One big technical challenge to solve if we ever want to live on Mars is how to make fuel. Sure, you can ship it from earth, but every pound of fuel requires 225 pound of fuel to deliver it - so that's not at all efficient.

But it turns out that Martian dirt can be turned into rocket fuel, which led to a different question: how do you dig in the low gravity of Mars?

Enter the space digger called RASSOR or Regolith Advanced Surface Systems Operations Robot.

Kurt W. Leucht wrote an article over at IEEE Spectrum to explain it all:

To dig, RASSOR uses two opposing bucket drums, each outfitted with several small and toothy digging scoops. When RASSOR’s bucket drums spin and the arms that hold them dip down, they scrape up just a small amount of regolith into each digging scoop as it drives slowly forward. This creates a shallow slot trench rather than a deep hole. These rotating and digging bucket drums are hollow inside, allowing them to collect and hold the excavated regolith. Another key feature of RASSOR is that, while digging, the bucket drums actually spin in opposite directions. This cancels out much of the digging forces and will allow RASSOR to excavate in low gravity.

See it in action in this video clip below:

Ryuji Tan adopted a stray cat named Busao, and now the cat has fallen in love ... with a space heater! Warm, quiet and completely loyal? Well, I understand completely cat. Good choice!

More of Busao the cat over at Instagram - via Grapee

More pics below:

This bagel shop wishes it was special! via u/noahsygg

How would you describe what scuba diving feels like to a disabled person, who's not physically capable of doing it? Through VR, of course!

Here's a neat story of the Amphibian Scuba Diving Simulator, a research project by Dhruv Jain of MIT Media Lab that let users experience diving underwater through virtual reality:

Most existing SCUBA diving simulations in virtual reality (VR) are limited to visual and aural displays. Amphibian advances the field of VR by engaging additional sensory modalities like thermoception (sense of temperature), equilibrioception (sense of balance), and proprioception (sense of spatial orientation and movement). Users lie on their torsos on a motion platform with outstretched arms and legs placed in a suspended harness.

An Oculus Rift head-mounted display and headphones allow them to see and hear the underwater environment. Various sensors are used to simulate buoyancy, drag, and temperature during the simulation. For example, Peltier modules attached to participants’ wrists through motion tracking gloves simulate temperature changes as they dive deeper into the water.

An inflatable airbag placed under the torso allows the user to control ascent or descent through breathing; inhaling makes the airbag inflate and exhaling makes it deflate. The virtual body rises up and down in sync. This is done using a gas sensor attached to a snorkel that measures the amount of air inhaled or exhaled.

Hate small talk? You're not alone ... turns out there's an entire country of people that don't like small talk: Finland.

Here's how Laura Studarus of BBC Travel describe what it's like there:

Small talk outside social situations between close friends is virtually non-existent. Interactions with baristas? Limited to the name of the coffee you want to order. Sitting, walking or standing in a way that requires acknowledging a stranger’s presence? Never. ... If you’re a foreigner, congratulations – you’re probably the loudest person on their often (voluntarily) silent public transport.

Finns even had to be taught how to chit chat when interacting with non-Finns:

As Tiina Latvala, a former English instructor in Sodankylä, Lapland, explained, part of her job was to introduce her young students to the concept of small talk.

“We had a practice where you had to pretend to meet someone for the first time,” Latvala said. “You had to pretend you were meeting at the cafe or on a bus and [that] you didn’t know each other and do a bit of chit chat. We had written on the whiteboard all the safe topics so they didn’t have to struggle with coming up with something to talk about. We brainstormed. They usually found it really difficult.”

For 28 years, John and Stella Chhan, husband and wife owner of a donut shop in Seal Beach, California, have been helping their customers.

But a few weeks ago, people started noticing that Stella had been absent from the donut shop ... Turns out, Stella had suffered an aneurysm, and that's when his customers sprang into action:

“Days went by and I just couldn’t get it out of my head,” said Dawn Caviola. “So I thought, if enough people would buy a dozen doughnuts every morning, he could close early and go be with his wife.” Caviola, “thinking out loud,” floated her idea on the neighborhood networking site Nextdoor early last week. The response was immediate and enthusiastic. Ever since, Chhan has sold out by noon – some three hours earlier than usual – freeing him to visit his wife at the rehabilitation facility. “We are so thankful,” said Chhan, 62, holding both hands over his heart.

Read the rest over at this heartwarming article by Susan Christian Goulding over at the Orange County Register.

(Photo: Paul Bersebach, Orange County Register/SCNG)

Whale watching is fine from a boat, but if you want to go whale counting, the best way is from space!

