim of a 32-mile-wide and 6,500-foot-deep unnamed crater in the mid-latitudes where near-surface ice and glacial features are often found. In this case the slide fell downward about 3,500 feet. The picture was taken by MRO’s high resolution camera on March 14, 2024.

Despite the different latitudes and thus different climates and geological settings, both landslides look similar. It is possible they occurred under similar conditions, but at very different times. Or it is also possible that the Mars gravity and general environment promotes these mass wasting events everywhere.

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Surprise! Scientists discover that eating cheese makes you happier in old age!

9:52 am

Science discovers the obvious: A computer analysis of 2.3 million people in Europe has found that eating cheese helped make them healthier and happier as they aged.

A mediation analysis identified 33 factors that mediate “between the well-being spectrum and the aging-GIP” – essentially, statistically, the disease, behaviors and lifestyle choices that significantly reduce the healthy aging score. Key ones included TV watching, smoking, medication use, heart failure, attention-deficit hyperactivity disorder (ADHD), stroke, coronary atherosclerosis and ischemic heart disease.

Cheese, on the other hand, swung the pendulum the other way in both its impact on the well-being spectrum and aging-GIP. One of five key lifestyle mediators the data testing identified, it had a 3.67% positive impact on those healthy aging factors (whereas, for example, higher fruit intake had a 1.96% positive result and too much TV time, an indication of a more sedentary lifestyle, had a 7.39% negative impact on the score for both indicators).

While interesting, this research is generally junk. The number of uncertainties and assumptions are so large that no one should take any of these positive and negative scores very seriously. Furthermore, the study basically discovers something that is patently obvious from the beginning: If you are active and eat well, you will be healthier in old age. If you are a couch potato who smokes, you will likely be sicker in old age.

Why cheese (and fruit) should improve these scores is intriguing, but simply suggests that the study is not very useful. The intriguing (and amusing) nature of these results guarantees however that it will blasted by every mainstream news source in the coming days, with little mention of the weakness of the research.

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Once again, the first known binary of two supermassive black holes flares as predicted

9:37 am

The predicted orbit of OJ287

Using a variety of space telescopes astronomers have successfully predicted and then observed a major flare that occurred on November 12, 2021 from OJ287, the first known binary of two supermassive black holes located 3.5 billion light years away at the center of a very active galaxy dubbed a blazar.

On Nov. 12, 2021, TESS detected OJ 287 brightening by about two magnitudes for about 12 hours, as it released as much energy in that short burst as 100 average galaxies would release in the same time. This flare was attributed to a jet from the second black hole; observations from the other telescopes supported that result as well, with Fermi in particular detecting a significant outburst of gamma rays.

The figure to the right comes from the published paper [pdf], and shows the orbit of the smaller supermassive black hole — weighing 150 million solar masses — as it circled the larger central supermassive black hole — weighing 18 billion solar masses — from 2000 to 2021.

This was not the first time such a flare from OJ287 had been predicted and observed. Astronomers also did it in 2019. These observations now strongly confirm the predicted orbit of the small black hole, as shown in the figure.

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The insane mountain slopes of Mars’ deep canyons

3:40 pm

Overview map

The insane mountain slopes of Mars' deep canyons
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 25, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists label this layered deposits, but that hardly describes what we are looking at. This slope, as shown in the overview map above, is the north flank of the central ridgeline inside the giant enclosed canyon depression dubbed Hebes Chasma, located just north of the main canyon of Valles Marineris, the largest known canyon in the solar system.

From floor to peak the ridge is around 16,000 feet high. Yet, its peak sits more than 6,000 feet below the plateau that surrounds Hebes. In this one picture the drop from high to low is only 5,700 feet, with thousands of feet of cliff unseen below and above.

Yet every single foot of these gigantic cliffs is layered. Based on close-up data obtained by Curiosity on the slopes of Mount Sharp in Gale Crater on the other side of the planet, the layers we can see here only represent the most coarse sedimentary boundaries. Within these layers are likely thousands upon thousands of thin additional layers, each likely representing some cyclical climate proces on Mars, even down to individual years.

Note too that the lower slopes in this picture (near the top) suggest some form of erosion flowing downhill. What caused that erosion process however remains unknown. It could have been liquid water, or glaciers, or some other process unique to Mars that we still haven’t uncovered.

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Lunar Reconnaissance Orbiter snaps picture of Chang’e-6 on far side of the Moon

10:23 am

Chang'e-6's landing site
Click for original image of Chang’e-6 on the Moon

The science team running Lunar Reconnaissance Orbiter (LRO) have now released an image of China’s Chang’e-6 lander on far side of the Moon, taken on June 7, 2024 one week after the spacecraft touched down.

