NASA's Mars Perseverance rover acquired this image using its left Mastcam-Z camera on Thursday. Mastcam-Z is a pair of cameras located high on the rover's mast. Photo courtesy of NASA | License Photo
Perseverance documents the Martian surface. Photo courtesy of NASA | License Photo
The Martian surface is documented is detail from Perseverance. Photo courtesy of NASA | License Photo
The navigation cameras aboard the Mars rover captured this view of the rover’s deck on Monday. This view provides a look at PIXL (the Planetary Instrument for X-ray Lithochemistry), one of the instruments on the rover’s stowed arm. Photo courtesy of NASA/JPL-Caltech
This panorama, made by the navigation cameras aboard Perseverance, was stitched together from six individual images after they were sent back to Earth. Subsequent missions, currently under consideration by NASA in cooperation with the European Space Agency, would send spacecraft to Mars to collect these cached samples from the surface and return them to Earth for in-depth analysis. Photo courtesy of NASA/JPL-Caltech
This is the first high-resolution, color image to be sent back by the Hazard Cameras (Hazcams) on the underside of NASA's Perseverance Mars rover after its landing on February 18. Photo courtesy of NASA | License Photo
This high-resolution still image, from the camera aboard the descent stage, is part of a video taken by several cameras as NASA's Perseverance rover touched down on Mars. Photo courtesy of NASA | License Photo
Perseverance can be seen falling through the Martian atmosphere in the descent stage, its parachute trailing behind, in this image taken on Thursday by the High-Resolution Imaging Experiment camera aboard the Mars Reconnaissance Orbiter. The ancient river delta, which is the Perseverance mission's target, can be seen entering Jezero Crater from the left. Photo courtesy of NASA | License Photo
An illustration depicts the rover driving in the foreground across the plain of Jezero Crater, where the robotic explorer landed safely. Image courtesy of NASA
An image showing where Perseverance Mars rover landed is shown during a NASA Perseverance rover mission post-landing update, on February 18, at NASA's Jet Propulsion Laboratory in Pasadena, Calif. Photo by Bill Ingalls/NASA | License Photo
Members of NASA's Perseverance Mars rover team watch in mission control as the first images arrive moments after the spacecraft successfully touched down on Mars. Photo by Bill Ingalls/NASA | License Photo
The first photos taken by NASA's Perseverance Mars rover after landing on the Martian surface. A key objective for Perseverance's mission on Mars is astrobiology, including the search for signs of ancient microbial life. Photo courtesy of NASA | License Photo
These computer simulations show Perseverance landing on the Martian surface. The rover will characterize the planet's geology and past climate, paving the way for human exploration of the Red Planet and be the first mission to collect and cache Martian rock and regolith. Image courtesy of NASA | License Photo
In this illustration of its descent to Mars, the spacecraft carrying NASA's Perseverance rover slows down using the drag generated by its motion in the Martian atmosphere. Hundreds of critical events must execute precisely on time for the rover to land on Mars safely. Entry, descent, and landing, or "EDL," begins when the spacecraft reaches the top of the Martian atmosphere, traveling nearly 12,500 mph. The cruise stage separates about 10 minutes before entering into the atmosphere, leaving the aeroshell, which encloses the rover and descent stage, to make the trip to the surface. Image courtesy of NASA | License Photo
An illustration of Perseverance on Mars, launched from Earth in July. It is the fifth rover to successfully reach Mars, and is the first of three that may return rocks samples to Earth. Image courtesy of NASA | License Photo
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The view from inside Jezero crater.Image: NASA/JPL-Caltech/ASU
NASA’s Perseverance rover has been on Mars for a full week, and the images are starting to pour in. Here are our favorites so far.
The six-wheeled rover landed in Jezero crater on Feb. 18, and the Mars 2020 team is busily preparing Perseverance for the science stage of the mission. But that hasn’t stopped the rover from snapping some seriously interesting pics, which NASA is making available. As of this posting, the space agency has uploaded more than 5,600 raw images to the publicly available archive, so yeah, the SUV-sized rover has been very active, at least in the photography department.
