Tag: science

A giant elliptical galaxy

3:14 pm

A giant elliptical galaxy
Click for full image.

Cool image time! The image to the right, reduced to post here, was taken by the Hubble Space Telescope of the giant elliptical galaxy NGC 474.

Located some 100 million light-years from Earth, NGC 474 spans about 250,000 light-years across – that’s 2.5 times larger than our own Milky Way galaxy! Along with its enormous size, NGC 474 has a series of complex layered shells that surround its spherical-shaped core. The cause of these shells is unknown, but astronomers theorize that they may be the aftereffects of the giant galaxy absorbing one or more smaller galaxies. In the same way a pebble creates ripples on a pond when dropped into the water, the absorbed galaxy creates waves that form the shells.

About 10% of elliptical galaxies have shell structures, but unlike the majority of elliptical galaxies, which are associated with galaxy clusters, shelled ellipticals usually lie in relatively empty space. It may be that they’ve cannibalized their neighbors.

NGC 474 is no exception, also located in a relatively empty region of space.

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The tuffy ground in the foothills of Mount Sharp

11:50 am

Shelfstone on Mars?
Click for original image.

Cool image time! The photo to the right, reduced and enhanced to post here, was taken on May 13, 2022 by the high resolution camera on the rover Curiosity, looking down at some of the unusual features on the ground near the rover.

The lighter circular feature in the center is not natural, but created by Curiosity’s Dust Removal Tool (DRT). As explained on May 16th on the science team’s blog:

When that dust settles on rocks, it can partially mask the chemistry and surface texture of these rocks from APXS and MAHLI in particular [two other Curiosity instruments]. Brushing rock surfaces with the DRT is not always possible, but it does improve scientific assessments of these surfaces.

What attracted me to this photo was the tuff-like look of that uplifted flat rock. It looks just like many surfaces one sees in a cave, where the surface gets covered with calcite flowstone or popcorn, due to either water flow or condensation and then evaporation of calcite-saturated water on the surface. In this case the cave formation this flat rock most resembles visually is shelfstone, though the formation process and chemistry was certainly different. It does suggest strongly however that some form of water process occurred here.

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InSight likely to shut down by the end of summer

9:33 am

Martian quake map as seen by InSight
Martian quake map as seen by InSight, adapted from this 2021
presentation [pdf]

According to the InSight science team, the Mars lander and its seismometer will likely shut down operations by the end of the summer due to lack of power.

“Towards the end of summer of ’22, we anticipate our seismometer will be turned off, not because we want to turn it off but unfortunately, we don’t have the energy to run it,” Garcia said. She said the team will use it intermittently after that as long as power is available, but by the end of the year the spacecraft is expected to fall silent.

The intermittent readings of the seismometer will be of extremely limited use, as it will then be pure luck whether it detects a quake, and any detection will not provide the true rate of quakes on Mars.

The loss of power is due to dust on the solar panels. The team had hoped a dust devil would come by periodically to blow the panels clean, as happened routinely with the Spirit and Opportunity rovers, but InSight has not been so lucky.

It appears the safe mode that occurred shortly after InSight detected its largest Mars quake yet on May 10th was very temporary, though right now the seismometer is essentially the only instrument they have power to run.

Overall, this mission has a very spotty history. Its launch was delayed two years when the French attempt to build the seismometer failed. The delay cost NASA’s planetary program $150 million, at a minimum.

Then lander’s second of two main instruments, a German experiment to dig down 16 feet to insert a heat sensor into the ground, failed when its digging tool, dubbed the mole, was unable to penetrate the alien Martian soil.

Fortunately, InSight’s prime instrument, the seismometer (finally completed by JPL) worked, giving us a first look into the structure of Mars’ interior as well as where earthquakes are found on its surface.

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Mahma Comparisons – Biggest volcano eruptions known

6:01 pm

An evening pause: I run this at 2x speed, but if you aren’t impatient enjoy it as it is. The size difference between the smallest and largest is quite daunting. Note too that this video only lists the known giant eruptions, explosive events that happened suddenly. It does not include some of the Earth’s largest long term volcanic events, such as the Deccan Traps, that happened repeatedly lasting millions of years that is thought to have possibly contributed to the extinction of the dinosaurs.

Hat tip Alton Blevins.