Chang’e 6 landed on 1 June, 2024, and when LRO passed over the landing site almost a week later, it acquired an image showing the Chang’e 6 lander on the rim of an eroded ~50 meter diameter crater.

The LROC team computed the landing site coordinates as 41.6385°S, 206.0148°E, at -5256 meters elevation relative to the average lunar surface, with an estimated horizontal accuracy of plus-or-minus 30 meters.

The overview map to the right, showing the entire far side of the Moon, shows that picture as the inset in the lower left, cropped to post here. The black and white dot in the center is Chang’e-6’s lander, with the surrounding brightened ground showing the blast area produced by the engines during touchdown.

According to the LRO press release, the large dark area that surrounds the lander — as seen in the wider inset in the upper right — is a “basaltic mare deposit” — similar to the vast dark frozen lava seas evident to our own eyes on the near side of the Moon.

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Webb produces false color infrared image of the Crab Nebula

9:30 am

The Crab Nebula as in infrared by Webb
Click for original image.

The false-color infrared picture to the right, reduced and sharpened to post here, was taken by the Webb Space Telescope of the Crab Nebula, located 6,500 light years away and created when a star went supernova in 1054 AD, in order to better understand its make-up and origins. From the caption:

The supernova remnant is comprised of several different components, including doubly ionized sulfur (represented in green), warm dust (magenta), and synchrotron emission (blue). Yellow-white mottled filaments within the Crab’s interior represent areas where dust and doubly ionized sulfur coincide.

The spectroscopic data from this infrared observation has in fact increased the puzzle of the Crab’s origin. Previously the data suggested the supernova that caused it was one type of supernova. This data now suggests it could have been a different type, without precluding the possibility of the first.

“Now the Webb data widen the possible interpretations,” said Tea Temim, lead author of the study at Princeton University in New Jersey. “The composition of the gas no longer requires an electron-capture explosion, but could also be explained by a weak iron core-collapse supernova.”

You can read the published science paper here [pdf].

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Archaeologists discover 35 glass jars at Mount Vernon from 1700s, most containing edible preserved fruits

11:31 am

During an on-going renovation at George Washington’s Mount Vernon home, archaeologists have discovered 35 glass jars from the 1700s, with most containing preserved cherries and berries that appear completely edible.

Of the 35 bottles, 29 are intact and contain perfectly preserved cherries and berries, likely gooseberries or currants. The contents of each bottle have been carefully extracted, are under refrigeration at Mount Vernon, and will undergo scientific analysis. The bottles are slowly drying in the Mount Vernon archaeology lab and will be sent off-site for conservation.

Only a small quantity of the preserved fruits has been analyzed, with the following results:

  • 54 cherry pits and 23 stems have been identified thus far, suggesting that the bottles were likely full of cherries before bottling. Cherry pulp is also present.
  • Microscopy suggests that the cherries may have been harvested by snipping from trees with shears. The stems were neatly cut and purposefully left attached to the fruit before bottling.
  • The cherries likely are of a tart variety, which has a more acidic composition that may have aided in preservation.
  • The cherries are likely candidates for DNA extraction, which could be compared against a database of heirloom varieties to determine the precise species.
  • The pits are undergoing an examination to determine if any are viable for germination.

The last point is most fascinating. Imagine if a new cherry tree could be grown from a pit that was likely picked when George Washington was alive.

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Perseverance looks back at downstream Neretva Vallis

9:58 am

Perseverance looks backwards
Click for full resolution version. Highly recommended!

Cool image time! The panorama above was released today by the science team of the Mars rover Perseverance, created from 56 pictures taken by the rover’s high resolution camera. It looks east, downstream into Neretva Vallis, what is believed to be the ancient riverbed that produced the delta that now exists inside Jezero Crater.

The yellow lines in the overview map below indicate the approximate area shown by the panorama. The blue dot marks where Perseverance was located when it took these pictures on May 17, 2024.

Make sure you look at the full resolution image. Neretva Vallis, the depression in the center of the panorama, is about a quarter-mile wide. The green dot on the map marks Ingenuity’s final landing spot. Though the helicopter is somewhere inside that panorama, it does not appear to be visible as it lies on the far side of one of those dunes.

It is also possible that Ingenuity is visible, but is only a tiny dark dot that makes it hard to identify. In reviewing the high resolution image closely, there is one dot that could be Ingenuity.

Overview map
Click for interactive map.

