Tag: science

Images taken during OSIRIS-REx sample grab on Bennu

3:40 pm

Below is an embed of a short eight second video of OSIRIS-REx’s sample grab yesterday from the surface of Bennu, created from 82 images, and covering at high speed the five minutes of approach, contact, and retreat. If you set the speed rate at 0.25, you can get a better view of the whole sequence of events.

From the science team’s press release,

The spacecraft’s sampling arm – called the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – is visible in the lower part of the frame. The round head at the end of TAGSAM is the only part of OSIRIS-REx that contacted the surface during the sample collection event. In the middle of the image sequence, the sampling head positions itself to contact the asteroid’s surface head-on. Shortly after, the sampling head impacts site Nightingale and penetrates Bennu’s regolith. Upon initial contact, the TAGSAM head appears to crush some of the porous rocks underneath it. One second later, the spacecraft fires a nitrogen gas bottle, which mobilizes a substantial amount of the sample site’s material. Preliminary data show the spacecraft spent approximately 5 of the 6 seconds of contact collecting surface material, and the majority of sample collection occurred within the first 3 seconds.

The TAGSAM is designed to catch the agitated surface material, and the mission team will assess the amount of material collected through various spacecraft activities. After touchdown, the spacecraft fired its thrusters to back away from Bennu. As expected, this maneuver also disturbed the Nightingale site, and loose debris is visible near the end of the image sequence. Preliminary telemetry shows the spacecraft remains in good health. The spacecraft was traveling at 0.2 mph (10 cm/sec) when it contacted sample site Nightingale and then backed away at 0.9 mph (40 cm/sec). [emphasis mine]

At the moment it appears they don’t yet know how much sample they have gotten, but they are very optimistic that they have gotten enough, based on the performance above. On October 24th, when they have gotten far enough away from the asteroid, they give the spacecraft a spin to measure its present mass and compare that to a spin done prior to the sample grab. The difference will tell them how much sample they have captured.

They will also be looking at images of TAGSAM over the next few days, which will also indicate what’s been captured.

3 comments

The dying COVID-19 epidemic

9:03 am

Daily mortality from COVID-19 in the United States

Daily mortality and number of cases of COVID-19 in California

The time has come for another update on the state of the COVID-19 epidemic in the United States, mostly because the evidence, as shown in the updated graphs to the right, continues to tell us that the epidemic is dying off, both in its deadliness and in its spread, despite what some ignorant and power-hungry politicians from both political parties might be saying.

There is also no evidence yet of a second wave of the virus, something that these same fear-mongering politicians have been touting. Both the national graph to the right as well as the graph showing California’s numbers below show this.

There is, however, ample evidence that the number of COVID-19 deaths in the U.S. has been corrupted in order to inflate the totals. CDC data shows almost no flu deaths in 2020, something that is simply not credible. More likely the totals of COVID-19 deaths are a combination of COVID-19 and flu deaths, with all the deaths assigned to the coronavirus because hospitals get more government money by doing so.

This combination suggests that all told this epidemic is essentially comparable to a normal flu season. The 2020 winter season was simply one in which we were hit with two respiratory diseases, one old and one new, and the two combined to make that season worse than normal.

To confirm what I have just written however I will let my new GP doctor speak for me. Dr. Robert Lending is certified in both internal medicine and clinical lipidology. Two years ago he became disgusted with the way his practice was evolving due to Obamacare and insurance requirements, both of which were forcing him to see an endless string of patients quickly, with no time to spend with each in order to make sure their needs were covered properly. As noted at his webpage,

In 2018, Dr. Lending decided to return to his roots of delivering personalized, one-on-one health care in a more intimate professional setting. He has partnered with Cypress Concierge Medicine and is now one of a limited number of physicians in the region offering membership-based concierge medicine to patients. This provides more time, attention, and VIP service than patients would experience at your average Internal Medicine provider.

As a result, when I called his office to find out if he would consider my own legitimate medical issues that strongly preclude mask use, he very quickly was willing to listen and work with me. For such concierge service you need to pay an annual retainer, which is not cheap, but based on my experience in the past month, it is well worth every penny. For the first time in more than a decade I actually feel I have a real doctor again, who will spend the time to oversee my medical issues and make sure they are taken care of. For example, I can call him anytime, and he answers the phone. With most modern doctors you never get to talk to them directly, except in your short visits. Instead you have to go through go-betweens, who act to protect the doctor rather than treat the patient.