The supersonic parachute during descent.Image: NASA/JPL-Caltech
While drifting towards the surface of Mars, the spacecraft’s Parachute Up-Look Camera A snapped this really neat photo, showing the parachute from a rather unique perspective. Only later was it revealed that a code was hiding in the red and white patterns. Internet sleuths managed to crack it, finding that it reads “dare mighty things,” which happens to be the motto at NASA’s Jet Propulsion Laboratory. The GPS coordinates for JPL in Pasadena, California, are also hidden in the patterns on the parachute’s outer ring.
The ejected heat shield falling towards the surface.Image: NASA/JPL-Caltech
The spacecraft ejected its heat shield when the rover was approximately 4 miles (6.4 kilometers) above the surface. According to Al Chen, Perseverance EDL lead at JPL, a spring responsible for pushing the heat shield away appears to have come loose. This didn’t affect the mission, but it obviously was not supposed to happen.
A view of the landing site as Perseverance was making its descent.Image: NASA/JPL-Caltech
This is one of many images taken by the rover’s Down-Look Camera during the descent. Intriguing geological features are visible, including some interesting stratigraphy at top left. Billions of years ago, Jezero crater was filled with water and fed by a rushing river.
Another view taken by the Down-Look camera.Image: NASA/JPL-Caltech
Here’s a closer view of that area, showing a large crater and dune-like patterning on the surface. NASA has chosen an excellent place to land, as Jezero crater appears to be a geologically busy place.
Hi-res image showing the rover seconds before reaching the Martian surface.Image: NASA/JPL-Caltech
You’re probably familiar with this photo by now, but if you’re like me, you’ll never tire of seeing it. It shows Perseverance during the “skycrane” landing maneuver, as the rover is being lowered to the surface by its rocket-powered backshell.
The view on Mars.Image: NASA/JPL-Caltech/ASU
Wow. Thanks to Percy, we know what it’s like to stand on an alien world and gaze off into the horizon. This image was taken by the Mastcam-Z camera located on the rover’s mast. In total, the rover is equipped with 23 different cameras.
A Martian scene.Photo: NASA/JPL-Caltech/ASU
Another spectacular view from inside Jezero crater, again taken with Mastcam-Z. Many rocks are strewn about, which Perseverance will have to avoid while trekking across the surface. That said, the machine is so beautifully designed that it can endure tilts of 45 degrees without falling over.
The first panorama taken by Perseverance.Image: NASA/JPL-Caltech/MSSS/ASU
Behold the first 360-degree panoramic view of the rover’s landing site. The photo was captured on Feb. 21, and it was stitched together from 142 individual images.
Rocks on Mars.Image: NASA/JPL-Caltech/ASU
A close-up view of some rocks near the rover. The quality of these photos are exceptional. Perseverance is designed such that it could easily roll over these obstructions, as its legs will “enable the rover to drive over knee-high rocks as tall as 40 centimeters (15.75 inches),” according to NASA.
A partial view of the rover’s deck.Image: NASA/JPL-Caltech/ASU
The rover’s Mastcam-Z camera was used to snap this image of the rover’s deck, which has already accumulated some dust (likely during the landing). That joystick-like device in the foreground is used to calibrate Mastcam-Z.
The rover’s front left wheel and some rocks.Image: NASA/JPL-Caltech/ASU
This wonderful Mastcam-Z image, in addition to showing us a clear view of the rover’s front left wheel, shows rocks peppered with holes. Geologist Kathryn Stack Morgan, deputy project scientist for the Mars 2020 mission, said similar holes are seen in volcanic rocks, but also sedimentary rocks. The team is keen to find out, as the result will be interesting regardless.
More rocks with holes.Image: NASA/JPL-Caltech/ASU
Another view of those pockmarked rocks. Once the mission gets rolling, the rover’s SuperCam will be used to “identify the chemical composition of rocks and soils, including their atomic and molecular makeup,” according to NASA.