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Study: Dust removal at Jezero 9x greater than InSight landing area

11:41 am

Figure 2 from the paper
Figure 2 from the paper. Click for original.

Using data from the Mars rover Perseverance, scientists have concluded that dust removal rate in Jezero crater is almost ten times greater than where InSight landed in western Elysium Planitia.

The graph, figure 2 from their paper, illustrates that differents starkly. From their abstract:

Dust removal is almost 10 times larger than at InSight’s location: projections indicate that surfaces at Jezero will be periodically partially cleaned. The estimations of the effect of the accumulated dust as a function of time are encouraging for solar-powered missions to regions with similar amounts of dust lifting, which might be determined from orbital data on where dust storms originate, dust devils or their tracks are found, or seasonal albedo changes are noted.

In other words, it might be practical to send solar powered rovers to different places on Mars, if first research was done to see if the conditions there would regularly clear dust from those panels.

This research confirms what had been implied by the different experiences of landers/rovers in different places on Mars. InSight landed near the equator in a region south of the giant shield volcano Elysium Mons. It only survived four years, with steadily lower energy levels, because no wind or dust devil ever cleared the accumulating dust on its solar panels. Spirit meanwhile landed about 1,500 miles southwest of InSight, yet its power levels were still healthy after more than five years of operations, when those operations ended because the rover could no longer move. The rover Opportunity meanwhile on the other side of the planet lasted more than fourteen years. Both rovers relied on solar power, like InSight, but their solar panels kept getting cleared of dust by wind and dust devils.

It is unclear if this wind research has been done for Europe’s Franklin rover, presently scheduled to land in Oxia Planum in 2028. Franklin will rely on solar panels, and though its nominal mission on the surface is only supposed to last seven months, it is always assumed it will continue until the rover fails.

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Perseverance looks up at the rim of Jezero Crater

1:01 pm

Panorama on June 10, 2024 by Perseverance
Click for full resolution. For original images, go here, here, here, and here.

Overview map
Click for interactive map.

Cool image time. The panorama above was created from four pictures taken on June 10, 2024 by the left navigation camera on the Mars rover Perseverance (captions found here, here, here, and here). It looks north at the nearest hill that forms the north part of the rim of Jezero Crater.

The overview map to the right provides context. The blue dot marks Perseverance’s present location, when it took these pictures. The yellow lines indicate the approximate area covered by the panorama. The red dotted line marks the rover’s planned route, while the white dotted line the route it has actually taken.

Because the rover is now at the base of this hill, it can no longer see the top of the crater’s rim. What it sees instead is the barren foothills of that rim, covered with dust, dunes, and many broken rocks.

As I have noted numerous times, the utter lack of life marks this as a truly alien landscape, compared to Earth. Nowhere on our home planet would you see terrain this empty of life. While NASA likes to claim that Perseverance’s main mission is the search for life on Mars, that claim is always a lie. It is very unlikely any life is going to be found here by Perseverance, and if that was its true scientific purpose it would never have been built nor launched.

What the scientists are doing is studying the alien geology of Mars, to try to understand how this utterly alien planet got to be the way it is now. Such knowledge is critical for the future explorers of space, as it will make it easier for them to understand the alien landscapes they will find elsewhere, within the solar system and eventually in other solar systems far beyond.

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Curiosity sees evidence of solar storm hitting Mars

12:11 pm

Charged particles from solar storm
Click to see original three-frame movie.

Cool image time! The picture to the right is a screen capture from a three-frame movie created from photos taken by one of the navigation cameras on the Mars rover Curiosity. The white streak and other smaller streaks were created by charged particles hitting the camera’s CCD detector on May 20, 2024, from a solar storm caused by the strong solar flares presently being pumped out by the Sun.

The mission regularly captures videos to try and catch dust devils, or dust-bearing whirlwinds. While none were spotted in this particular sequence of images, engineers did see streaks and specks – visual artifacts created when charged particles from the Sun hit the camera’s image detector. The particles do not damage the detector.

The images in this sequence appear grainy because navigation-camera images are processed to highlight changes in the landscape from frame to frame. When there isn’t much change — in this case, the rover was parked — more noise appears in the image.

Curiosity’s Radiation Assessment Detector (RAD) measured a sharp increase in radiation at this time – the biggest radiation surge the mission has seen since landing in 2012.

The view of this picture is to the south, looking towards the top of Mount Sharp, though that peak, more than 25 miles away, is not visible because the mountain’s lower flanks are in the way. A second movie showing similar charged particle streaks was taken looking south, with the rim of Gale Crater barely visible 20-30 miles away.

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