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Pointy rocks on Mars

11:45 am

Pointy rocks as seen by Curiosity
Click for full image.

Pointy rocks as seen by Perseverance
Click for full image.

We have two cool images today from both of America’s rovers on Mars, each of which illustrates the alien nature of the red planet.

First on the right, cropped, reduced, and sharpened to post here, is a close-up taken by Curiosity’s high resolution camera on May 14, 2022 of the rightmost jagged boulder in yesterday’s navigation panorama. The number of layers is astonishing, though hardly a unique phenomenon as seen by Curiosity in its travels. Each likely marks one of many climate and geological cycles, each laying down another unique stratum for a relatively short period of geological time. Some might be volcanic ash or lava layers. Some might be layers caused by climatic changes.

The ability of these thin layers to extend outward so much, almost like they were floating, illustrates the weak Martian gravity, as well as the thinness of its atmosphere. On Earth, if the wind and weather didn’t cause these flakes to break, the gravity would.

Second on the right, cropped and sharpened to post here, is a high resolution photo taken by Perseverance on May 15, 2022 of one of the cliff faces seen by the rover looking up into the delta in Jezero Crater. Here again we see many layers and jagged, pointy rocks, illustrating again the many cycles in the past that formed the delta as it flowed into the crater.

The smoothness on the surface of the leftmost pointy rock suggests that it has stood in this position for a long very time, allowing the wind of Mars’ very thin atmosphere to erode its rough surface.

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Curiosity climbs on!

11:47 am

Curiosity's view to the southeast, May 15, 2022 (Sol 3474)
Click for full resolution. Original images can be found here, here, and here.

Overview map
Click for interactive map.

Cool image time! The panorama above, created from three photos taken on May 15, 2022 by the right navigation camera on Curiosity, shows the rocky and hilly terrain directly ahead of the rover’s present course. In the far distance in the center left can faintly be seen the lower flanks of Mount Sharp itself. The dust in the winter air acts to partly obscure those distant slopes.

The overview map to the right shows us what we are looking at. The yellow lines are my rough guess at the terrain covered by the panorama. The blue dot marks Curiosity’s present position. The red dotted line the rover’s original planned route. The white arrows indicate one of the more interesting upcoming geological features, dubbed by scientists the “marker horizon,” a distinct layer found in many places on the flanks of Mount Sharp.

The green dot marks the approximate location of a recurring slope lineae, a place where the cliff is seasonally darkened by a streak that appears each spring and then fades.

The navigation panorama taken on May 15th also included four more shots covering terrain to the southwest, so what we see above is not necessarily where the rover is heading. The eventual goal is to get back to that red dotted line, but how the rover does so is apparently still being discussed by the science team. It appears they are trying to decide whether to head west again to reach Gediz Vallis Ridge, or instead cut south heading directly for Gediz Vallis.

Either way, that teethlike row of boulders in the near foreground is certainly impressive.

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Study: Russian astronauts on ISS have better techniques for protecting the brain

9:12 am

According to a study comparing the changes in the brain experienced during long term missions on ISS, it appears that the Russians have developed better protocols for preparing themselves for return to Earth that prevents the enlargement in one part of the brain seen in American astronauts.

From the link:

The study focused on 24 Americans, 13 Russians, and a small, unspecified number of astronauts from the ESA. The researchers collected MRI scans of the astronauts’ brains before and after they spent six months on the ISS (only 256 individuals have visited the space station).

After being in space, all the space travelers exhibited similar brain changes: cerebrospinal fluid buildup and reduced space between the brain and the surrounding membrane at the top of the head. The Americans, however, also had more enlargement in the regions of the brain that serve as a cleaning system during sleep, e.g. the perivascular space (PVS).

…The Russian astronauts did not exhibit enlarged PVS, suggesting there might be differences in protocol that are neuro-protective.

From the paper itself:

[Russian C]osmonauts undergo six lower body negative pressure (LBNP) sessions starting two weeks prior to landing, while NASA and ESA astronauts do not typically do it. LBNP induces caudal displacement of fluids from the upper body by placing the legs and pelvis in a semiairtight chamber with negative pressure.