One of Lending’s services is a periodic email he personally writes and sends to his patients, in which he reviews the most recent medical news of the day. Obviously, for the past six months these updates have been focused mostly on the coronavirus, from the perspective of a doctor in the field. I think what he wrote in yesterday’s email about COVID-19 is most pertinent:
» Read more

30 comments

Penguin highway

6:01 pm

An evening pause: Worth watching more than once, if only to escape the insanity of our time.

I can’t help wondering however why they all are walking on this route, and what is it they stop to look at to the right at one point? And why is one crawling on its belly?

Hat tip Jim Mallamace.

7 comments

Today’s OSIRIS-REx sample grab from Bennu

10:28 am

Nightingale landing site on Bennu
The Nightingale landing site on Bennu, with
OSIRIS-REx superimposed. Click for full image.

Spaceflight Now today published a nicely detailed article summarizing the entire OSIRIS-REx mission to the asteroid Bennu, in anticipation of today’s attempt to grab a sample from that asteroid’s surface.

If you want to understand what is happening today, this article does a nice job of outlining everything.

I have embedded the live stream of the sample grab below the fold. It begins at 5 pm (Eastern) today. Be warned that it will show very little of the actual event, as the spacecraft will not be sending much data back to Earth today, during these operations. All we will really find out is if the grab happened, or was aborted to avoid risks, or occurred but the spacecraft was impacted by flying material during the grab. (Let us hope that this last option does not occur.)

The first images and data will not arrive until tomorrow, to be released during a press conference scheduled for 5 pm (Eastern).
» Read more

4 comments

The face on Jupiter

9:56 am

The face on Jupiter!

Citizen scientist Gerald Eichstädt has created a two-image blink animation from Juno images of Jupiter that shows the changes in the two oppositely rotating storm vortices, shown on the right. As he notes.

Two vortices or eddies, one cyclonic, the other one anticyclonic, can propell themselves mutually and slowly within the overall context they are embedded in.

…The rotation of the two vortices is perceptible in the image sequence taken within nine minutes. The cyclonic eddy is located at the left, the anticyclonic one at the right. The motion of the vortex pair, however, is too slow to be resolved. But the morphology of the cloud tops points towards a relative upward motion in this rendition.

That the two storms also invoke face I am sure also had something to do with his decision to showcase this data. Unlike the face on Mars, this face is real, though relatively temporary. It will eventually break apart as Jupiter’s storms evolve.

The animation can be seen at the link.

6 comments

The edge of Martian chaos

2:05 pm

Overview map of end of Kasei Valles

For today’s cool image, we are going to start from afar and zoom in, because I think that might be the best way to gain at least a rudimentary understanding of the strange geology visible at this one particular Martian location.

The first image, to the right, is the overview map. The red cross indicates our target, a chaotic canyon that flows into the larger Kasai Valles, one of Mars’ largest and longest canyons and possibly only exceeded in size by Valles Marineris. This part of Kasai is near its end, where it drains out into the vast northern lowland plains of Mars.

The second image, below, comes from the wide angle camera on Mars Reconnaissance Orbiter (MRO).
» Read more

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Modern science: Celebrating a “high priestess” instead of data

12:37 pm

The corruption of modern science and our intellectual class was well illustrated today by the following headline and article in the peer review journal Science:

Act now, wait for perfect evidence later, says ‘high priestess’ of U.K. COVID-19 masking campaign

From the article’s lead:

In May, when several prominent U.K. scientists pushed back against a Royal Society report recommending face masks to help control the spread of COVID-19, Trisha Greenhalgh was furious. The scientists argued there was insufficient support in the scientific literature for the efficacy of masks, and the U.K. government, following their lead, declined to mandate masks for the general public.

“The search for perfect evidence may be the enemy of good policy,” Greenhalgh, a physician and expert in health care delivery at the University of Oxford, fumed in the Boston Review. “As with parachutes for jumping out of airplanes, it is time to act without waiting for randomized controlled trial evidence.” [emphasis mine]

The highlighted words have been the typical argument of the global warming crowd for decades. “We can’t wait for evidence! We need to act now before it’s too late!”

