Monday, June 16, 2014


You would probably expect to see a hanger full of mad scientists and a lot of evil laughing going on, but alas you would find the ISEE-3 reboot team – a citizen group of engineers, scientists, engineers, and fans. They have all come together to support a mission that is no longer maintained by NASA.

ISEE-3 (International Sun/Earth Explorer-3) was launched was launched on August 12, 1978, into a heliocentric orbit. As a part of the cooperative program between the ESA and NASA, its purpose at the time was to study the interaction between the magnetic field of Earth and the solar wind. Then it was re-tasked in 1982.

With its new mission came a new moniker. It was now named the International Cometary Explorer (ICE). Its primary objective was to study the interaction between solar wind and a cometary atmosphere. An encounter with the comet Giacobini-Zinner followed. Next up in late March of 1986 the craft passed through the tail of the comet Halley.

But wait! Next up the ICE mission was updated to include a heliospheric mission; a mission where it investigated CMEs in coordination with ground observations and cosmic ray studies and also the Ulysses project for data analysis.

On May 5th of 1997 the ICE mission came to an end and NASA in 1991 donated the still in space craft to the Smithsonian Museum. In 1998 NASA ceased all communications with the spacecraft and even threw out its documentation.

But back to today. On August 10, 2014ISEE-3 should be “whipping around the moon”; or colliding with it, tough call. With donated radio-telescopes and research this “reboot team” has managed to find out how the probe works. Not only that, they even made two-way contact with the old spacecraft. Now they have hacked their way into control of the vehicle it is both awesome and worrisome. First they need to successfully navigate the spacecraft.

As it gets closer to its trip around the moon and it is in a place where both gravitations (the Earth and that of the Moon) are pulling at it. ISEE-3 will need more and more delta-v in order to change its trajectory and that equates to lots of energy and time.

Why time? The spacecraft’s battery went a longtime ago and also it has no computer(I know – hard to believe!) so it can’t just be programmed in advance. The many adjustments to its path need to be entered as needed – tedious work. And so the reboot team will adjust and adjust and adjust the path for three weeks. And when the ISEE-3 makes its swing around the dark side of the moon, it’s on its own.

For decades now the ISEE-3 has survived on solar power. When it makes goes behind the moon (for the whopping half hour it will spend in total darkness) the reboot team can’t guarantee that it will come out the other side. Forget that it no longer has a battery back-up, but with a quarter century or so of frayed and fried circuitry it could just lose power like a town in a black out except it never comes back.

Now should it survive August 10th – both the threat of crashing into the moon and the threat of power loss then there are decisions to be made.

Now what?

The reboot team hasn’t decided for sure, but right now there are only options. They could fire the engines the last few times in a direction that will send ISEE-3 back to its starting point of the first Lagrange point (a stable area where the combined gravitational pull of two large masses – ie. Earth & Moon, provide just the correct centripetal force required to remain in orbit.) Of course the problem with that is first of all stopping when its gets there and then maintaining a stable orbit as both require fuel. Besides, that space is already occupied by spacecraft far more advanced than ISEE-3.

So then where to send it? Either the boring trip of an endless back and forth between the moon and Earth or around 2018 there is a comet it could visit! The first wouldn’t give much data but the second, well that exciting!

I simply want to add how cool it is that NASA develops these spacecraft that live forever and  in this case a totally unaffiliated group (The Reboot Team)can keep it going! Awesome!


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