November 11, 2008, 4:36 PM — "Take care of that beautiful blue marble out there in space, our home planet. I'll be keeping an eye from here."
Those were among the last words posted by NASA officials identified as the Phoenix Mars Lander on Twitter. Personnel at NASA's Jet Propulsion Lab have been posting in the voice of the Mars Lander since May 25, when it touched down on the Red Planet during what mission control at the space agency described as "seven minutes of terror."
The latest posts from the Lander - which NASA announced Monday had stopped communicating due to a lack of sunlight that's needed to power the batteries that run the Lander's instruments - were markedly different from the jubilant messages posted just after the Mars landing.
The Lander's Tweets then included:
- "The parachute is open!!
- "Come on Rocketssssss!!!"
- "I've landed !!!!!"
- "Cheers! Tears! I'm here!"
The reflective messages posted over the last two weeks include:
- "In case we don't get this chance again, thank you all so much for the questions, comments & good wishes over the mission. It's been awesome."
- "The team has me on extreme "bed rest" to recharge power supply. There's cautious optimism about pulling out of this in a few days."
- "I'm resting a lot but still communicating with orbiters once per day. Still hoping to get a bit of strength back & maybe do more science."
- "I should stay well-preserved in this cold. I'll be humankind's monument here for centuries, eons, until future explorers come for me."
During the Lander's five-month stint on Mars, NASA posted 605 entries on Twitter , which included answers to questions posed by some of the almost 40,000 people who followed its updates on the site. This was the first time NASA had Twittered about a mission, and the Twitter posts grew into an invitation to be a guest blogger on tech blog Gizmodo, where the Mars Lander posted a farewell blog Monday. "If you are reading this, then my mission is probably over," the Gizmodo post noted. "This final entry is one that I asked be posted after my mission team announces they've lost contact with me. Today is that day and I must say good-bye, but I do it in triumph and not in grief.
The post went on to note that the Lander will hunker down and brave the long and cold autumn and winter on Mars , where the temperatures will reach minus 199 degrees Fahrenheit and a polar cap of carbon dioxide ice will grow around it to form an icy tomb.
The next Martian summer solstice - when maximum sunlight would hit the lander's solar arrays will be May 13, 2010.
"That's a long time away," the post continued. "And it's one of the reasons there isn't much hope that I'll ever contact home again. Scientists will be releasing findings based on my data for months, possibly years, to come and today's children will read of my discoveries in their textbooks. Engineers will use my experience during landing and surface operations to aid in designing future robotic missions."
The post ended with: "So long Earth. I'll be here to greet the next explorers to arrive, be they robot or human."