'This species is very special': Granddaddy of the spider discovered by ROM researchers - CBC News - Canadanewsmedia
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'This species is very special': Granddaddy of the spider discovered by ROM researchers – CBC News

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It boasts a pair of bulgy egg-shaped eyes, a dorsal skeleton that resembles a shield of sharp armour, and numerous pairs of limbs that could grasp, crush and chew.  

And it’s name is a mouthful: Mollisonia plenovenatrix.   

Fossils uncovered by an expedition team from the Royal Ontario Museum in Toronto have led to the discovery of this thumb-sized sea-dwelling predator that predates arachnids, the family that includes spiders and scorpions.

It was a pair of fang-like appendages at the front of the creature’s mouth that most excited ROM paleontologist Jean-Bernard Caron, whose findings were published Wednesday in the science journal Nature.

The appendages, called chelicerae, meant the species was a member of the family Chelicerate. Not only that, it was that family’s oldest known ancestor, at about 506 million years old.

Mollisonia plenovenatrix shown from side view. The creature is defined by its fang-like pincers, called chelicerae, seen at the front of its head. It used them to kill, hold and sometimes cut its prey. (Submitted by ROM)

Chelicerate is a group that is familiar with everybody because it includes spiders, scorpions and horseshoe crabs. Those represent 115,000 species of animals today. And they are part of an even bigger group called arthropods which are defined by a jointed body and limbs,” said Caron.

But while they are one of the largest groups of species, Caron said “their origin has always been puzzling to scientists.”

That’s why the discovery is so special, he told CBC Toronto.

“It’s important to try to understand the origin of this group. In many ways, these fossils help provide the answer of where they come from. They tell us about the origin of innovations in animal evolution and also about ourselves.”

Top photo shows the chelicerae on a horseshoe crab; bottom shows the fang-like chelicerae of a spider, which can use them to puncture the skin of a victim and inject venom. (Submitted by ROM)

Discovery made at new Burgess Shale site

The fossils were discovered in the world-renowned Burgess Shale located in the Canadian Rockies of southeastern British Columbia. 

It is famous for being one of the earliest fossil beds containing fossil imprints from the Cambrian period, a time when the Earth’s biodiversity exploded.

“What’s exceptional about the Burgess Shale is the preservation of soft tissue. It is extraordinary, the amount of detail we see. We’ve discovered some really early fish,” said Caron.

Since 2012, a ROM expedition team has been uncovering fossils in a new site called Marble Canyon.

But it took detailed observations and research, conducted by Caron and his colleague Cédric Aria, to be certain of their discovery of the Mollisonia.

Even though it is only as big as a thumb, Mollisonia plenovenatrix would have been a fierce predator in its day. Caron and Aria believe it preferred to hunt close to the sea floor due to its well-developed walking legs. (Submitted by ROM)

“The animals lived at the bottom of the sea. They were buried very quickly in the mud that became rock, and they were buried at different angles.”

Bit-by-bit the two paleontologists were able to make out the characteristics of the prehistoric mini-beast from numerous slabs of rock.

“Before this discovery, we couldn’t pinpoint the chelicerae in other Cambrian fossils, although some of them clearly have chelicerate-like characteristics,” said Aria.

Paleontologist Cedric Aria, seen here at the Burgess Shale, says ‘evidence is converging towards picturing the Cambrian explosion as even swifter than what we thought.’ (Submitted by ROM)

An even older ancestor waiting to be discovered?

The fossils also showed the creature having back limbs like gills, suggesting it had already adapted to its watery environment.

“This discovery tells us that at the time of the Cambrian they were already there. They probably evolved earlier than that,” Caron said. 

“We know this is the oldest fossil showing chelicerae. But it’s likely there are fossils before that we haven’t found yet.”

Caron intends to head back to Burgess Shale next summer to continue exploring.

In the meantime, as curator of invertebrate paleontology at the ROM, he is busy planning for a new gallery entitled Dawn of Life.

The Mollisonia will be just one of many fossils from the Burgess Shale that will be on display in the gallery, scheduled to open in 2021.

