Saturday, August 24, 2019

Life within Ice

A beautiful shot of micro-penitentes on Mt Rainier near Seattle, WA as photographed by Mark Sanderson in 2006 ( CC3.0, license and original file and description here ). What I love about this image is the lack of anything familiar that could indicate the scale of the features - aside from the notes from the photographer. They could be cm across or km! This is a familiar feeling from looking at images that come back from spacecraft that challenge our preconceptions. Today, PhD student Giang reflects on his recently published work trying to understand whether such textures could arise on Mars and if so, how big would they be and in what directions would they be orientated? Such models are needed to help us interpret what we see.

By Giang Nguyen

Perhaps it’s a mental coping mechanism from the summer heat, but I’ve been thinking a lot about ice. The behaviour of water ice across the solar system is studied by many people in the PVL group, and I am no exception. I’ve been looking at how water affects the atmosphere since my undergrad where I studied terrestrial weather systems. Later, the work for my Master’s consisted of surveying the icy conditions of the Martian north polar cap to look for surface-atmosphere interaction. Finally, with my PhD well on its way, I’ve been tasked with studying the atmospheric conditions of possible icy worlds beyond our solar system.

As you might guess, water is somewhat an important volatile for the propagation of life on Earth. Since there isn’t another planetary body within the solar system that is like Earth, it is helpful to look at the most extreme conditions Earth has to offer for clues. From my introductory paragraph, you’re probably thinking that I’m going to talk about Earth’s arctic polar conditions but that won’t be the case. The geography of interest here is actually high-altitude deserts, chiefly the Atacama desert located within South America’s Andes mountains.

Wednesday, August 7, 2019

Seasonally Shadowed Regions on the Moon: Adding Greater Intrigue to the Lunar Poles



This week, Jacob Kloos, a PhD Student here at PVL discusses exciting new research he has just published in the Journal of Geophysical Research, Planets. In his work, Jake found that the famous permanently shadowed regions (PSRs) are surrounded by seasonally shadowed regions (SSRs) which turn out to have important implications for the lunar water exosphere and the amount of water available in different locations at different times of the year - they're not what you would expect! Above, one of the key findings of the research: maps of the lunar poles showing these SSRs.

By Jacob Kloos

Over the past few decades, the north and south polar regions of Earth’s moon have garnered much attention within the field of planetary science. In addition to becoming prime targets for robotic and human exploration, the lunar poles have also been the subject of an increasing number of scientific studies. What makes these areas so intriguing for science and exploration? The answer lies in their unique illumination environments.

Unlike the Earth which rotates on an axis tilted 23.5 degrees from the ecliptic normal, the spin axis of the Moon is tilted only 1.5 degrees, ensuring that the Sun is always near the horizon for an observer at one of the poles. The low axial tilt of the Moon, coupled with its heavily heavily cratered surface, produce complex illumination patterns at high latitudes, giving rise to extremes in both sunlight and shadow: areas that are high in elevation may experience near-continuous sunlight, while some low-lying basins are in permanent shadow. Although no regions on the Moon (or indeed in the solar system) have yet been discovered which can claim the ethereal title of “peaks of eternal light,” some regions, like the rim of Shackleton crater near the South Pole, remain bathed in sunlight for 80-90% of the year. Such areas are attractive sites to send a solar-powered rover.

The permanently shadowed regions (PSRs), which are in many cases directly adjacent to the near-continuously illuminated regions, are not only interesting from an exploration perspective, but also from a scientific perspective. As a direct consequence of not receiving direct sunlight, and because the Moon lacks a substantial atmosphere to sequester and transport heat, permanently shadowed regions are among the coldest places in the solar system, enabling them to trap and store volatiles such as water across geologic periods of time. These volatile deposits constitute a valuable resource for scientific study as they would be well preserved and largely protected from chemical weathering; as such they could provide valuable insight into the delivery of water to the inner solar system - in particular to the Earth-Moon system. As for exploration, water could be extracted in-situ by future explorers, and could provide a source of potable drinking water, breathable air or perhaps even rocket fuel if broken down into its constituent components.

Friday, August 2, 2019

50th Anniversary of the Moon Landing Blog Post

This week, PVL Undergraduate Researcher Ariella Sapers reflects on a significant anniversary for space exploration: the 50th anniversary of the Apollo Moon landings. Above, a photo of a plaque like the one left on the lunar surface by Apollo 11. And yes, folks, that is Richard Nixon's signature on the bottom (to my knowledge the only politician whose name is written on a monument off the Earth) - it took the efforts of three different administrations to pull off this event.

By Ariella Sapers

With the 50th anniversary of the Moon landing just passing, I thought it was only appropriate to dedicate a blog all about the event and the celebrations that occurred here at York University!

On July 20th 1969, three brave men, Neil Armstrong, Edwin “Buzz’’ Aldrin, and Michael Collins took a leap of faith as part of NASA’s Apollo 11 lunar mission and headed to the moon. The Apollo Lunar Module, The Eagle, landed on the moon at 20:17 UTC in which Neil Armstrong became the first person to walk on the surface of the moon on July 21st at 02:56 UTC. With this walk, human beings had officially walked on the surface of a planetary body that wasn’t Earth.