The “family portrait” of probes sent to Mars.Image: NASA/JPL-Caltech/ASU
The hidden code in the parachute wasn’t the only Mars 2020 Easter egg. A family portrait of all five wheeled rovers sent to Mars has been spotted on Percy’s deck. From left to right they are: Sojourner, Spirit, Opportunity, Curiosity, and Perseverance. And check out the tiny helicopter at far right—that’s Ingenuity, which is currently strapped to the belly of the rover.
The view directly beneath Perseverance.Image: NASA/JPL-Caltech
Here’s the view from directly beneath the rover, which Perseverance captured with its Down-Look camera.
A view of the Sun.Image: NASA/JPL-Caltech
Percy used its Left Navigation Camera to snap this neat photo of the Sun. A day on Mars is referred to as a sol, which lasts for 24 hours and 39 minutes and 35 seconds.
A study released this week shows how the tyrannosaurus consumed different resources at multiple stages of growth. Modern meat-eating mammals can easily be arranged in a chart showing average adult size – each of these animals have a unique effect on their own ecosystem. Given the average size of adult dinosaurs, there appeared to be a massive gap in the middle of the chart from smallest to largest.
A gap exists in the chart of adult meat-eating dinosaurs for each of the three main periods of the Mesozoic. The Triassic, Jurassic, and Cretaceous have a serious lack of medium-sized “meat eating meat-asauruses” (as Ariana Richards’ Lex called them in Jurassic Park).
Why in modernity do we have carnivores in a neat range, from small to lion-sized, but back in dinosaur times, we didn’t? Researchers From the University of New Mexico and the University of Nebraska proposed a new theory: Morphospecies.
ABOVE: Fig. 3 The dinosaur gap versus modern carnivorous mammals. (A) Carnivorous mammals of Kruger National Park organized to scale by mass. (B) Carnivorous dinosaurs of Dinosaur Park Formation if the largest carnivore were scaled equally to the largest mammalian carnivore in Kruger. Infants (gray) of the largest species shown below adult to show relative growth requirement. IMAGE, DESCRIPTION: UNM Biology Department.
You might’ve heard about the shift from the old way of thinking about dinosaurs and the new, the shift over the past few decades that reduced the number of individual species of dinosaurs from a lot to… significantly less than previously suspected. If you’ve never seen the TED Talk with Jack Horner about “Shape-shifting dinosaurs”, I suggest you take the time to do so – it’s one of the most-watched TED Talks in the history of TED Talks.
Keep this in mind as you read the rest of of the paper published this week by researchers (as outlined above). The old way of thinking about each individual set of bones as a new dinosaur allowed scientists to see a range of dinosaur sizes that was far more “complete”, like we see with carnivores in modernity. When people like Jack Horner came around, that theory was shattered.
Now, with this latest research, the morphospecies theory makes sense of the shattered pieces of this puzzle. We don’t see individual meat-eating dinosaurs filling every size gap from small to large because dinosaurs like T-rex were there, capitalizing on their entire range of sizes as they grew from tiny baby, just out of an egg, to most massive meat-eater of them all.
Tyrannosaurus was so effective a carnivore that it had a significant impact on the ecosystem in which it lived at every stage of growth. Why have mid-ranged carnivore dinosaurs when you could just have more T-rex?
For more information, take a peek at the paper “The influence of juvenile dinosaurs on community structure and diversity” as published in Science. This paper was authored by Katlin Schroeder, S. Kathleen Lyons, and Felisa A. Smith. Research can be found with code DOI:10.1126/science.abd9220 as published in Science Volume 371, Issue 6532, February 26, 2021.
Near the Markha River in Arctic Siberia, the earth ripples in ways that scientists don't fully understand.
Earlier this week, NASA researchers posted a series of satellite images of the peculiar wrinkled landscape to the agency's Earth Observatory website. Taken with the Landsat 8 satellite over several years, the photos show the land on both sides of the Markha River rippling with alternating dark and light stripes. The puzzling effect is visible in all four seasons, but it is most pronounced in winter, when white snow makes the contrasting pattern even more stark.
Why is this particular section of Siberia so stripy? Scientists aren't totally sure, and several experts offered NASA conflicting explanations.