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Photos Show Evidence of Life on Mars, Claims Scientist – NDTV

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As scientists scramble to determine whether there is life on Mars, a researcher from Ohio University in US believes that there is evidence of insect-like creatures on the red planet.

Courtesy photographs from various Mars rovers, Professor Emeritus William Romoser’s research found numerous examples of insect-like forms, structured similarly to bees, as well as reptile-like forms, both as fossils and living creatures.

“There has been and still is life on Mars,” Romoser said, noting that the images appear to show both fossilised and living creatures.

“There is apparent diversity among the Martian insect-like fauna which display many features similar to Terran insects that are interpreted as advanced groups – for example, the presence of wings, wing flexion, agile gliding/flight, and variously structured leg elements,” Romoser added.

Romoser said that while the Martian rovers, particularly the Curiosity Rover, have been looking for indicators of organic activity, there are a number of photos which clearly depict the insect- and reptile-like forms.

Photo Credit: Ohio University

Numerous photos show images where arthropod body segments, along with legs, antennae and wings, can be picked out from the surrounding area, and one even appears to show one of the insects in a steep dive before pulling up just before hitting the ground.

Individual images were carefully studied while varying photographic parameters such as brightness, contrast, saturation, inversion, and so on. No content was added, or removed.

Criteria used in Romoser’s research included: Dramatic departure from the surroundings, clarity of form, body symmetry, segmentation of body parts, repeating form, skeletal remains, and observation of forms in close proximity to one another.

Particular postures, evidence of motion, flight, apparent interaction as suggested by relative positions, and shiny eyes were taken to be consistent with the presence of living forms.

“Once a clear image of a given form was identified and described, it was useful in facilitating recognition of other less clear, but none-the-less valid, images of the same basic form,” Romoser said. “

An exoskeleton and jointed appendages are sufficient to establish identification as an arthropod.

Three body regions, a single pair of antennae, and six legs are traditionally sufficient to establish identification as ‘insect’ on Earth.

These characteristics should likewise be valid to identify an organism on Mars as insect-like. On these bases, arthropodan, insect-like forms can be seen in the Mars rover photos.”

These creatures loosely resemble bumble bees or carpenter bees on Earth. Other images show these “bees” appearing to shelter or nest in caves. And others show a fossilized creature that resembles a snake.

“The presence of higher metazoan organisms on Mars implies the presence of nutrient/energy sources and processes, food chains and webs, and water as elements functioning in a viable, if extreme, ecological setting sufficient to sustain life,” Romoser said.

“The evidence of life on Mars presented here provides a strong basis for many additional important biological as well as social and political questions,” he added.

The study was presented at Entomological Society of America national meeting.

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Starlink Satellites Posing Issues For Astronomers – Hackaday

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Spotting satellites from the ground is a popular pastime among amateur astronomers. Typically, the ISS and Iridium satellites have been common sightings, with their orbits and design causing them to appear sufficiently bright in the sky. More recently, SpaceX’s mass launches of Starlink satellites have been drawing attention for the wrong reasons.

A capture from the Cerro Telolo observatory, showing the many Starlink satellite tracks spoiling the exposure.

Starlink is a project run by SpaceX to provide internet via satellite, using a variety of techniques to keep latency down and bandwidth high. There’s talk of inter-satellite laser communications, autonomous obstacle avoidance, and special designs to limit the amount of space junk created. We’ve covered the technology in a comprehensive post earlier this year.

The Starlink craft have long worried astronomers, who rely on a dark and unobstructed view of the sky to carry out their work. There are now large numbers of the satellites in relatively low orbits, and the craft have a high albedo, meaning they reflect a significant amount of the sunlight that hits them. With the craft also launching in a closely-packed train formation, there have already been impacts on research operations.

There is some hope that as the craft move to higher orbits when they enter service, this problem will be reduced. SpaceX are also reportedly considering modifications to the design to reduce albedo, helping to keep the astronomy community onside. Regardless, with plans on the table to launch anywhere from 12,000 to 42,000 satellites, it’s likely this isn’t the last we’ll hear about the issue.

