Today is a critical day for the Mars probe containing a high-resolution camera developed and built by UA scientists as it enters Martian orbit.

The public is welcome to attend the Mars Watch party today in honor of the Mars Reconnaissance Orbiter, which is expected to reach the Red Planet sometime this afternoon.

UA scientists and leaders of the High-Resolution Imagine Science Experiment project will be on hand to give a presentation and field questions, said Alfred McEwen, HiRISE team leader.

The UA’s HiRISE camera is aboard the orbiter and is expected to map the surface of Mars.

Today is important for the orbiter, as it will fire its engine thrusters to put itself into the Martian orbit, McEwen said.

“”We have to get into orbit successfully or nothing else matters,”” said McEwen, who is also a professor in the Lunar and Planetary Laboratory.

Loretta McKibben, information specialist coordinator for the LPL, explained why members of the UA community have their eyes on the skies.

“”It’s personal here at the UA because the high-resolution camera is based at the LPL,”” McKibben said.

The HiRISE camera cost $60 million to develop and build and is the most powerful camera to leave the earth’s orbit, McKibben said.

The camera is expected to take its first pictures of the Red Planet sometime after Sunday, McEwen said.

After taking the first few pictures, the orbiter will begin a 6-month period that will allow the craft to ease into Martin orbit. In September, the orbiter will begin photographing the surface, McKibben said.

The Mars mission is important because the camera will scout landing sites for future expeditions, including another UA-based endeavor called the Phoenix Mission, McKibben said.

In addition to the presentation, attendees will be able to watch live mission coverage from NASA’s Jet Propulsion Laboratory.

The party will be held in Room 308 of the Kuiper Space Sciences building from 1 p.m. to 4 p.m. and is free and open to the public.