A crew of NASA retirees, young hackers, and seasoned engineers has an audacious dream to rescue an abandoned spacecraft that has been coasting, unwanted and unloved, through the solar system since the mid-1990s.
Originally known as the International Sun-Earth Explorer-3 (ISEE-3), the ship was launched in 1978 to study the stream of charged particles flowing from the sun. NASA retired the craft in 1997 and has pretty much ignored it ever since.
But in May, fans of the zombie ship reestablished contact with it—the first time that a private group has ever controlled a spacecraft beyond Earth's orbit. On Saturday, the team, funded by nearly $160,000 from crowdsourcing, will test the spacecraft's steering jets.
If all goes well, the jets will be restarted at the end of the month and the spacecraft coaxed out of its current solar orbit into an orbit around Earth. Aerospace engineer Dennis Wingo, CEO of aerospace firm Skycorp and one of the team leaders working on the project, explains.
Why rescue a spacecraft no one seems to want?
People were saying it was going to be impossible to do. Maybe it's a character defect I have, but when someone says it's impossible to do, I look to see if it's possible. At the same time, at my company, we want to build spacecraft. This is a really good way to train my guys, to give them experience on a real mission. We do it because it's cool, too.
What accomplishments did this spacecraft rack up before NASA abandoned it?
It went almost a million miles away from Earth in the direction of the sun. Its original mission was to look at the sun and provide data to scientists so they could better predict how the sun actually functions. It was the very first spacecraft to travel really, really close to a comet. It has these big booms on it that are almost 200 feet (61 meters) across from the tip of one to the tip of the other. It's rotating really fast with these really big antennas on it. So we just think it's a really cool spacecraft.
How long has it been silent?
In 1999, NASA actually got rid of the equipment it was using to talk to the spacecraft. After that NASA had no way to turn on the telemetry and listen to what it had to say.
If NASA discarded the communications equipment, how did you manage to speak to ISEE-3?
There's a company we're working with called Ettus Research, and they have a piece of hardware that has software that emulates all of the hardware equipment NASA used to have. We put that together so we could talk to [the spacecraft] in its language and actually receive the data in its language and read what the spacecraft actually says.
What was it like to hear back from the spacecraft for the first time in some 20 years?
Awesome. It's like, "Oh my god, this thing is still alive. This is way cool."
You were at the Arecibo Observatory in Puerto Rico for this project when an earthquake hit in May. One of your colleagues tweeted, "Dennis Wingo was up in the dome [of the radio telescope] when the earthquake hit... He doesn't need any more coffee today." What was that like?
We were sitting up on top of the telescope, 450 feet (137 meters) above the ground, when all of a sudden it started vibrating. Then it got stronger, and we go, "Oh, wow." I was taking a video at the time, and I turned the video off and grabbed onto something. I just figured holding on was the best course of action to take.
Why are you trying to move the spacecraft off its current path?
If we don't, it will not be captured into Earth orbit at all. There's [also] a non-zero probability of it hitting the moon. We have to find [the spacecraft's] position, and then we'll fire the thrusters, which will put us exactly on course for the orbit above the moon that we need.
If you can put it on the right path, will it miss the moon?
Yep. We didn't start on this project until April 12, so we didn't have much time. We have the added pressure that as the spacecraft gets closer to the moon, it gets harder to change its course. So we've got to change the course in the next few weeks, because if we don't there's not enough fuel in the spacecraft to change the course.
What's next for ISEE-3 if everything goes as you hope?
What we want to do is put it in a stable Earth orbit and turn the scientific instruments back on, and use that for education. We're going to stream the data over the web live so people can use it. This isn't something that just a few scientific principal investigators will use and write papers on. This is something for everybody to access and read the data.
What could go wrong?
We have absolutely no idea if the thrusters are going to work. They haven't been fired since Ronald Reagan was president. If all the fuel's leaked out or something like that, we'll just read the telemetry until it goes by the moon and goes off into deep space again, and we'll wish it good-bye.
This interview has been edited and condensed.