Moreover, she — along with the writer of this Science article — also copies another global warming dishonest tactic, posing a false argument by claiming that the opposing scientists requried a “randomized controlled trial” to demonstrate the usefulness of masks. This is an absurd misstatement, as it ignores decades of research that already exists and was referenced by those opposing scientists, that showed that mandating widespread mask use was generally a bad idea, and would accomplish nothing good.
» Read more

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Update on InSight’s mole: It is now underground

9:29 am

InSight's mole now completely buried
Click for full image.

An update today on the mole digging tool on the Mars lander InSight has revealed that the mole appears to finally be completely buried, though it remains unclear whether its most recent digging effort had succeeded in digging downward.

We found that during the first two rounds of hammering and during the first half of the third round of hammering, the scoop went further into the sand. Since the Mole was hidden under the scoop, the penetration of the probe itself could not be observed directly.

During the hammering, the flat tether running to the probe moved considerably, but these could only be clearly identified as forward movements during the hammering on 22 August. Overall, we could estimate from the movements of the scoop that the Mole moved at most one centimetre further into the ground. It was interesting to observe that during the second half of the round of 250 hammer blows on 19 September, the scoop did not go any further, probably because it encountered duricrust. This was certainly a desired outcome, as it allowed a second Free Mole Test to be conducted. In fact, the probe continued to move according to the movements of the tether, but it could not be clearly determined that these movements brought the Mole deeper into the ground.

The image shows InSight’s arm above the filled hole, with the mole’s flat tether coming out of the ground.

They are now going to fill the hole more, and then press down with the scoop during later drilling efforts to see if this allows the mole to proceed downward. If it fails I’m not sure if there is anything else they will be able to do to get the mole to work.

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Study: Almost impossible to contract COVID-19 on an airplane

3:04 pm

New research into the air filtration systems on commercial passenger jets has found that it is almost impossible to contract COVID-19 while on an airplane.

A new military-led study unveiled Thursday shows there is a low risk for passengers traveling aboard large commercial aircraft to contract an airborne virus such as COVID-19 — and it doesn’t matter where they sit on the airplane.

Researchers concluded that because of sophisticated air particle filtration and ventilation systems on board the Boeing 767-300 and 777-200 aircraft — the planes tested for the study — airborne particles within the cabin have a very short lifespan, according to defense officials with U.S. Transportation Command, the Defense Advanced Research Project Agency (DARPA) and Air Mobility Command, which spearheaded the study.

You can read the report [pdf] here. I especially like this quote from their conclusions:

For the 777 and 767, at 100% seating capacity transmission model calculations with a 4,000 viruses/hour shedding rate and 1,000 virus infectious dose show a minimum 54 flight hours required to produce inflight infection from aerosol transmission.

In other words, you can fly around the world more than twice on the same plane, without stopping, without any real risk of getting infected.

Need I add that the use of a mask will likely make no difference either, while probably increasing your chances of catching some disease simply because the long term use of any single mask is unsanitary and almost guarantees it will be carrying pathogens on your face where you breathe?

9 comments

Fingerprints on Mars!

12:53 pm

Fingerprint terrain on the Martian south pole icecap
Click for full image.

No, today’s cool image is not a variation of the absurd “face on Mars” that our alien-obssessed fantasy culture focused on for more than twenty years that turned out to be nothing more than a mesa whose shadows in one image made it look very vaguely like a face.

Instead, today’s cool image is of a very weird Martian geological feature that strongly resembles the whorls and curls seen in all fingerprints, and is thus apply named “Fingerprint Terrain.”

The photo to the right, rotated, cropped, reduced, and annotated to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter on August 26, 2020. It shows part of the surface of Mars’ south pole residual icecap, about 130 miles from the south pole, at a place where the temporary thin dry ice mantle that arrives every winter with the bulk of it sublimating away with the coming of spring.

The fingerprint in this image shows that sublimation process, with the gaps in dry ice mantle getting wider and larger as you move north, until the ridges between disappear altogether.

But why does it look as it does, like a fingerprint? In other places this sublimation process does not look like this at all. Sometimes we get spiderlike formations. Sometimes we get splatters that suggest geysers. Sometimes the surface sublimates to produce swiss cheese shapes. But why a fingerprint here?

