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ESA's 'interplanetary cargo ship' to carry Mars rocks to Earth in 2031
The Earth Return Orbiter is part of a long-term mission to search for ancient alien life on Mars.

ESA's Earth Return Orbiter
- On July 30, NASA is set to launch the Perseverance rover toward Mars on a mission to search for biosignatures of ancient life within the planet's Jerezo Crater.
- The soil samples collected by the rover would then be launched from the Martian surface into orbit, where a European-made "cargo ship" will intercept the container.
- The cargo ship — a satellite called the Earth Return Orbiter — could return the samples to Earth for further study by 2031.
Was Mars ever home to alien life? If so, scientists believe astrobiological evidence may lie in the ancient rocks and soil of the planet's Jezero Crater, where a lake existed 3.5 billion years ago.
Over the next decade, NASA and European space agencies plan to collect samples from the Jezero Crater and return them to Earth. The mission began at 7:50 a.m. EDT on Thursday, July 30, with the launch of NASA's Perseverance rover, which will embark on a seven-month journey to Mars.
The six-wheeled rover is set to descend to the Martian surface in February 2021. It will then start collecting rock and soil samples that could contain biosignatures of ancient microorganisms — a project that the European Space agency likens to an "interplanetary treasure hunt." Perseverance, previously named the Mars 2020 rover, will store its samples in protective tubes, which it will leave behind for a smaller "fetch rover" to pick up on a future mission.
If all goes well, the fetch rover will transport the samples to a craft called the Mars Ascent Vehicle, which will launch a rocket containing the samples (protected inside of a basketball-sized container) into orbit. A satellite will then intercept the container. To do this, the satellite — an Airbus-France spacecraft dubbed Earth Return Orbiter (ERO) — must carefully position itself to catch the container at the right moment.
In 2031, the ERO will return to Earth, where it will drop the container through our atmosphere to a landing site in North America.
Jerezo Crater landing site
Photo: NASA/JPL-Caltech/USGS/University of Arizona via Wikimedia Commons
It would be the first mission to return Martian matter to Earth.
"This is not just twice as difficult as any typical Mars mission; it's twice squared — when you think about the complexity involved," Dr. David Parker, the director of human and robotic exploration at the European Space Agency (ESA), told BBC News.
"And this satellite that Airbus will build - I like to call it 'the first interplanetary cargo ship', because that's what it will be doing. It's designed to carry cargo between Mars and Earth."
ESA's Earth Return Orbiter
ESA
Finding signs of alien life isn't the rover's only function. The 2,300-pound Perseverance will be equipped with the Ingenuity Mars Helicopter, a small 4-pound drone designed to help scientists learn more about the feasibility of achieving flight on Mars, a planet with an atmosphere that's 99 percent less dense than Earth's.
Perseverance will also carry technology designed to analyze the chemical composition of the Martian surface, study weather, take images of the Martian subsurface, and produce oxygen from Martian atmospheric carbon dioxide — a proof-of-concept method that could someday allow astronauts to produce oxygen for rocket propellant or breathing.
Illustration of the Mars Ascent Vehicle
NASA
But Perseverance's main mission is to find signs of alien life. If it does, that would suggest that life may be relatively common throughout the universe, as Kenneth Farley, the project scientist for Perseverance and a professor at the California Institute of Technology, told The Verge:
"The central question of 'Is there life on other planets?' — it really comes down to: is the origination of life some kind of magic spark that happens only incredibly rarely, or alternatively, is it the kind of thing that is inevitable?" Farley said. "What we can do is we can go to such place in our own solar system on Mars and ask the question, 'Is life ubiquitous?'"
You can watch the Perseverance launch on NASA's YouTube channel at 7:50 a.m. EDT on Thursday, July 30.
Dogs digest human food better and poop less
A new study finds that dogs fed fresh human-grade food don't need to eat—or do their business—as much.
- Most dogs eat a diet that's primarily kibble.
- When fed a fresh-food diet, however, they don't need to consume as much.
- Dogs on fresh-food diets have healthier gut biomes.
