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Baby white sharks can't tell difference between humans and seals: Study – ABC News

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Juvenile white sharks are responsible for the majority of bites on swimmers.

Swimmers beware: Hungry sharks do think you’re food.

Young white sharks, which are responsible for the majority of attacks on people, can’t distinguish between humans and seals, according to new research.

To test the theory of “mistaken identity theory” behind shark bites, researchers in Australia compared video footage of typical prey with images of humans swimming and paddling surfboards from the perspective of a juvenile white shark.

The researchers designed a virtual visual system based on what’s known about the vision of juvenile white sharks and viewed the images of the swimmers and prey using that filter, Laura Ryan, a neurobiologist at Macquarie University in Sydney and author of the study, told ABC News.

Researchers found the sharks could not distinguish between the motion cues or shapes of the prey and humans, proving that humans and seals look “dangerously similar” from a shark’s perspective, according to the study, published Tuesday in the Royal Society Journals. The researchers also found that, to juvenile sharks, swimmers and paddling surfers appeared similar to that of seals with their flippers abducted.

Sharks have lower spatial resolution than humans, meaning they don’t see in as much detail, and they’re colorblind, Ryan said, adding that scientists hypothesize that as younger sharks mature, they become more experienced hunters and rely more on other sensory cues.

“So, potentially, these older adults are more experienced, enhanced, so they might not make as many mistakes,” she said. “Also, as an animal grows, its eye gets bigger, and so that means that their spatial acuity gets bigger, so they are able to distinguish a bit more detail.”

Ryan emphasized that the researchers studied “unprovoked” attacks, such as those on swimmers and surfers, whereas a provoked shark attack may be defensive or aggressive disturbance in response to a direct disturbance by a human, such as a diver touching a shark or someone spear fishing.

White sharks, bull sharks and tiger sharks are the species responsible for the most injuries and fatal bites, according to the study.

One of the reasons the researchers embarked on this study is to help the “public perception” of sharks, Ryan said.

Shark bites, while rare, can have “devastating” effects on victims and first responders, and they can harm local businesses if tourism declines, according to the study. Bites also have negative consequences for shark populations, as they often result in the implementation of lethal shark mitigation measures.

Ryan added that researchers are studying some non-invasive mitigation efforts, such as changing the visual cues on surfboards — using an LED counter-illumination to change the silhouette shape of the surfboard from below — to reduce or prevent shark bites.

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Stargazer in Italy spots NASA's DART asteroid impact probe in night sky after launch – Space.com

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An Italian telescope captured NASA’s asteroid-smashing mission shortly after its launch into space this week. 

A new image and video, taken by the Elena telescope located in Ceccano, Italy, shows NASA’s Double Asteroid Redirection Test mission, also known as DART, separated from the second stage of the Falcon 9 rocket which launched the spacecraft from Vandenberg Space Force Base in California on Tuesday (Nov. 23 PST, or early Nov. 24 EST) . The mission sent DART on a 10-month-long journey to a binary asteroid system called Didymos

Both DART and the booster can be seen in this image (above), which was taken remotely with a single 30-second exposure, astronomer Gianluca Masi said in a statement. Masi runs the Virtual Telescope Project 2.0, which includes the Elena telescope.

The image was taken remotely 10 hours after DART lifted off, Masi said.

Related: NASA’s DART asteroid-impact mission explained in pictures

NASA’s DART spacecraft and a Falcon 9 second stage booster that launched it can be seen as two small dots at the center of this image capture a few hours after the mission’s launch. (Image credit: The Virtual Telescope Project)

The robotic Elena telescope automatically tracked DART and the booster, both of which are visible at the center of the image as bright dots. The short white lines surrounding those two dots are stars in the background. When the image was taken, DART was about 93,000 miles (150,000 kilometers) from Earth, about half the distance between our planet and the moon, Masi said. 

In addition to the static image, the telescope also captured a short video sequence, which shows the separated second-stage booster blinking. This blinking, Masi said, is caused by the booster spinning. 