"Satellites have improved so much with their spatial resolution," explained Hannah Cubaynes, who is affiliated to both Cambridge University and BAS.

"For the first time we've been able to see features that are truly distinctive of whales, such as their flippers and flukes."

Read the rest over at the BBC.

(Image: DigitalGlobe)

When October Books, a small bookstore in Southampton, England, moved a few hundred feet down the street, they decided not to hire movers - instead, they called for volunteers to form a human conveyor belt!

NPR has the story:

Shoulder to shoulder, community members formed a line 500 feet long: from the stockroom of the old shop, down the sidewalk, and onto the shop floor of the new store.

Cafes brought cups of tea to the volunteers. People at bus stops joined in. Passersby asked what was happening, then joined the chain themselves.

(Photo: October Books)

In the 13th century, Marco Polo described present-day Azerbaijan as a "land of fire" - and for good reason: there are burning mountainsides with fires that didn't stop burning for thousands of years.

Maureen O'Hare of CNN Travel has the strange story of the eternal flame of Yanar Dag:

"This fire has burned 4,000 years and never stopped," says Aliyeva Rahila. "Even the rain coming here, snow, wind -- it never stops burning."

Ahead, tall flames dance restlessly across a 10-meter stretch of hillside, making a hot day even hotter.

This is Yanar Dag -- meaning "burning mountainside" -- on Azerbaijan's Absheron Peninsula, where Rahila works as a tour guide.

Read the rest over at CNN Travel.

(Photo: Maureen O'Hare/CNN)

Rennes, France-based urban artist Arthur-Louis Ignoré specialize in painting marvelous intricate geometric patterns. In this case, his canvas is a local basketball court.

More pics below:

The Dutch town of Spijkenisse has officially installed a "silly walks" pedestrian crossing, inspired by the classic Monty Python's 'The Ministry of Silly Walks' skit.

From the BBC:

Spijkenisse near Rotterdam has replaced the usual crossing sign by the town hall with one of a man with a bowler hat and briefcase flinging his leg high in the air, in emulation of John Cleese's performance from the 'Ministry of Silly Walks' sketch ...

Alderman Jan Willem Mijnans liked the [proposal to open a silly walks crossing], and agreed to preside at the not-very-formal opening of the rebranded crossing.

"It's nice to see people crossing the street with a smile on their face, and we hope lots of people will do so," he told the expectant crowds, before trying out his own silly walk.

(Image: SBS6)

First rule of daycare fight club is ... actually, there shouldn't be any rule of daycare fight club, because there shouldn't be a daycare fight club.

But that's exactly what happened back in 2016 in a daycare in St. Louis, when a heater broke and the teacher organized it in order to entertain the kids.

Fox5 News has the story:

The iPad video shows a fight in which the kids fall to the ground while a teacher kicks into the air in excitement. The only person who tries breaking it up is another preschooler, but he cannot stop one child from pounding the other's head into the floor. Merseal believes it only stopped because her older son texted her video. She called the director to stop it. She said her older son texted the video saying… “The daycare was making them fight, not helping them.”

Birds can see ultraviolet light, so how they see other birds can be very different from how we see them. For example, in the image above, what humans see is in the upper right-hand corner, whereas what birds see is the large picture on the left.

Nathan Chronister's Ultraviolet Bird Photography website has more neat examples.

Someone should tell West Virginians that smoking during pregnancy is bad for the health of the baby. According to the CDC, a staggering 25% of pregnant women in West Virginia smoked cigarette!

Why do West Virginians have the highest pregnant smokers? Perhaps it's because it has the most adult smokers of all the states.

Redditor academiaadvice graphed the data over the map of the United States.

Classical music can be comforting, even to elephants.

English classical pianist Paul Barton performs classical piece on the piano for the gentle giants at the ElephantsWorld sanctuary in Kanchanaburi, Thailand.

From CBS News:

It all started when he and his wife first discovered the sanctuary, Elephants World, online, Barton explains in a video. "We liked the sound of the place being a retirement center for old, injured and handicapped former logging and trekking elephants," Barton said. "So we paid them a visit. I wondered if these old rescue elephants might like to listen to some slow classical music."

Barton asked the employees at Elephants World if he could bring his piano and serenade the elephants some time, and they said yes. The first time Barton played his piano at Elephants World, a blind elephant that was eating his breakfast stopped in his tracks when he heard Beethoven for the first time.

"[He] was often in pain, and I like to think maybe the soothing the music gave him some comfort in the darkness," Barton said in the video.

The clip above is of Barton playing "Clair de Lune" by Debussy for an 80-year old blind female elephant named Ampan.

More video clips below: