Using a model similar to what meteorologists use to forecast weather on Earth and a computer simulation of the physics of evaporating ices, a new study, published in the journal Nature by York University Professor John Moores, Department of Earth & Space Science and Engineering at the Lassonde School of Engineering, has found evidence that snow and ice features previously only seen on Earth, have been spotted on Pluto.

“Penitentes” which are formed by erosion, are bowl-shaped depressions with spires around the edge and are several metres high.

The groundbreaking research, done in collaboration with researchers at NASA and Johns Hopkins University, indicates that these icy features may exist on other planets where environmental conditions are similar.

“The identification of the ridges of Tartarus Dorsa as Penitentes suggests that the presence of an atmosphere is necessary for the formation of penitentes, which would explain why they have not previously been seen on other airless icy satellites or dwarf planets,” says Moores.  “But exotic differences in the environment give rise to features with very different scales. This test of our terrestrial models for penitentes suggests that we may find these features elsewhere in the solar system, and in other solar systems, where the conditions are right.”

Moores, along with his York postgraduate fellow, Christina Smith; Anthony Toigo, at the Applied Physics Laboratory, Johns Hopkins University; and, NASA Research Astrophysicist, Scott D. Guzewich, at the Goddard Space Flight Center in Maryland, USA, compared their model to ridges on Pluto imaged by the New Horizons spacecraft in 2015. Pluto’s ridges are much larger – 500 metres tall and separated by three to five kilometres – as compared to their meter-sized earthly counterparts.

“This gargantuan size is predicted by the same theory that explains the formation of these features on Earth,” says Moores.  “In fact, we were able to match the size and separation, the direction of the ridges, as well as their age: three pieces of evidence that support our identification of these ridges as penitentes.”

Moores says though Pluto’s environment is very different from the Earth – it is much colder, the air much thinner, the sun much dimmer and the snow and ice on the surface are made from methane and nitrogen instead of water – the same laws of nature apply.  Both NASA and Johns Hopkins University were instrumental in the collaboration that led to this new finding.  Both provided background information on Pluto’s atmosphere using a model similar to what meteorologists use to forecast weather on Earth. This was one of the key ingredients in Moores’ own models of the penitentes, without which this discovery would not have been made.

Paper strips laced with sugar could be the sweetest solution discovered so far to kill E. coli in contaminated water. York University engineering Professor Sushanta Mitra says the “DipTreat” discovery will be instrumental in developing a new generation of inexpensive and portable water treatment devices. The discovery of the sweet solution holds promise for efforts underway to ensure water safety and will benefit human health in Canada and around the world.

DipTreat is the latest innovation by researchers working in the Lassonde School of Engineering’s Micro and Nano-scale Transport (MNT) Lab. The group has previously discovered new ways to detect E. coli in contaminated water using a Mobile Water Kit.

“Now with DipTreat, we have learned it will take less than two hours to fish, trap and kill E. coli in water,” says Mitra, who heads up the lab. “We were able to efficiently remove almost 90 per cent of bacteria by dipping the special paper strip, DipTreat, in contaminated water samples.”

While using porous paper strips to trap the bacterial cells, for killing, the researchers used an antimicrobial agent extracted from the seeds of moringa – commonly known as drumstick or horseradish tree. As a result, the DipTreat solution for water treatment uses only naturally available antimicrobial substances and sugar, with minimal environmental and health impact.

Currently, popular water treatment systems use silver nanoparticles and clays. The long-term impact of these systems on human health has yet to be fully understood, says Mitra. So far, DipTreat is effective for small quantities of water. For example, someone who is hiking can collect a container of water and use the paper strips to purify it before drinking.

“We expect this new approach to ‘fish’, ‘trap’, and ‘kill’ E.coli will seamlessly eliminate the harmful bacteria from water,” says Mitra. The discovery has potential for communities in the far north of Canada and in areas where water treatment in not in place or when facilities have been destroyed by conflict. Recognizing the global importance of water purification technology, UNICEF has invited Mitra to showcase his team’s work at a stakeholder meeting in Copenhagen on Nov. 22.

Published as a featured article in the latest issue of the Royal Society of Chemistry journal Environmental Science Water Research & Technology, the study is co-authored by Mitra, Saumyadeb Dasgupta and Naga Siva Gunda.