An advanced resistive exercise device (ARED) is regularly used by space flyers to perform free weight exercises on the ISS, but the load and frequency of use are lower for [Russian] cosmonauts compared with NASA and ESA astronauts. Lifting heavy loads during resistive exercise is often accompanied by a brief Valsalva maneuver, inducing increased ICP and decreased cerebral blood flow and cerebrovascular transmural pressure, which can result in PVS fluid accumulation. Although the effects of LBNP and ARED on the brain during spaceflight are unknown, they could partly explain the different WM-PVS changes detected in astronauts and cosmonauts. We cannot exclude that other factors (e.g., diet) might play a role in this difference. Further studies are required to confirm these hypotheses.

Apparently two protocols are different that seem to help the Russians. First, the LBNP, developed by the Russians on their earlier space stations, is essentially a pair of pants that sucks fluids down to the legs, simulating the situation normally found on Earth, and thus reduces the fluids in the upper body sooner than landing. Second, doing exercises simulating lower weight loads apparently helps the Russians as well.

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Scientists grow plants in lunar soil brought by from Apollo missions

3:29 pm

In their first attempt, scientists have successfully grown plants in a small lunar soil sample brought by astronauts during the Apollo missions.

Researchers at the University of Florida had spent 11 years requesting permission from Nasa to borrow some of the lunar dust brought back by astronauts on the first manned Apollo 11 and Apollo 12 missions in 1969 and the Apollo 17 mission in 1972. Armstrong and Aldrin brought back 21.6kg of material including 50 rocks, samples of dust and two cores of rock after boring 13cm down into the Moon’s surface. They contained no water and no signs of life.

…The lunar samples are deemed to be of “incalculable historical and scientific significance”, so the scientists were given only 12 grams, just a few teaspoons’ full, to work with and had to design a miniature experiment.

The researchers used thimble-sized wells in a dish usually used for growing cells as miniature plant pots and filled each with about one gram of lunar soil. They moistened the soil with water and a solution of nutrients and added a small number of seeds from the Arabidopsis thaliana plant, a common flowering weed also known as mouse-ear or thale cress. [emphasis mine]

The plants grew, but were smaller and took longer to grow then plants on even the most extreme environments on Earth. The scientists also found that plants did better in buried lunar soil then the material on the surface that had been exposed to the harsh radiation of space, suggesting that plowing the soil before planting will enhance growth.

The highlighted words in the quote above illustrate the madness of NASA’s bureaucracy. These lunar samples were brought back so that scientists could study it, not so that it could be locked away in a vault forever never to be touched. To make this very intelligence experiment wait 11 years before getting permission is absurd.

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First radio image of event horizon of Milky Way’s central black hole

9:31 am

Sagittarius A*
Click for full image.

Using an array of eight radio telescopes worldwide, dubbed the Event Horizon Telescope because its purpose is to study black holes, scientists have obtained the first radio image of the event horizon of Sagittarius A* (pronounced “A-star”), the supermassive black hole at the center of the Milky Way.

The image to the right, reduced to post here, is that photo.

The image is a long-anticipated look at the massive object that sits at the very centre of our galaxy. Scientists had previously seen stars orbiting around something invisible, compact, and very massive at the centre of the Milky Way. This strongly suggested that this object — known as Sagittarius A* (Sgr A*, pronounced “sadge-ay-star”) — is a black hole, and today’s image provides the first direct visual evidence of it.

Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a “shadow”) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

This is the second supermassive black hole that the Event Horizon array has imaged. In 2019 it captured the central black hole of the galaxy M87, 55 million light years away. Like that first image, much of what we see here is created by computer, since the data from the eight radio telescopes needs to be massaged to create something as smooth and as complete as this.

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Mountains, Mesas, and Box Canyons on the floor of Valles Marineris

4:41 pm

Mountains, Mesas, and Box Canyons
Click for full image.

Overview map

Cool image time! The photo above, cropped, reduced, and rotated to post here, was taken on March 12, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small section of the floor of the giant 2,550-mile-long and 400-mile-wide Valles Marineris canyon on Mars. In fact, this section, as indicated by the black rectangle in the overview map below, is practically in the center of the canyon, at its widest point.

The geology here hints at several Martian processes. The mesas and closed canyons in the north are typical of chaos terrain, where it erosion appears to form along fault lines to create the random intersecting canyons. In other places on Mars, in the mid-latitudes, that erosion appears mostly formed by glacial activity. Here, in Valles Marineris at only 7 degrees north latitude, little ice had been expected.