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This Is How Elon Musk Can Fix The Damage His Starlink Satellites Are Causing To Astronomy – Forbes

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CLARAE MARTÍNEZ-VÁZQUEZ / CTIO

In any field of business or industry, the prevailing rule has always been that if there isn’t a law against it, you are free to do it. If there are no rules protecting a resource, you are free to use or take as much of it as you want to further your own ends. Until regulatory measures are put into place, disruptors and innovators are free to regulate themselves, often to the extraordinary detriment of those who depended on those now-scarce resources.

In astronomy, the greatest resource of all is a dark, clear night sky: humanity’s window to the Universe. Traditionally, its enemies have been turbulent air, cloud cover, and artificial light pollution. But very recently, a new type of pollutant has begun to pose an existential threat to astronomy itself: mega-constellations of satellites. If Elon Musk’s Starlink project continues as it has begun, it will likely end ground-based astronomy as we know it.

Getty

Launching satellites to provide services to those of us living on the ground is an essential part of modern-day living. GPS and telecommunications satellites enable our cellular signals and support our mobile internet today. With the coming upgrade to 5G services, a new set of infrastructure will be required, and that necessarily means an upgraded set of satellites equipped to provide that service must be launched.

One of the first companies to attempt to serve this market is SpaceX, under the guidance of Elon Musk, which plans to initially deploy 12,000 satellites in a mega-constellation known as Starlink. Ultimately, the constellation hopes to extend to a total of 42,000 satellites. As of November 20, 2019, only 122 of these satellites have been deployed, and they’ve already had a detrimental impact on astronomy on a global scale.

If we hope to mitigate this, either regulators or SpaceX executives themselves will need to mandate a change.

Richard Ryer of Panoramio

From the darkest skies you can find on Earth, approximately 9,000 stars are visible to human eyes: down to a visual magnitude of +6.5, the limit of human vision. Yet the first 122 satellites launched by Starlink are not only brighter than the majority of these stars, they move quickly throughout the sky, leaving trails that pollute astronomers’ data.

If these satellites were either faint, few in number, or slowly moving, this would be only a mild problem. If you’re only observing a narrow region of the sky, you’d simply reject any exposure frames (or even just the pixels from them) where the offending objects streak across the sky. But with large numbers of bright, rapidly moving satellites, particularly if you’re searching for changes from frame-to-frame (like many current and future observatories are designed to do), you have to throw out any exposure frame with these artifacts in them.

CLIFF JOHNSON / CTIO / DECam

On November 18, 2019, a series of 19 of these Starlink satellites passed over the Cerro Tololo Inter-American Observatory’s site in Chile, lasting for more than 5 minutes and heavily affecting the wide-field DECam instrument, which images a field containing 3 square degrees at an outstanding 0.263 arcsecond-per-pixel resolution.

Even though this only represents 0.3% of the total number of proposed Starlink satellites that SpaceX wants to launch, the consequences are clear: wide-field astronomy designed to look for faint objects — prime goals of observatories like Pan-STARRS, LSST, and any observing program geared towards finding potentially Earth-hazardous objects — is going to be significantly hindered. Averaging over frames is not a desired option, because it erases astronomers’ ability to study the natural variability of object, another important science goal. Because Starlink satellites autonomously change their orbits and are extremely radio-loud, ground-based observations cannot be scheduled so as to avoid them.

NASA illustration courtesy Orbital Debris Program Office

In addition, these satellites are not in traditional low-Earth orbits, which will decay and fall back to Earth on timescales of months, years, or (at most) decades, these satellites are at elevations of over 1,000 km, where orbital decay will take millennia. Already, back in September, the ESA’s Aeolus satellite (used for Earth observation) had to make an emergency maneuver to avoid colliding with a SpaceX Starlink satellite, despite the fact that it was SpaceX’s responsibility to move.

Although SpaceX and Musk have issued statements claiming that:

all of these statements are not yet true as of November 20, 2019.

Getty

Previous constellations of satellites, such as the extremely successful Iridium constellation, proceeded in clearly defined and predictable orbits, were few in number (66 total), and only flared brightly when their orientation reflected sunlight in a particular manner. The Starlink satellites, along with similar planned constellations such as Kuiper Systems and OneWeb, pose a new and unique hurdle for ground-based astronomy.