I asked this question of Shane Byrne of the Lunar and Planetary Lab University of Arizona, who had requested this particular image, hoping he and other planetary scientists had investigated this geology and come up with an explanation. His answer illustrates how little we yet know about Mars.

It’s almost definitely some sort of sublimation process, but it hasn’t been well investigated. There are some papers that talk about sublimation landforms on the cap in general and map out where different types are, but nothing that I know that’s specific to the fingerprint terrain.

In other words, why the dry ice cap sublimates away in this manner, at this and other locations, remains unexplained.

I’ll say it again: Mars is strange, Mars is alien, and Mars is therefore a place humans must go.

14 comments

Biden-Harris campaign staffers test positive for COVID-19

10:51 am

Two campaign staffers in the Biden-Harris presidential organization have now tested positive for COVID-19.

Kamala Harris has suspended in-person events until Monday after two campaign staffers tested positive for COVID, reports the Associated Press. Harris was supposed to travel to the battleground state of North Carolina on Thursday.

The campaign insists that Joe Biden was not exposed to the virus, but he and Senator Harris spent several hours together last week while campaigning in Arizona. According to the report, Kamala’s communications director and a traveling staff member tested positive after that trip.

My purpose in reporting this really very non-news story is to make two points:

One: Despite so-called strict regimens to protect its campaign people from getting infected, including masks, social distancing, and any number of other procedures now popular in our fear-crazed society, none worked. The infection still arrived, as such infections are guaranteed to do.

Two: No one will die from this outbreak. In fact, it is not even clear anyone will get sick. The Wuhan virus does not kill healthy people. Like the flu, the worst it does is make a healthy person sick for a week or so, after which they recover completely and return to normal life.

We need to stop being so afraid of this virus. It is not the boogie-man it is made out to be, no matter what some people say. It is a variation of the flu, worse for the old who are already very sick, but more harmless for the young and the healthy. With that knowledge in mind we should focus on protecting that very narrow threatened population, while letting everyone else return to a normal life that involves no masks, no social distancing, and above all, no fear.

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Mercury probe BepiColombo probe flies past Venus

9:44 am

Venus during BepiColombo fly-by
Click for full image.

The two-pronged European and Japanese probe BepiColombo today has completed its first of two fly-bys of Venus on its way to an arrival at Mercury in 2025.

The image to the right is one of 64 taken during the fly-by. The science team has created a movie from those images, showing Venus slide past as the spacecraft slewed to view it. During the fly-by the instruments on board its Japanese and European orbiters, both of which will separate and operate independently once they reach Mercury, gathered data of Earth’s sister planet.

The spacecraft still needs one more Venus fly-by plus six past Mercury to get it on a trajectory that will put it in orbit around Mercury. It has also already completed one fly-by past Earth in this complicated route.

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NASA announces broadcast schedule for OSIRIS-REx’s sample grab at Bennu

6:32 pm

NASA today announced the broadcast schedule that will be available to the public of OSIRIS-REx’s sample grab at the asterod Bennu on October 20, 2020.

Much of the schedule is NASA’s public relations blather, filled with some good information intermixed with a lot of lobbying for the government agency. Much of it will also be the equivalent of watching paint dry, as nothing will be happening quickly.

However, if you wish to watch the important part, tune into NASA TV from 5 to 6:30 p.m on October 20th.

Hosted by Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, and Michelle Thaller, science communicator at Goddard, the broadcast will cover milestones in the last 90 minutes leading up to TAG and spacecraft back-away. It will include perspectives from team members and science leaders about the mission’s challenges and accomplishments.

This will be on the public feed. If you find yourself choking on the NASA hype, you can then switch over to the media feed, which will be “A clean feed of the Mission Support Area during TAG [touch-and-go].”

Regardless, the actual attempt will be heart-stopping, because there is a real chance flying rocks from the asteroid’s surface will hit and damage the spacecraft.

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Pluto’s mountains are white-capped but with methane not ice

6:23 pm

Pluto's white-capped mountains
Pluto’s mountains, capped with methane snow.
Click for full figure.

Scientists now theorize that the white-capped mountains first photographed by New Horizons during its 2015 fly-by of Pluto are capped not with ice but with methane snow, as part of that planet’s methane gas-ice cycle.