However, this spot is also in the dead center of a region where orbital data from Europe’s Trace Gas Orbiter (TGO) suggests there is a surprisingly large underground reservoir of hydrogen, which is assumed could only exist if it was locked in water molecules.

In fact, at this spot the data suggests up to 40% of the near-surface material might be composed of water (by weight). If so, that underground reservoir of ice could be causing the erosion that is creating this massive chaos terrain.

Meanwhile, the light-colored mountain in the south is the westernmost nose of a 50-mile-long ridgeline coming down from the canyon’s rim, about 30,000 feet higher. Its dendritic nature, like the hollows that form in the mountains of wet regions on Earth, suggest rainfall and water flowing downhill, wearing away these hollows over eons.

Rain however is almost certainly not the cause. Instead, we could be seeing erosion from wind, or maybe dry ice snow that fell long ago when this region was at a higher latitude when Mars’ rotational tilt was different.

Either way, the massive geology here illustrates the monumental nature of this largest canyon in the solar system, as well as the difficulties of exploring it.

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The evidence keeps pouring in showing the utter failure of all COVID mandates

2:38 pm

Since March 2020 I have repeatedly written that the response to the Wuhan flu was an utter mindless panic that had little to do with the facts. Right off the bat, the facts, not the models, suggested the virus would resemble the flu most of all, a possible mortal threat to the sick and elderly but generally nothing more than a short sickness to the general population, with it being almost utterly harmless to the young.

Nothing that has happened since has really changed these early conclusions. I have compiled below a collection of recent studies and reports that illustrate what we have learned following the epidemic and the panic that accompanied it. Sadly, that panic did little to stop the virus, but it left us with destroyed businesses, a crushed economy, many uneducated and damaged children, and a broken Bill of Rights.

The COVID jab

The failure of the jab in the United Kingdom
Study from November 2021showing the overall uselessness of the jab
in the United Kingdom last year.

The first set of stories show some recent studies analyzing the effectiveness and safety of the COVID shots, which are not vaccines because they simply do not prevent you from getting the virus. At best — though not yet proven — they might reduce the severity of the disease should you get it. The data however now suggests that though the overall risks are not large, the jab carries enough risk that in many cases, it makes no sense to get it. To require it, as many governments and businesses have done, is downright stupid and immoral. To fire nurses and doctors for refusing the shots is beyond stupid or immoral. It is evil.

Worse, these facts were known right from the initial tests, as the last story below shows. In the company’s initial trials they found that 1,223 people died within the first 28 days after taking the Pfizer shot. Such a result in past drug trials would have made impossible the approval of that drug.
» Read more

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Scientists propose new theory to explain mysterious slope streaks on Mars

10:28 am

Slope streaks on Mars
Click for full image.

In a paper published earlier this month, scientists have proposed a new theory to explain the the origin of slope streaks on Mars, a unique Martian geological feature that at first glance look like a stainlike avalanches which also appear to do nothing to change the surface topography. (See earlier posts here and here for a description of this strange Martian phenomenon.)

Essentially, data from the orbiters suggests that carbon dioxide frost develops just under the surface during the night. In equatorial regions this frost mixes with dust (allowing it to exist even in these warmer climates). When the morning light hits the frost it causes it to sublimate away, which in turn causes the appearance of slope streaks as the dust is released from the frost.

From the paper’s abstract:

At sunrise, sublimation-driven winds within the regolith are occasionally strong enough to displace individual dust grains, initiating and sustaining dust avalanches on steep slopes, forming ground features known as slope streaks. This model suggests that the CO2 frost cycle is an active geomorphological agent at all latitudes and not just at high or polar latitudes, and possibly a key factor maintaining mobile dust reservoirs at the surface.

The cool image above, cropped and reduced to post here, was taken on October 28, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows an excellent example of two very spectacular large slope streaks, one long and narrow and another short and wide. Located at 23 degrees, this is an area where no ice has yet been found near the surface.

This new theory joins two other popular theories attempting to explain slope streaks. The others postulate that the streaks are either dust avalanches of a different type or the percolation of a brine of chloride and/or perchlorate in a thin layer several inches thick close to the surface.

None have been proven. None likely fit all the known data at this point.

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