One possible explanation is written in the icy ground. This region of the Central Siberian Plateau spends about 90% of the year covered in permafrost, according to NASA, though it occasionally thaws for brief intervals. Patches of land that continuously freeze, thaw and freeze again have been known to take on strange circular or stripy designs called patterned ground, scientists reported in a study published in January 2003 in the journal Science. The effect occurs when soils and stones naturally sort themselves during the freeze-thaw cycle.
The stripes covering a portion of the Central Siberian Plateau vary by season.(Image credit: NASA Earth Observatory)
However, other examples of patterned ground — such as the stone circles of Svalbard, Norway — tend to be much smaller in scale than the stripes seen in Siberia.
Another possible explanation is erosion. Thomas Crafford, a geologist with the U.S. Geological Survey, told NASA that the stripes resemble a pattern in sedimentary rocks known as layer cake geology.
These patterns occur when snowmelt or rain trickles downhill, chipping and flushing pieces of sedimentary rock into piles. The process can reveal slabs of sediment that look like slices of a layer cake, Crafford said, with the darker stripes representing steeper areas and the lighter stripes signifying flatter areas.
In accordance with the image above, this sort of sedimentary layering would stand out more in winter, when white snow rests on the flatter areas, making them appear even lighter. The pattern fades as it approaches the river, where sediment gathers into more uniform piles along the banks after millions of years of erosion, Crafford added.
This explanation seems to fit well, according to NASA. But until the region can be studied up close, it'll remain another one of those quintessentially Siberian curiosities.
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This wind-carved "Harbor Seal Rock," seen in the first 360-degree panorama taken by the Mastcam-Z instrument on NASA’s Perseverance Mars rover, shows just how much detail is captured by the camera system.(Image credit: NASA/JPL-Caltech/MSSS/ASU)
NASA's Perseverance rover has landed in a rich scientific hunting ground, if its first good look around is any guide.
The car-sized Perseverance landed on the floor of Jezero Crater on Feb. 18, kicking off an ambitious surface mission that will hunt for signs of ancient Mars life and collect samples for future return to Earth, among other tasks.
Perseverance is not yet ready to dive into that science work; the mission team is still conducting health and status checks on its various instruments and subsystems. But the six-wheeled robot recently used its Mastcam-Z camera suite to capture a high-definition, 360-degree panorama of its surroundings, and that first taste has the mission team intrigued.
For example, the zoomable panorama revealed a dark stone that the team has dubbed "Harbor Seal Rock," Mastcam-Z principal investigator Jim Bell, of Arizona State University's School of Earth and Space Exploration, said during a webcast discussion of the photo on Thursday (Feb. 25).
The Martian wind probably carved Harbor Seal Rock into its curious shape over the eons, Bell said. He also pointed out patches that showed evidence of much faster-acting erosion — spots where the thrusters on Perseverance's "sky crane" descent stage blew away Mars' blanket of red dust on Feb. 18, exposing the surfaces of small rocks.
One such patch harbors a group of light-colored, heavily pitted stones that have caught mission scientists' eyes.
"Are these volcanic rocks? Are these carbonate rocks? Are these something else? Do they have coatings on them?" Bell said. "We don't know — we don't have any chemical data or mineral data on them yet — but, boy, they're certainly interesting, and part of the story about what's going on here is going to be told when we get more detailed information on these rocks and some of the other materials in this area."
This is one of the key jobs of Mastcam-Z and Perseverance's other cameras, Bell said — to spot interesting features that Perseverance can study in more detail with its spectrometers and other science instruments.
The 28-mile-wide (45 kilometers) Jezero Crater harbored a deep lake and a river delta billions of years ago. Deltas are good at preserving signs of life here on Earth, so the Perseverance team is eager for the rover to study and sample the remnants of that feature within Jezero. And the delta is visible in the Mastcam-Z panorama; the cliffs that mark its edge are about 1.2 miles (2 kilometers) from Perseverance's landing site, Bell said.
The ridgeline that's visible beyond the delta cliffs in the Mastcam-Z panorama is Jezero Crater's rim, he added.
