• NASA/JPL/University of Arizona

Another spectacular shot of a dune field from the UA Lunar and Planetary Lab's HiRISE aboard the Mars Reconnaissance Orbiter. Find the latest images here.

Speaking of the Lunar and Planetary Lab: You can join the LPL gang for an open house up on Mount Lemmon later this month where you'll be able to meet the scientists, see HiRISE images and check out the Catalina Observatories.

Details from LPL:

On Saturday, May 22, 2010, the University of Arizona's Lunar and Planetary Laboratory (LPL) is hosting a public open-day

at the Catalina Observatories, located on the summit of Mt. Lemmon, from noon to 6 p.m. This is one of several special events held throughout this year in recognition of LPL's 50th anniversary.

To sign up, visit http://www.lpl.arizona.edu/forms/openday/ or call 520-621-2828. Space is limited and reservations close on May 14 or when capacity is reached.

In addition to tours of the Mt. Lemmon telescopes, there will be hands-on displays of meteorites, exhibits depicting the development of astronomy in the Catalinas, the latest images from the UA HiRISE camera currently orbiting Mars, and solar viewing demonstrations. Because Mt. Lemmon is also an important natural laboratory, the open-day will include talks and demonstrations from the Arizona Geological Survey, the UA Laboratory of Tree Ring Research, and the Hummingbird Monitoring Network. There will even be something for history buffs, with a guided walking tour of the defunct Air Force Station, hosted by a veteran radar officer.

"This is a rare opportunity for Tucsonans to escape the onset of summer heat and see what goes on almost every clear night just a few miles north and thousands of feet above the city," said Ed Beshore, director of the Catalina Sky Survey (http://www.lpl.arizona.edu/css/) and one of the event's organizers. "Attendees will see demonstrations of the Catalina Sky Survey's operations, but will also get a chance to experience the wonderful natural laboratory we have here."