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Ryan Ransom is a professor in the Physics and Astronomy Department at Ïã¸ÛÁùºÏ²Ê¿ª½±½á¹û²éѯ in Penticton. Ïã¸ÛÁùºÏ²Ê¿ª½±½á¹û²éѯLife asked him a few questions about the Penticton crater on Mars, and in general, how a day in the life in the crater would compare to life in its namesake of Penticton, B.C.

Q.  What are you teaching this term?
A.   In the winter semester, I teach the second parts of the first-year physics and astronomy courses in Penticton, and a second-year course called "History of the Universe" in Kelowna. In the fall semester, I teach a second-year course on Astrobiology in Kelowna.

Q.   have said that winter on the Penticton crater on Mars is pretty harsh. Would this be colder or warmer than what we experience?
A.  The temperature on Mars ranges from about -130 degrees Celsius on a winter night to about +20 degrees Celsius on a summer day. So, it’s certainly fair to say that a Martian winter is harsh. The temperature only tells part of the story, though. Mars' atmosphere is ~100 times thinner than Earth's. Even at +20 degrees Celsius, there is very little heat energy in Mars' atmosphere.

Q.  What does that mean from an astrophysical perspective?
A. In a broader context, we could say that Mars is just outside the Solar System's "habitable zone"; i.e., the region in a planetary system where the average temperature at the surface of a planet/moon is just right for liquid water (and thus life).

Q.  Seasonal ice makes it sound like there’s water on Mars, which is critical for lifeforms here on Earth. Any chance it’s the same kind of water?

A. The seasonal ice shown in this particular image is carbon dioxide ice (sometimes called "dry ice"), which at Mars' atmospheric pressure indicates that temperatures in the shaded regions of the crater are less than -110 degrees Celsius. There is also water ice on Mars. The water ice will melt in the sunlight on a summer day, but the liquid evaporates quickly under Mars' thin atmosphere. There's no life (or any organic molecules) on the surface of present-day Mars. Interestingly, Mars had a thicker atmosphere in the distant past, and there's excellent evidence that liquid water pooled and flowed on the Martian surface in the past. If there are still pools of liquid water under the surface, it is possible that these pools host life. The current lander mission, InSight, is probing the temperature a few meters under the surface.

Q.  How do planetary craters get their name?
A.  Great question. I can say, looking at the record, that the Penticton crater was named by the International Astronomical Union in 2008. In reading through Castanet's earlier article (Sept. 5, 2019), it seems the crater received its name because the city is affected by landslides. I reached out to my colleague JJ Kavelaars, a planetary scientist at NRC-DAO (which is DRAO's 'sister' institution in Victoria), for a little more insight.

Q.  Have you been to the Dominion Astrophysical Observatory in Penticton?
A.  The Dominion Radio Astrophysical Observatory (DRAO) is why I moved with my family to Penticton from Toronto. I had a post-doctoral position at DRAO in 2007-08, and still have a "visiting scientist" position at DRAO.

Q.  Could we see the Penticton crater on Mars, from Penticton?
A. The Penticton crater on Mars is just ~8 km across. The crater is unresolved to even our largest Earth-based telescopes. This speaks to the importance of space-based missions. We learn a great deal more about solar system objects when we get a close-up view. Mars has had 25 successful spacecraft visits, including 4 fly-bys, 12 orbiters, 5 landers and 4 rovers.

Q.  Any chance Martians are as cold as we are here in the Okanagan?
A. On Earth, we'd call them extremophiles – lifeforms that love the extremes.