Tag: science

Mars: Are these eroding glaciers or impacts in lava?

1:38 pm

Eroding lava or glaciers?
Click for original image.

Cool image time and a mystery! The photo to the right, cropped to post here, was taken on March 29, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) of an 18-mile-wide crater in the southern cratered highlands of Mars. The full picture, dubbed “Steep Cliff,” was taken apparently to get a good view of the crater’s northern rim. The rim’s steepness suggests that the floor of the crater is significantly filled.

More intriguing however are the scattering of strange depressions about six miles south of the rim. What caused them? The crater’s location is in a part of Mars where it is not unusual to find both glacial features as well as flood plain lava. In fact, the crater’s northeast and southwest rims appear to have been buried by what appears to be flood lava. The northern rim’s shallowness also suggests the crater is well filled with flood lava.

However, the crater is also at 38 degrees south latitude, a latitude where planetary scientists have found lots of glacial features. Much of this crater fill could be glacial.

The overview map below illustrates this mystery.
» Read more

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A pair of spiral galaxies

2:02 pm

IC 4271, or AP 40, a pair of active galaxies
Click for full image.

Another cool image to herald in the weekend! The photo to the right, cropped and reduced to post here, was taken by the Hubble Space Telescope and shows a pair of spiral galaxies about 800 million light years away.

The smaller galaxy is superimposed on the larger one, which is a type of active galaxy called a Seyfert galaxy.

Seyfert galaxies are named for astronomer Carl K. Seyfert who, in 1943, published a paper about spiral galaxies with very bright emission lines. Today we know that about 10% of all galaxies may be Seyfert galaxies. They belong to the class of “active galaxies” – galaxies that have supermassive black holes at their centers accreting material, which releases vast amounts of radiation. The active cores of Seyfert galaxies are at their brightest when observed in light outside the visible spectrum. The larger galaxy in this pair is a Type II Seyfert galaxy, which means it is a very bright source of infrared and visible light.

In other words, both of these galaxies emit a lot of radiation in the infrared, radio, and X-rays due to activity taking place at the supermassive black holes believed to be at their cores.

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Dry flows on Mars?

1:50 pm

Flows in Orson Welles Crater
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and annotated to post here, was taken on September 21, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows what appear to be a variety of flows, from alluvial fill to slope streaks to dust coming down the southeastern interior rim of 77-mile-wide Orson Welles Crater on Mars.

The location is almost right on the equator, so none of these flows are ice- or water-related. Nor are such flows unusual in the meandering 800-mile-long canyon that cuts through Orson Wells crater, dubbed Shalbatana Vallis. I featured similar flows at a spot to the north and downstream from this one in May 2021, also on the canyon’s eastern rim.

The overview map below provides some context.
» Read more

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Perseverance’s upcoming travel plans

10:12 am

Overview map
Click for interactive map.

Today’s update from the Perseverance’s science team provided a rough outline of their travel and drill-sampling plans for the Mars rover in Jezero Crater as it begins its climb up onto the delta that once poured into the crater. The route they plan to travel initially is dubbed Hawksbill Gap.

At Hawksbill Gap, however, we may instead carry out the first portion of the sampling sol path (which includes abrasion and collecting observations using our proximity science instruments) at up to 5 locations along our ascent. After that, we’ll turn around and begin a descent back down Hawksbill Gap and collect rock core samples at 3 of our abrasion locations.

This modified sampling strategy is intended to provide the team with valuable contextual information as we climb Hawksbill Gap and interpret the delta stratigraphy around us. With proximity science data in-hand, we can down-select our sampling sites to ensure we’ll be collecting the most scientifically valuable cores along our descent. Of course, we still maintain the option of collecting sample cores at any point during our ascent, if the team decides a particular abrasion site warrants immediate sampling.

The map above shows my guess (the red dotted lines) as to their potential routes uphill. As the science team has so far not published a map indicating exactly where Hawksbill Gap is, I can only guess at this point. The blue dot indicates Perseverance’s present position, the green dot Ingenuity.

As for the helicopter, there is no word yet whether the engineers have successfully gotten its batteries back to full charge. Until then, it cannot fly, and is also at risk of freezing up in the cold Martian winter.

