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Scientists investigate why females live longer than males – Newswise

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Newswise — An international team of scientists studying lifespans of wild mammals have found that, just like humans, females tend to live significantly longer than their male counterparts.

The researchers looked at the lifespans of 101 different species, from sheep to elephants, and found that females lived an average of 18% longer than males for more than 60% of the species studies. In humans, females tend to live around 7.8% longer.

The study, led by scientists at University Lyon 1 and published in the prestigious journal, Proceedings of the National Academy of Sciences, found this was not due to the sexes aging at different rates but that females had an average lower risk of mortality in adulthood than males.

It was unclear from the data as to why females survive longer than males, however the authors suggest that it could be due to complex interactions between the local environmental conditions and sex-specific costs of reproduction.

Professor Tamás Székely, from the Milner Centre for Evolution at the University of Bath, was one of the authors of the study. He said: ‘We’ve known for a long time that women generally live longer than men, but were surprised to find that the differences in lifespan between the sexes was even more pronounced in wild mammals than in humans.

“This could be either because females are naturally able to live longer, or that female mortality drops compared with males.

“For example, lionesses live at least 50% longer in the wild than male lions. We previously thought this was mostly due to sexual selection – because males fight with each other to overtake a pride and thus have access to females, however our data do not support this. Therefore there must be other, more complex factors at play.

“Female lions live together in a pride, where sisters, mothers and daughters hunt together and look after each other, whereas adult male lions often live alone or with their brother and therefore don’t have the same support network.

“Another possible explanation for the sex difference is that female survival increases when males provide some or all of the parental care. This is also true in birds. Giving birth and caring for young becomes a significant health cost for females and so this cost is reduced if both parents work together to bring up their offspring.”

The researchers plan to compare the data on wild animals with that of captive zoo animals, which do not have to deal with predators or competition for food or mates. This will allow them to measure the extent to which biological differences between the sexes have an effect on life expectancy.

“By affecting males and females differently, harsh environmental conditions such as a high prevalence in pathogens, is likely to cause sex-differences in lifespan.

“Comparing the sex gap in lifespan and aging across several populations of the same species is definitely full of promises,” said Jean-François Lemaître from the National Centre for Scientific Research (University Lyon 1, France) and coordinator of this study.

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The research, supported by the Royal Society and the French National Research Agency (CNRS), was a collaboration between scientists from France, the UK, Finland, USA, New Zealand, Hungary and Germany.

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Celebrate Yuri's Night 2020 online with Bill Nye, astronauts and more this weekend! – Space.com

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This Saturday (April 11), 50 years after Apollo 13 launched to the moon, you can celebrate human spaceflight with a Yuri’s Night livestream event. 

Yuri’s Night events have been held annually since 2001 and were originally designed as a way to celebrate human spaceflight. The event is named after cosmonaut Yuri Gagarin, who became the first human to go to space on April 12, 1961. 

In addition to the main annual Yuri’s Night event, including music, art, science and more, people also independently throw their own “Yuri’s Nights” all around the world however they want in whatever location they want.

Related: Vostok 1: How the First Human Spaceflight Worked (Infographic)

However, while “there is no ‘typical’ Yuri’s Night party,” Tim Bailey, executive director of Yuri’s Night, told Space.com in an email, this weekend will certainly be different from previous celebrations. “This year almost all local events have been canceled to help slow the spread of the coronavirus,” he said. The closures also mean that the annual event will be livestreamed. 

But the online event will feature an all-star cast of scientists, artists and astronauts who will be participating in the event. Spaceflyers taking part include South Korean astronaut Soyeon Yi, Canadian astronaut Chris Hadfield and retired NASA astronauts Nicole Stott and Scott Kelly, Bailey said, while other guests include celebrity science communicator Bill Nye, former rocket scientist and current CEO of Girl Scouts of the USA Silvia Acevedo, founding member of the Grateful Dead Bob Weir and “Star Trek: Voyager” actor Robert Picardo.

Alongside the livestream, Yuri’s Night will hold a costume contest to mark the occasion, so don your favorite flight suit or get creative and make an imaginative space-inspired costume with things you already have at home. You could even win “fabulous prizes,” Bailey said, if you enter your costume by posting it on Twitter with the hashtag #YurisNight. 

You can watch the livestream and stay up-to-date with the evolving list of guests here

Follow Chelsea Gohd on Twitter @chelsea_gohd. Follow us on Twitter @Spacedotcom and on Facebook.

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Mercury-bound spacecraft buzzes Earth, beams back pictures – CityNews Edmonton

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CAPE CANAVERAL, Fla. — A Mercury-bound spacecraft swooped past Earth on Friday, tweaking its round-about path to the solar system’s smallest and innermost planet.