The recently unveiled photo is just the beginning, of course. For starters, it's the lowest-resolution panorama the Mastcam-Z team will construct. Bell said that similar shots that are three times sharper will be assembled after Perseverance switches over to its surface-optimized software, a four-day process that's already underway.
And we haven't gotten the slightest taste of Perseverance's science discoveries yet. That work will take a while to get going, because the mission team's first big task after getting the rover up and running is to conduct test flights of the 4-lb. (1.8 kilograms) Mars Helicopter Ingenuity, which rode to the Red Planet on Perseverance's belly.
Ingenuity's pioneering sorties — the first rotorcraft flights on a world beyond Earth — will likely take place this spring, and science and sampling are expected to begin in earnest in the summer, mission team members have said.
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.
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An influential current system in the Atlantic Ocean, which plays a vital role in redistributing heat throughout our planet's climate system, is now moving more slowly than it has in at least 1,600 years. That's the conclusion of a new study published in the journal Nature Geoscience from some of the world's leading experts in this field.
Scientists believe that part of this slowing is directly related to our warming climate, as melting ice alters the balance in northern waters. Its impact may be seen in storms, heat waves and sea-level rise. And it bolsters concerns that if humans are not able to limit warming, the system could eventually reach a tipping point, throwing global climate patterns into disarray.
The Gulf Stream along the U.S. East Coast is an integral part of this system, which is known as the Atlantic Meridional Overturning Circulation, or AMOC. It was made famous in the 2004 film "The Day After Tomorrow," in which the ocean current abruptly stops, causing immense killer storms to spin up around the globe, like a super-charged tornado in Los Angeles and a wall of water smashing into New York City.
As is the case with many sci-fi movies, the plot is based on a real concept but the impacts are taken to a dramatic extreme. Fortunately, an abrupt halting of the current is not expected anytime soon — if ever. Even if the current were to eventually stop — and that is heavily debated — the result would not be instant larger-than-life storms, but over years and decades the impacts would certainly be devastating for our planet.
Recent research has shown that the circulation has slowed down by at least 15% since 1950. Scientists in the new study say the weakening of the current is "unprecedented in the past millennium."
Because everything is connected, the slowdown is undoubtedly already having an impact on Earth systems, and by the end of the century it is estimated the circulation may slow by 34% to 45% if we continue to heat the planet. Scientists fear that kind of slowdown would put us dangerously close to tipping points.
Importance of the Global Ocean Conveyor Belt
Because the equator receives a lot more direct sunlight than the colder poles, heat builds up in the tropics. In an effort to reach balance, the Earth sends this heat northward from the tropics and sends cold south from the poles. This is what causes the wind to blow and storms to form.
The majority of that heat is redistributed by the atmosphere. But the rest is more slowly moved by the oceans in what is called the Global Ocean Conveyor Belt — a worldwide system of currents connecting the world's oceans, moving in all different directions horizontally and vertically.
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Through years of scientific research it has become clear that the Atlantic portion of the conveyor belt — the AMOC — is the engine that drives its operation. It moves water at 100 times the flow of the Amazon river. Here's how it works.
A narrow band of warm, salty water in the tropics near Florida, called the Gulf Stream, is carried northward near the surface into the North Atlantic. When it reaches the Greenland region, it cools sufficiently enough to become more dense and heavier than the surrounding waters, at which point it sinks. That cold water is then carried southward in deep water currents.
Through proxy records like ocean sediment cores, which allow scientists to reconstruct the distant past going back millions of years, scientists know that this current has the capacity to slow and stop, and when it does the climate in the Northern Hemisphere can change quickly.
One important mechanism through the ages, which acts as a lever of sorts controlling the speed of the AMOC, is the melting of glacial ice and resulting influx of fresh water into the North Atlantic. That's because fresh water is less salty, and therefore less dense, than sea water, and it does not sink as readily. Too much fresh water means the conveyor belt loses the sinking part of its engine and thus loses its momentum.
That's what scientists believe is happening now as ice in the Arctic, in places like Greenland, melts at an accelerating pace due to human-caused climate change.
