The spacecraft New Horizons is on schedule to get a good view of Pluto on July 14th 2015.
We should soon have some measurements that will help determine how much of the icy planet is made up of water. On board New Horizons are instruments like Ralph, Alice, Rex, and Lorri. The requirements for these devices are that they need to be small, lightweight, powerful and robust, which sounds a lot like the specifications we desire for our field instruments on earth. There will be trickle down of these technologies for visible and infrared spectrometry and thermal mapping; UV spectrometry; Passive radiometry; and reconnaissance imaging into devices that will enable us to measure more parameters with greater reliability and resolution than ever before in our own watersheds.
There is a lot of interest in measuring water in space.
For one thing, water is the best predictor for the evolution of anything that we would recognize as life that there is. Furthermore, if we do eventually need to abandon our planet sometime in the future (say, because a big lump of space ice is on a collision course) we might want to stop by and replenish our supply 9 years into our journey (i.e. the time it took New Horizons to reach Pluto).
On board the International Space Station (ISS), astronauts have been recycling all of their water for many years with about 93% efficiency.
This seems pretty good but if you are losing 7% per cycle it won’t take too long before you might need to re-fresh the system with clean water, which on a long mission might mean stopping on Europa (a moon of Jupiter with about 3x as much water as there is on earth) or Pluto on your way out of the solar system.
Emerging technology for water recycling is already part of an integrated water management program in Singapore which includes rainwater capture, desalination and NEWater recycled water. NEWater is planned to meet up to 55% of Singapore’s future water demand. In a water-stressed future, it may be that we will only need to source water from the environment to offset the inefficiency in our water recycling program. In essence, we are already doing that but we currently need to supplement a recycling efficiency that is near 0%. Singapore’s current efficiency of 30% and the ISS efficiency of 93% are clear indications that we can do better.
Knowing how much water in our own watershed is important.
It is also interesting to know how much water there is 7.5 billion kilometers away. The technology for measurement is different, for now, but that is changing. If we can use our knowledge of water on earth to manage it a bit better, we may be able postpone the date that we need to leave the planet to take advantage of what we are learning about water in space.
Photo credit: NASA | “Recent Measurements of Pluto and Charon Obtained by New Horizons – A view of Pluto and Charon as they would appear if placed slightly above Earth’s surface and viewed from a great distance.”