It suggests that humpback whales are nearsighted and often collide with objects.

Recent studies indicate that humpback whales often collide with objects due to their surprisingly limited vision.

This gentle giant struggles to discern fine details until it is quite close, which may explain the unfortunate incidents of these animals becoming entangled in fishing nets or crashing into small vessels.

To gain insights into how humpback whales perceive their surroundings, a group of marine biologists examined the left eye of a deceased whale after it had been stranded.

In the study, the researchers found that the rear part of the whale’s eye was considerably thicker than anticipated. This suggests that the distance from the retina to the lens (the eye’s focal length) is much shorter than expected.

A shorter focal length implies that the whale’s capability to resolve finer details is significantly lower than previously believed.

This theory was further supported by the team’s count of the neurons responsible for transmitting visual information to the brain, which revealed a stark contrast.

While a typical human eye has around 40,000 retinal ganglion cells per square millimeter, humpback whales possess only about 180.

Humpback whales are known to collide with small boats as they fail to detect them – Credits: Getty Images/Marnie Griffith

This level of poor vision typically doesn’t hinder whales, but Professor Lori Schweikert from the University of North Carolina Wilmington noted in BBC Science Focus.

“Apart from prey, humans, and some bird species, many animals possess relatively low vision,” says Schweikert.

“However, their visual capabilities are often adequate for their survival needs in their natural habitats. For humpback whales, they may primarily need to recognize large shapes, such as a big school of prey or other swimming whales.”

Humpbacks can identify large objects from a distance, but finer details come into focus only when they are about 45-60 meters away, or within 3-4 lengths of their bodies.

This means whales may struggle to see thin strands of fishing nets.

“At close range, they should be able to identify such structures,” Schweikert adds.

About our experts

Professor Lori Schweicart serves as an assistant professor of biology and marine biology at the University of North Carolina Wilmington. Her research centers on the physiological mechanisms involved in light reception within marine settings.

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Source: www.sciencefocus.com

There is a high probability that Asteroid 2024 YR4 will not collide with Earth in 2032.

Astronomers raced to observe asteroid 2024 YR4

NASA/Magdalena Ridge 2.4M Telescope/New Mexico Institute of Technology/Ryan

The world’s space agency has reduced the chance that asteroid 2024 YR4 will affect Earth by less than 1%. This strongly suggests that potentially catastrophic conflicts will be avoided. However, the asteroid probably passes very extraordinarily close to our planet, giving astronomers a rare opportunity to observe the asteroid in close proximity.

“We don’t expect the impact probability above 1% will exceed 1% in 2032 due to our close approach with the Earth,” he says. Richard Moisle With the European Space Agency (ESA). “The most likely further development is a further reduction in impact probability, perhaps even dropping to zero.”

The alarm last December regarding the asteroid 2024 YR4 was first raised in December last year, when it discovered it could be on Earth’s collision course in 2032. It looks like it’s 40-90 meters wide and can produce a fatal explosion if attacked by a city. Over the next few weeks, global telescopes and space agencies have closely tracked their orbits, honing their future paths more accurately. On February 17th, we reached our highest shock risk with one in 32nd chance, but in the next few days this reduced to a 67th or 1.5% risk.

On February 20th, new observations led to a sudden downgrade of this risk, with NASA having a 0.27% impact chance of 1-in-360, and ESA having a 0.16%, or 1-in-in-in- in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in-in- in-ine 625. These ratings placed it at 1 on a 10-point Turin scale used to evaluate the hazards brought about by such objects. That score has decreased from 3. So, 2024 YR4 is now considered one of many low-risk asteroids discovered each year, but ultimately misses Earth.

I say this is good news Gareth Collins At Imperial College in London, asteroids still serve as a dry run for planetary defense systems and scientific purposes. “This still makes for an epic, close approach. If the risk of a hit was so high, it must be close to us,” he says.

Space companies that were sketching possible schemes to deflect NASA, ESA and asteroids, say they will likely continue their plans. Niklas Voight At OHB, a German space company. Voigt and his team were beginning to think about the mission to deflect the 2024 YR4, but the new risks won’t change that, he says. “The risk has decreased, but for the time being, we are still working on the topic.”

A close approach could be a good opportunity to test its ability to deflect asteroids, says Voigt – the only previous attempt to do this was NASA’s DART mission, the 160m in 2022 The asteroid-shaped trajectory of the . Satellites can be constructed to send to the 2024 YR4, he says, as well as the ESA’s Ramses satellite, to travel to observe the asteroid Apophis, passing near Earth in 2029. It is set to do so.

The final decision on what to do about YR4 2024 will likely not be made until the planned observation in March using James Webb Space Telescope. Not only does it collect orbital data, it also helps to better assess the size and composition of the asteroid. That information will be provided to the UN Assisted Space Mission Planning Advisory Group, which will determine the best action around the end of April. “These are very useful exercises to find a pinch point to make a decision, as you have time to do something wise in advance,” Collins says. “Absolutely, these committees are still meeting, but they’re probably less stressful.”

The possibility of an Earth shock has plummeted, but the risk of a YR4 collision with the moon in 2024 rose from 0.3% to 1.2%. “There’s a clear possibility that those numbers will rise even further,” says Moissl. “The exact impact of the effects of the moon from objects of this size is still under evaluation.”

The response to this object is also a useful rehearsal for other asteroids of concern, Collins says. “We want to avoid screams in the future, as the public is used to this threat, thinking, ‘Oh, that’s never going to happen.’ ”

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Source: www.newscientist.com