The image to the right, from their paper, shows these white-capped mountains on Pluto.

The exact composition of this frost on Pluto was unclear. While researchers identified methane, it was unknown whether it is pure frozen methane, frozen methane diluted with frozen nitrogen or a mix of both. The uncertainty about the frost’s composition made it unclear how it might have formed.

To help solve these mysteries, scientists in this new study examined high-resolution data from New Horizons, focusing on the composition of the frost at high altitudes. This new analysis revealed that the snowcap frost “is almost pure methane ice, with traces of nitrogen ice,” Bertrand said.

The researchers also developed high-resolution computer simulations of Pluto’s climate. They focused on how methane circulates around the dwarf planet. [emphasis mine]

Though their simulations of the methane cycle that produces the caps are reasonable, I purposely highlight the fact that this is what they are, and as such must be treated with great skepticism. We might now know the composition of these snowcaps, but our overall knowledge of Pluto remains to limited to trust blindly any computer model.

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Lava cones, fissures, and channels from Olympus Mons

9:11 am

A lava cone, fissure, and channel on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on June 29, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). In this one spot we see three obvious volcanic features, all however formed by different processes.

The location of this image is west of Olympus Mons. It sits on the vast lava plain that was laid down by that volcano, the largest in the solar system.

In order of likely occurrence, the cone probably came first. It likely indicates a past eruption coming up from below to create a small volcano.

The shallow meandering channel that sweeps around it to the north and east probably marks a later lava flow coming down from Olympus Mons.

The deeper straight fissure to the south probably came last. It is a graben, a crack caused by the uplift of the entire surface because of pressure from a magma chamber below, causing cracks to form as the surface is stretched.

Three different volcanic events, each probably taking thousands of years, with maybe thousands to millions of years between them. The context map below adds weight to the scale of time and size represented by this one Martian photo.
» Read more

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Juno science team proposes fly-bys of Jupiter’s moons

8:30 am

The Juno science team has proposed doing fly-bys of three of Jupiter’s moons, should NASA extend the mission beyond ’21.

Juno’s five-year primary mission phase ends in July 2021, and mission managers have proposed an extension that would continue operations until September 2025. The spacecraft’s additional orbits around Jupiter will bring Juno closer to the planet’s moons, allowing for a more diversified set of scientific targets.

…The moon flybys would begin in mid-2021 with an encounter with Ganymede, Jupiter’s largest moon, at a distance of roughly 600 miles (1,000 kilometers), according to Bolton.

After a series of distant passes, Juno would swoop just 200 miles (320 kilometers) above Europa in late 2022 for a high-speed flyby. Only NASA’s Galileo spacecraft, which ended its mission in 2003, has come closer to Europa.

There are two encounters with Jupiter’s volcanic moon Io planned in 2024 at distances of about 900 miles (1,500 kilometers), according to the flight plan presented by Bolton last month.

The extended mission would also allow scientists to get a better look at Jupiter’s north pole.

NASA will decide on the extension by the end of the year. From a cost and scientific perspective, it makes perfect sense to extend this mission for as long as possible. Compared to launching a new mission, extending an active one is far cheaper. It is also already in place.

4 comments

A massive Martian glacier that looks just like a glacier on Earth

2:06 pm

Massive glacier on Mars
Click for full image.

If you ever had any doubt about the existence of glaciers on Mars, today’s cool image should ease those doubts. The photo to the right, taken on August 27, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and rotated, cropped, and reduced to post here, shows many features that are appear identical to features found on typical massive glaciers on Earth.

Downhill is to the northwest. The many parallel grooves or fractures running along the length of the glacier resemble what are seen in many similar Earth glaciers. Some of these fractures are caused by the glaciers slow drift downward, with different sections moving at slightly different rates, thus causing a separation along the flow. Hence the parallel fractures.

These fractures also show evidence of some erosion. Because these Martian glaciers are no longer getting more snowfall, they are no longer growing. However, if the thin layer of dust and debris that protects the ice gets blown off or removed by motion, the ice is exposed and can then sublimate into gas so that the glacier erodes.

On the flow’s edges the darker parallel lines also resemble features seen on Earth, showing the exposed layers of the glacier’s past levels. The same thing can be seen on either side of the canyon’s walls.