The pioneering DART mission will conduct a first-of-its-kind test that will show if and how a spacecraft can change the path of an asteroid by smashing into it. In September of next year, the spacecraft will ram into a 525-foot-wide (160 meters) asteroid “moonlet” known as Dimorphos, which orbits the larger space rock Didymos. The goal of the experiment is to alter Dimorphos’ orbit around Didymos, shortening it by several minutes, to prove that such an intervention could divert the trajectory of a large asteroid if, in the future, one were to be on a path that threatened planet Earth.

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DART also carries a small cubesat called LICIACube, from Italy’s space agency, which will be released 10 days ahead of DART’s self-destructive impact and film the aftermath of the crash. 

In 2024, the European Space Agency (ESA) will also send a larger surveyor spacecraft called Hera to the asteroid system that will analyze the crater and gather data about Didymos’ and Dimorphos’ physical structure and chemical composition. By then, astronomers will have known whether DART deflected Dimorphos, thanks to ground-based observations. 

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook

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Russia’s new module on ISS to offer docking opportunity for foreign spacecraft in future – TASS

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KOROLYOV /Moscow Region/, November 26. /TASS/. NASA and Roscosmos have begun talks on harmonizing technical standards of Crew Dragon spaceships with the Russian module and Russian spacecraft with the US segment on the International Space Station (ISS), Roscosmos Chief Dmitry Rogozin said at the Flight Control Center on Friday.

“NASA and Roscosmos have launched talks on harmonizing technical standards that will allow not only Crew Dragon or Russian spaceships to dock with the American segment but, in general, this docking is possible and will require an adapter,” Rogozin said, replying to a question about whether US spacecraft would be able to dock to Russia’s new Prichal nodal module.

The Prichal module’s docking completed the formation of the ISS Russian segment, the Roscosmos chief said.

The Prichal nodal module will also serve as a prototype for similar modules for the future Russian Orbital Service Station (ROSS) that will be the ‘joints’ of its space body, Rogozin said.

“This is one of the most important prototypes for creating the ROSS whose architecture will differ from the ISS. It should employ the principle of eternal service life: modules that use up their potential will be detached from the station and it will be augmented in a different direction with the help of such nodal modules that will serve as some joints of a new and large metal design engineering body,” Rogozin said.

A Soyuz-2.1b carrier rocket with the Progress M-UM space freighter and the Prichal nodal module blasted off from Launch Pad No. 31 (‘Vostok’) of the Baikonur spaceport to the orbital outpost at 16:06 Moscow time on November 24. The flight to the orbital outpost took two days. The Prichal module docked with the Russian Nauka research lab on November 26.

The new module will boost the capabilities of Russian spaceships, including the latest Oryol spacecraft, to dock with the ISS. Overall, the new module will have five docking ports. The first docking of a manned spacecraft with the Prichal module is scheduled for March 18.

The spacecraft-module also delivered about 700 kg of various cargo to the ISS, including equipment and consumables, water purification, medical control including sanitary and hygienic supplies, maintenance and repair tools, as well as standard food rations for the 66th Main Expedition crew.

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Italy and France sign agreement on space launchers

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 Italy and France clinched an accord on Friday to strengthen their cooperation on space launchers as part of a broader bilateral treaty.

Among the goals laid out in the bilateral treaty were pledges to reinforce military connections, including at an industrial level, and work together in the space sector.

The two countries agreed to work together on liquid and solid propulsion and press ahead with the development of launchers Ariane 6 and Vega C, Italy’s innovation minister and France’s economy minister said in a joint press release.

Launchers are the second largest area of space-manufacturing activity in Europe after commercial satellites, according to the European Space Agency (ESA).

For the development of Ariane 6, ESA is working with more than 600 companies in 13 European countries, led by prime contractor ArianeGroup, which is a joint venture of Airbus and Safran.

ESA is overseeing procurement and the architecture of the overall Vega-C launch system, while industry is building the rocket with Italy’s Avio as prime contractor.

 

(Reporting by Francesca Landini; Editing by Frances Kerry)

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