According to Cees Bassa from the Netherlands Institute for Radio Astronomy, up to 140 such satellites will be visible at any one time from every observatory on Earth. However, if the companies behind these new constellations are willing to take just a few simple steps, all of these hurdles can be overcome. Here’s what a responsible steward of the night sky ought to do, and how SpaceX can undo the damage they’re in the process of inflicting on astronomy.

NASA/ESA/Bill Moede and Jesse Carpenter

1.) De-orbit the current batch of Starlink satellites, and place a moratorium on the launch of new ones until the proper modifications have been made. Unlike most of the GPS and communications satellites we have today, the current Starlink satellites are large, reflective, and already causing some astronomers to throw out significant portions of their data. Currently at an altitude of 280 km, where they’re visible to the naked eye, they can now easily and safely be de-orbited.

But once they’re raised to their operational altitude of 550 km, they become a much more permanent problem. In addition, public awareness will drop, but they will remain visible to all binoculars and telescopes: the astronomer’s most essential tools. Every moment that these satellites are up there is the astronomical equivalent of callously rollin’ coal in the face of every scientist, researcher, and especially the undergraduate and graduate students who rely on hard-to-obtain telescope time in order to start their careers.

SpaceX / Space.com

2.) Either redesign or coat the satellites to significantly reduce their reflectivity. Part of the problem with these new satellites is that they’re both large and highly reflective. But these problems are unnecessary: they’re choices. Choosing a different design, where the satellites can be oriented to minimize the impact on astronomy, would ameliorate the problem. Even more cost-effectively, simply coating the satellites with a very dark, low-albedo outer layer would go a long way to reducing the astronomically polluting effects of this constellation.

Albedo reduction, it is very clear from the current Starlink satellites, was not even considered as part of the design. By incorporating some common sense steps to reduce it — and I know plenty of astronomers willing to help with recommendations — the apparent brightness of these satellites can be reduced by a factor of approximately ~100.

IAU/ Victoria Girgis/ Lowell Observatory

3.) Provide real-time trajectory plans, predictions, and adjustment information for each satellite to observatories worldwide. One of the worst things about these satellites is that they come without predictable trajectories. If their paths were known, astronomers could schedule observations that absolutely minimized their impact on the science, making good use of every moment of good seeing.

It should be not only easy, but mandatory, to set up a global network that tracked the predicted paths of each satellite in real-time, updated continuously to account for any maneuvers or course-corrections that were taken. By providing this information to astronomers, the polluted areas can be avoided at any moment in time, while still taking quality observations of as much of the sky as possible.

SpaceX via Twitter

4.) Provide funding to assist astronomers in the development of hardware and software-driven solutions to subtracting out as much of the satellite pollution as possible. Even if all of these steps are taken, it will still be an arduous and expensive task for astronomers to account for the contamination that remains in their data. It’s unreasonable to expect that Starlink or any satellite-based company will have no impact on astronomy at all, but it’s extremely reasonable to demand that they fund the mitigation efforts astronomers will need to take.

This is how literally every other industry in the world works: if you plunder some aspect of the natural environment, you must make restitution for the damage that you caused. The astronomers that I know don’t care that you have satellites up there; they care that they’re still able to do their work despite them. It really isn’t too much to ask.

Starlink (simulation)

Right now, the Outer Space Treaty only prohibits the militarized use of space; all peaceful purposes are allowed. There are no consequences for damages done to the night sky and no regulations on pollution or contamination. So long as you register your satellite(s) and don’t cause an in-orbit or on-Earth collision, there is no legal liability to what you do.

The astronomical community’s only options are either to attempt to get laws passed protecting the night sky, or to hope that the industry will self-regulate. If companies like SpaceX, Kuiper Systems and OneWeb take the altruistic route of addressing these issues in advance of causing widespread problems, they will truly be worthy captains of this burgeoning industry. But it’s very scary to be entering an era where the future of one of humanity’s oldest sciences depends on the ethical compasses of a few profit-driven companies. Our understanding of the Universe, from nearby hazardous objects to the distant recesses of space, is no longer in the hands of astronomers.

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