The wide smooth section near the center of the parallel lines could very well be an impact crater that landed on this glacier sometime in the far past, and has since been distorted in shape as the glacier flowed downward.

If you still have doubts, the context image below, taken by MRO’s wide angle context camera, should help further allay those doubts.
» Read more

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Astronomers watch star’s destruction as supermassive black hole eats it

10:27 am

Astronomers, using a number of ground-based and orbiting telescopes, successfully observed a star’s destruction as it was ripped apart and eaten by a supermassive black hole at the center of a galaxy 215 million light years away.

The team carried out observations of AT2019qiz, located in a spiral galaxy in the constellation of Eridanus, over a 6-month period as the flare grew in luminosity and then faded away. “Several sky surveys discovered emission from the new tidal disruption event very quickly after the star was ripped apart,” says Wevers. “We immediately pointed a suite of ground-based and space telescopes in that direction to see how the light was produced.”

Multiple observations of the event were taken over the following months with facilities that included X-shooter and EFOSC2, powerful instruments on ESO’s VLT and ESO’s NTT, which are situated in Chile. The prompt and extensive observations in ultraviolet, optical, X-ray and radio light revealed, for the first time, a direct connection between the material flowing out from the star and the bright flare emitted as it is devoured by the black hole. “The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the monster black hole, which is over a million times more massive,” says Nicholl, who is also a visiting researcher at the University of Edinburgh.

Astronomers have seen similar events previously, but never so close and never so early in the event.

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CDC study: Masks do nothing to stop COVID-19 infection

10:52 pm

A new CDC study shows that masks appear to have zero effect in stopping the spread of the COVID-19 virus.

An underreported, recently-published CDC study adds to the pile of evidence that cloth masks or other forms of mandated face coverings only contribute negatives to our COVID-19 problem. The study also displays — despite the constant accusations of widespread misbehavior from public health officials — that Americans are adhering to mask wearing, but mask wearing is not doing us any good.

The CDC study, which surveyed symptomatic COVID-19 patients, has found that 70.6% of respondents reported “always” wearing a mask, while an additional 14.4% say they “often” wear a mask. That means a whopping 85% of infected COVID-19 patients reported habitual mask wearing. Only 3.9% of those infected said they “never” wear a face covering.

The graph below from the study is damning. It shows that wearing a mask made no difference between those who got the disease (left column) and those in the control group.

CDC study graph: masks made no difference.

In either case, the number of cases remained the same no matter how much you wore the mask.

I suspect however that a larger study will find more infections among full-time mask wearers, especially if that study delineates between those medical professionals who are trained to wear the mask properly and with care, keeping it anti-septic, and the general public who fingers their mask continually and then sticks it in their pocket between uses.

27 comments

A lunar landslide

10:03 am

Landslide on the Moon
Click for full image.

Cool image time! The image to the right was posted by the Lunar Reconnaissance Orbiter (LRO) science team on October 9, 2020, and shows a spectacular landslide almost a mile and a half long that had occurred on the interior rim of a crater on the Moon.

The top of the rim is on the left, with the landslide breaking out onto the floor of the crater on the right.

The walls of Kepler crater (30 kilometer diameter) exhibit numerous landslides. In this example, a landslide of dark material begins about 100 meters below the rim from a narrow box canyon. The box canyon is about 50 meters wide and 300 meters long. Overall, the slide is extends some 2300 meters (from the end of the canyon to its base). The base of the slide is on a fault block that lies some 1800 meters below the rim. The wall slope is about 33 degrees.

This slide is actually composed of a series of narrow landslides 20-30 meters wide. Along most of the slope, the individual slides overrun each other forming a band of debris up to about 180 meters wide. At the base of the slope, the individual slides can be recognized as they move apart forming a fan of material. A few individual isolated slides also occur adjacent to the main mass. The overlapping nature of these small slides indicate that the overall feature may have formed over a period of time, rather than all at once.

From above and at this resolution, the landslide looks almost like frozen flowing liquid. It allso looks like it began with a scattering of boulders breaking free at the top all at once that quickly consolidated into a single massive avalanche.

At the link you can zoom in or out to look at the entire image, at full resolution.

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