Four diets were tested
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjY0NjIxMn0._w0k-qFOC86AqmtPHJBK_i-9F5oVyVYsYtUrdvfUxWQ/img.jpg?width=980" id="1b1e4" class="rm-shortcode" data-rm-shortcode-id="87937436a81c700a8ab3b1d763354843" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />Credit: AntonioDiaz/Adobe Stock
<p>The researchers tested refrigerated and fresh human-grade foods against kibble, the food most dogs live on. The <a href="https://frontierpets.com.au/blogs/news/how-kibble-or-dry-dog-food-is-made" target="_blank">ingredients</a> of kibble are mashed into a dough and then extruded, forced through a die of some kind into the desired shape — think a <a href="https://en.wikipedia.org/wiki/Food_extrusion" target="_blank">pasta maker</a>. The resulting pellets are sprayed with additional flavor and color.</p><p>For four weeks, researchers fed 12 beagles one of four diets:</p><ol><li>a extruded diet — Blue Buffalo Chicken and Brown Rice Recipe</li><li>a fresh refrigerated diet — Freshpet Roasted Meals Tender Chicken Recipe</li><li>a fresh diet — JustFoodforDogs Beef & Russet Potato Recipe</li><li>another fresh diet — JustFoodforDogs Chicken & White Rice Recipe.</li></ol><p>The two fresh diets contained minimally processed beef, chicken, broccoli, rice, carrots, and various food chunks in a canine casserole of sorts. </p><p>(One can't help but think how hard it would be to get finicky cats to test new diets. As if.)</p><p>Senior author <a href="https://ansc.illinois.edu/directory/ksswanso" target="_blank" rel="noopener noreferrer">Kelly S. Swanson</a> of U of I's Department of Animal Sciences and the Division of Nutritional Sciences, was a bit surprised at how much better dogs did on people food than even refrigerated dog chow. "Based on past research we've conducted I'm not surprised with the results when feeding human-grade compared to an extruded dry diet," he <a href="https://aces.illinois.edu/news/feed-fido-fresh-human-grade-dog-food-scoop-less-poop" target="_blank">says</a>, adding, "However, I did not expect to see how well the human-grade fresh food performed, even compared to a fresh commercial processed brand."</p>Tracking the effect of each diet
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3NjY1NTgyOX0.AdyMb8OEcjCD6iWYnXjToDmcnjfTSn-0-dfG96SIpUA/img.jpg?width=980" id="da892" class="rm-shortcode" data-rm-shortcode-id="880d952420679aeccd1eaf32b5339810" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />Credit: Patryk Kosmider/Adobe Stock
<p>The researchers tracked the dogs' weights and analyzed the microbiota in their fecal matter.</p><p>It turned out that the dogs on kibble had to eat more to maintain their body weight. This resulted in their producing 1.5 to 2.9 times the amount of poop produced by dogs on the fresh diets.</p><p>Says Swanson, "This is consistent with a 2019 National Institute of Health study in humans that found people eating a fresh whole food diet consumed on average 500 less calories per day, and reported being more satisfied, than people eating a more processed diet."</p><p>Maybe even more interesting was the effect of fresh food on the gut biome. Though there remains much we don't yet know about microbiota, it was nonetheless the case that the microbial communities found in fresh-food poo was different.</p><p>"Because a healthy gut means a healthy mutt," says Swanson, "fecal microbial and metabolite profiles are important readouts of diet assessment. As we have shown in <a href="https://academic.oup.com/jas/article/92/9/3781/4702209#110855647" target="_blank">previous studies</a>, the fecal microbial communities of healthy dogs fed fresh diets were different than those fed kibble. These unique microbial profiles were likely due to differences in diet processing, ingredient source, and the concentration and type of dietary fibers, proteins, and fats that are known to influence what is digested by the dog and what reaches the colon for fermentation."</p>How did kibble take over canine diets?
<p>Historically, dogs ate scraps left over by humans. It has only been <a href="https://www.thefarmersdog.com/digest/the-history-of-commercial-pet-food-a-great-american-marketing-story/" target="_blank">since 1870</a>, with the arrival of the luxe Spratt's Meat Fibrine Dog Cakes—made from "the dried unsalted gelatinous parts of Prairie Beef", mmm—that commercial dog food began to take hold. Dog bone-shaped biscuits first appeared in 1907. Ken-L Ration dates from 1922. Kibble was first extruded in 1956. Pet food had become a great way to turn <a href="https://www.dogfoodadvisor.com/choosing-dog-food/animal-by-products/" target="_blank">human-food waste</a> into profit.</p><p>Commercial dog food became the norm for most household canines only after a massive marketing campaign led by a group of dog-food industry lobbyists called the Pet Food Institute in 1964. Over time, for most households, dog food was what dogs ate — what else? Human food? These days more than half of U.S. dogs are <a href="https://www.nytimes.com/2014/08/03/magazine/who-made-that-dog-biscuit.html" target="_blank">overweight or obese</a>, and certainly their diet is a factor.<span></span></p><p>We're not so special among animals after all. If something's healthy for us to eat—we're <em>not</em> looking at you, chocolate—maybe we should remember to share with our canine compatriots. Not from the table, though.</p>Your genetics influence how resilient you are to the cold
What makes some people more likely to shiver than others?
Some people just aren't bothered by the cold, no matter how low the temperature dips. And the reason for this may be in a person's genes.
Harvard study finds perfect blend of fruits and vegetables to lower risk of death
Eating veggies is good for you. Now we can stop debating how much we should eat.
- A massive new study confirms that five servings of fruit and veggies a day can lower the risk of death.
- The maximum benefit is found at two servings of fruit and three of veggies—anything more offers no extra benefit according to the researchers.
- Not all fruits and veggies are equal. Leafy greens are better for you than starchy corn and potatoes.
Cephalopod aces 'marshmallow test' designed for eager children
The famous cognition test was reworked for cuttlefish. They did better than expected.