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Zhurong goes into hibernation

9:30 am

Overview map

According to a report today in China’s state-run press, the team running its Zhurong Mars rover have placed it into a hibernation mode in order to sit out the Martian winter.

To tackle the dust storms and low-temperature challenges, the Chinese rover went into dormancy on Wednesday. It is expected to wake up and resume work in December when the dust clears and Mars enters its spring season, the administration said in a statement.

The rover sits somewhere in the blue circle in the map to the right, created using elevation data and images from Mars Reconnaissance Orbiter (MRO). This region is about 25 degrees north latitude, so though it is in the dry equatorial regions of Mars, it still gets very cold in winter, down to -180 degrees Fahrenheit at night. Furthermore, the increased winter dust storms block the light from the Sun, which reduces the available power the rover’s solar panels can produce.

Chinese engineers have apparently adapted the hibernation techniques they use on the Moon with their Yutu-2 rover to place Zhurong in hibernation.

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ESA releases new images from Solar Orbiter

10:53 am

The Sun's south pole, as seen by Solar Orbiter at perihelion
The Sun’s south pole, as seen by Solar Orbiter at perihelion. Click for full movie.

The European Space Agency (ESA) yesterday released a few of the images taken by its Solar Orbiter spacecraft before and during its first perihelion (closest point in its orbit) on March 26, 2022.

The spacecraft was inside the orbit of Mercury, at about one-third the distance from the Sun to the Earth, and its heatshield was reaching around 500°C. But it dissipated that heat with its innovative technology to keep the spacecraft safe and functioning.

Solar Orbiter carries ten science instruments – nine are led by ESA Member States and one by NASA – all working together in close collaboration to provide unprecedented insight into how our local star ‘works’. Some are remote-sensing instruments that look at the Sun, while others are in-situ instruments that monitor the conditions around the spacecraft, enabling scientists to ‘join the dots’ from what they see happening at the Sun, to what Solar Orbiter ‘feels’ at its location in the solar wind millions of kilometres away.

The photo above, cropped, reduced, and revised slightly to post here, looks at the Sun’s south pole, from the side. The surface of the Sun (the top two thirds) almost looks like thunderheads on Earth, except the rain coming from them are high energy heat and radiation.

The data produced a lot of fascinating short movies, all available at the link, including a phenomenon the scientists have nicknamed a “space hedgehog” because of its look. About 15,000 miles across, “At present no one knows exactly what it is or how it formed in the Sun’s atmosphere.”

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Puzzling telemetry from Voyager-1 suggests problem

9:49 am

Engineers are puzzling over strange operational data coming from Voyager-1, launched in 1977 and now in interstellar space more than 14 billion miles away, that suggests a technical problem but also makes no sense.

The engineering team with NASA’s Voyager 1 spacecraft is trying to solve a mystery: The interstellar explorer is operating normally, receiving and executing commands from Earth, along with gathering and returning science data. But readouts from the probe’s attitude articulation and control system (AACS) don’t reflect what’s actually happening onboard.

The AACS controls the 45-year-old spacecraft’s orientation. Among other tasks, it keeps Voyager 1’s high-gain antenna pointed precisely at Earth, enabling it to send data home. All signs suggest the AACS is still working, but the telemetry data it’s returning is invalid. For instance, the data may appear to be randomly generated, or does not reflect any possible state the AACS could be in.

The issue hasn’t triggered any onboard fault protection systems, which are designed to put the spacecraft into “safe mode” – a state where only essential operations are carried out, giving engineers time to diagnose an issue. Voyager 1’s signal hasn’t weakened, either, which suggests the high-gain antenna remains in its prescribed orientation with Earth.

Figuring out what has happened is made more difficult by distance. It takes about 20 hours for signals to get from Voyager-1 to Earth, even at the speed of light. Thus, any attempted fix will arrive almost two days after it first occurred, at the soonest.

Both Voyager-1 and Voyager-2 are still operating, though at significantly reduced power. It is expected that sometime in the next few years their nuclear power sources will finally be unable to produce enough power to keep them functioning. If so, both spacecraft will have survived the maximum time predicted when launched.

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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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