Scientists have developed new funky-looking cups crafted from a 3D printed transparent polymer that could allow astronauts on the International Space Station (ISS) to enjoy an aromatic cup of coffee.
Astronauts are accustomed to drinking beverages from bags due to safety concerns over spillage.
Their responses when testing out the new cups ranged from "Hey, you can smell the coffee," to "This is eerily like drinking on Earth."
The cups, six in number, elicit happy eruptions of laughter because the astronauts readily confess they had not expected it to work.
Last year, Italy sent an espresso machine up to the ISS which inspired the researchers to study the related strange fluids phenomena in low gravity - such as espresso crema formation and settling, capillary interfaces, and containment of potentially hazardous drinks within a spacecraft.
To do this, the researchers designed a cup that exploits surface tension as opposed to gravity.
The cup works so well that the crew is able to cruise around, do flips, and even toss them back and forth - while drinking beverages such as fruit juice, fruit smoothies and coffee, the researchers said.
"Wetting conditions and the cup's special geometry create a capillary pressure gradient that drives the liquid forward toward the face of the drinker," said Mark Weislogel, a professor of mechanical engineering at Portland State University in US.
Unlike drinking a beverage from a bag, "your nose is closer to the beverage, which makes it easier to actually smell it while drinking," Weislogel said.
"An astronaut can drain the cup in sips or one long gulp in much the same manner as on Earth, without tipping their head, without gravity," he said.
"It's a stable situation - even though drinking scalding liquids from open containers while aboard the International Space Station is generally considered a safety concern," he said.
Of the six cups currently aboard the Space Station, five hold 150ml, while the sixth is a 60ml demitasse specifically intended for espresso.
The cups are complexly shaped and demonstrate that specific control of liquids can be maintained in low-gravity environments - but with completely different fluidics principles at play than on Earth.