Launched 1 1/2 years ago, Europe and Japan’s Bepi-Colombo spacecraft passed within 8,000 miles (12,700 kilometres) of Earth. The closest approach occurred over the South Atlantic, with telescopes in Chile catching a glimpse of the speeding spacecraft.

The gravity tug from Earth slowed Bepi-Colombo and put it on a course closer to the sun.

It was the first of nine planetary gravity assists — and the only one involving Earth — on the spacecraft’s seven-year journey to Mercury. The spacecraft — comprised of two scientific orbiters — should reach Mercury in 2025, after swinging twice past Venus and six times past Mercury itself. The next flyby will be at Venus in October.

Before leaving Earth’s vicinity, Bepi-Colombo beamed back black-and-white pictures of the home planet. The spacecraft holds three GoPro-type cameras.

“These selfies from space are humbling, showing our planet, the common home that we share, in one of the most troubling and uncertain periods many of us have gone through,” Gunther Hasinger, the European Space Agency’s science director, said via Twitter.

The space agency’s control centre in Germany had fewer staff than usual for Friday’s operation because of the coronavirus pandemic. The ground controllers sat far apart as they monitored the flyby. Data from the flyby will be used to calibrate Bepi-Colombo’s science instruments.

Scientists hope to learn more about the origin and composition of Mercury, once the European and Japanese orbiters separate and begin their own circling of the scorched planet.

Mercury is the least explored of our solar system’s four rocky planets. It’s just a little bigger than our moon and circles the sun in just 88 days.

The spacecraft is named after Italian mathematician and engineer Giuseppe “Bepi” Colombo, who devised the use of planetary flybys for Mercury encounters. He died in 1984.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Marcia Dunn, The Associated Press

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50 years after Apollo 13, we can now see the moon as the astronauts did – Space.com

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This Saturday (April 11) will mark 50 years since NASA’s Apollo 13 mission launched on an unexpectedly tumultuous journey around the moon. Now, a modern lunar orbiter has reconstructed what the Apollo 13 astronauts would have seen of the lunar surface. 

Famously described as a “successful failure,” Apollo 13 did not go as planned: An oxygen tank exploded 56 hours into the mission. Thankfully, some fast-thinking teamwork between the astronauts and mission control back on Earth salvaged the mission and, after a trip around the moon, the astronauts safely returned to Earth. 

So, while the crew didn’t land on the moon as planned, they did travel around it and, thanks to modern technology, we can now see what they saw on this journey. 

Related: Apollo 13 in Real-Time website offers new insight into mission

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A photo of the lunar surface taken by the Apollo 13 astronauts on their trip around the moon. (Image credit: NASA)

A photo of the lunar surface taken by the Apollo 13 astronauts on their trip around the moon. 

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Soon after sunrise, the Apollo 13 crew snapped this incredible shot of the moon.

Soon after sunrise, the Apollo 13 crew snapped this incredible shot of the moon. (Image credit: NASA)

Soon after sunrise, the Apollo 13 crew snapped this incredible shot of the moon. 

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A snapshot of the Tsiolkovskiy crater, taken by the Apollo 13 crew with a telephoto lens.

A snapshot of the Tsiolkovskiy crater, taken by the Apollo 13 crew with a telephoto lens. (Image credit: NASA)

A snapshot of the Tsiolkovskiy crater, taken by the Apollo 13 crew with a telephoto lens. 

Researchers used data from NASA’s Lunar Reconnaissance Orbiter mission to recreate what the Apollo 13 crew saw as they flew around the far side of the moon. In the video, you can see craters and other lunar features emerge from the darkness. You can imagine yourself as any of the crewmembers — commander Jim Lovell, command module pilot Jack Swigert or lunar module pilot Fred Haise — looking down and watching the lunar surface pass by as the spacecraft flew overhead. 

In addition to the Lunar Reconnaissance Orbiter data, the researchers also consulted the Apollo 13 flight plan and, despite the major change in plans with the mission, were able to use the position and speed at the craft’s closest point to the Moon which was listed in the Apollo 13 Mission Report. Taken together, those details allowed them to determine factors including the position and speed of the spacecraft at its closest point to the moon, which helped clarify the vehicle’s trajectory. 

To create this virtual trip around the moon, this team was also informed by photos taken by the Apollo 13 crew during this trip around the moon. You can see some of the captivating original images above, but you can also find every Apollo 13 photo ever online in the Apollo Image Atlas

Follow Chelsea Gohd on Twitter @chelsea_gohd. Follow us on Twitter @Spacedotcom and on Facebook.

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