Tomorrow’s the big day, when NASA’s Phoenix Mars Lander attempts to touch down after a nail-biting seven-minute descent through the atmosphere that has mission scientists on edge.

At a press conference at NASA’s Jet Propulsion Laboratory today, a few of those scientists described how they’re feeling with just over 24 hours until Phoenix enters Mars’ atmosphere.

“I’m really excited about being here,” JPL Phoenix mission manager Joe Guinn, adding, “I’m getting a real case of the heebie-jeebies now.”

Phoenix Project manager (also at JPL) Barry Goldstein said that he was starting to feel the nerves too, but that the meetings to plan for landing day, as well as lots of ice cream, are helping to keep the butterflies at bay.

Goldstein met with reporters during a tour of JPL mission control yesterday, which was nearly empty, except for a two or three engineers there just in case something went wrong. Tomorrow there, mission control will be packed with mission scientists, engineers, and a few VIPs.

With nerves likely to run high as the time for landing gets closer and closer, Goldstein will be using a long-time JPL nerve-killing tradition: passing out peanuts to the mission control crew.

The practice has apparently been in place since the Ranger missions to the moon. After the first few failed, those in mission control began to pop peanuts in an attempt to calm their nerves.

Phoenix will uphold this grand tradition, Goldstein said, adding, “I’ve already purchased the peanuts.”

So if you watch NASA TV tomorrow, look for peanuts making their way into the mouths of those in mission control.