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Recently scientists have noticed a cold blob, also known as the North Atlantic warming hole, in a patch of the North Atlantic around southern Greenland — one of the only places that's actually cooling on the planet.
The fact that climate models predicted this lends more evidence that it is indicative of excess Greenland ice melting, more rainfall and a consequent slowdown of heat transport northward from the tropics.
Almost all of the globe is warming except for a cold blob in the North Atlantic.NASA
In order to ascertain just how unprecedented the recent slowing of the AMOC is, the research team compiled proxy data taken mainly from nature's archives like ocean sediments and ice cores, reaching back over 1,000 years. This helped them reconstruct the flow history of the AMOC.
The team used a combination of three different types of data to obtain information about the history of the ocean currents: temperature patterns in the Atlantic Ocean, subsurface water mass properties, and deep-sea sediment grain sizes, dating back 1,600 years.
While each individual piece of proxy data is not a perfect representation of the AMOC evolution, the combination of them revealed a robust picture of the overturning circulation, says lead author of the paper, Dr. Levke Caesar, a climate physicist at Maynooth University in Ireland.
"The study results suggest that it has been relatively stable until the late 19th century," explains Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research in Germany.
The first significant change in their records of ocean circulation happened in the mid 1800s, after a well-known regional cooling period called the Little Ice Age, which spanned from the 1400s to the 1800s. During this time, colder temperatures frequently froze rivers across Europe and destroyed crops.
"With the end of the Little Ice Age in about 1850, the ocean currents began to decline, with a second, more drastic decline following since the mid-20th century," said Rahmstorf. That second decline in recent decades was likely due to global warming from the burning and emissions of fossil fuel pollution.
Nine of the 11 data-sets used in the study showed that the 20th century AMOC weakening is statistically significant, which provides evidence that the slowdown is unprecedented in the modern era.
Impact on storms, heat waves and sea-level rise
Caesar says this is already reverberating in the climate system on both sides of the Atlantic. "As the current slows down, more water can pile up at the U.S. East Coast, leading to an enhanced sea level rise [in places like New York and Boston]," she explained.
On the other side of the Atlantic, in Europe, evidence shows there are impacts to weather patterns, such as the track of storms coming off the Atlantic as well as heat waves.
"Specifically, the European heat wave of summer 2015 has been linked to the record cold in the northern Atlantic in that year – this seemingly paradoxical effect occurs because a cold northern Atlantic promotes an air pressure pattern that funnels warm air from the south into Europe," she said.
According to Caesar, these impacts will likely continue to get worse as the Earth continues to warm and the AMOC slows down even further, with more extreme weather events like a change of the winter storm track coming off the Atlantic and potentially more intense storms.
CBS News asked Caesar the million-dollar question: If or when the AMOC may reach a tipping point leading to a complete shutdown? She replied: "Well, the problem is that we don't know yet at how many degrees of global warming to hit the tipping point of the AMOC. But the more it slows down the more likely it is that we do."
Moreover, she explained, "Tipping does not mean that this happens instantaneously but rather that due to feedback mechanisms the continued slow down cannot be stopped once the tipping point has been crossed, even if we managed to reduce global temperatures again."
Caesar believes if we stay below 2 degrees Celsius of global warming it seems unlikely that the AMOC would tip, but if we hit 3 or 4 degrees of warming the chances for the tipping rise. Staying below 2 degrees Celsius (3.6 degrees Fahrenheit) is a goal of the Paris Agreement, which the U.S. just rejoined.
If the tipping point is crossed and the AMOC halts, it is likely the Northern Hemisphere would cool due to a significant decrease in tropical heat being pushed northward. But beyond that, Caesar says that science does not yet know exactly what would happen. "That is part of the risk."
But humans do have some agency in all this, and the decisions we make now in terms of how quickly we transition away from fossil fuels will determine the outcome.
"Whether or not we cross the tipping point by the end this century depends on the amount of warming, i.e. the amount of greenhouse gases emitted to the atmosphere," explains Caesar.
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