Smooth Patch Beneath Phoenix has Changed

Join Our Community of Science Lovers!

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

A patch of shiny material visible beneath NASA's Phoenix Mars Lander dubbed "Snow Queen" underwent a striking change in appearance sometime between mid-June and mid-July, the space agency announced today. Now visible are cracks up to about four inches (10 centimeters) in length, a pebble less than one third inch (seven millimeters) in size, and a subtle change in the surface's smooth texture—none of which were seen during the first 20 sols (Martian days) of the mission, Phoenix co-investigator Mike Mellon of the University of Colorado at Boulder said in a statement. The changes call to mind the presumed ice specks that Phoenix observed sublimating (or vaporizing) from trenches dug near the craft. Phoenix got its first gander at Snow Queen on May 31 in what was cautiously described as possible ice exposed by thruster exhaust during landing six days earlier. The Phoenix team discovered the new changes when it checked on Snow Queen on July 9 after last viewing it on June 15. Mellon said the cracks could have formed from repeated expansion and contraction of the surface, or that the exposed layer simply shrank and cracked or that sublimating ice slowly revealed cracks underneath. The small pebble might have broken free of the surface or fallen from somewhere else, he said. Stay tuned for further changes.

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American