What do this
and this
have in common?
The first picture is of Lynchburg College’s 3.5-inch Questar telescope, a gift to the college from a long-time Board of Trustees member. For those who don’t know, Questar is to small telescopes as Mercedes-Benz is to automobiles: beautifully made, and they last forever. This one was manufactured in 1963.
The second picture is of a Dove CubeSat, manufactured by Planet Labs. CubeSats are designed to be a cheap way to get something into space. A 1U (one unit) CubeSat is ten centimeters on a side with a mass limit of one kilogram—the size and mass of one liter of water. The Dove is a 3U CubeSat, 10 x 10 x 34 centimeters.
What these two images have in common is the Questar telescope, although the one in the Dove is made of Invar, an iron-nickel alloy notable for its resistance to thermal expansion. This is especially important in the space environment, where instruments are alternately baked and frozen. The Lynchburg College instrument is made largely of aluminum.
The remarkably small size of this satellite is testimony to the huge advances in consumer electronics over the past twenty years. Most of its components are off the shelf: the electronics are essentially those of a smart phone and of a radio transmitter and receiver. The telescope has a high-resolution CCD camera at its focus, and the images it captures can be sent back to a relatively small radio dish on Earth. The picture below is of strawberry fields in Florida. Beatles fans will know why I picked this image.
You can view a gallery of such images here.
But…so what? There are lots of satellites taking pictures of the Earth. What makes Planet Labs the hot new company for venture capitalists? The relatively low cost of these CubeSats allows dozens of them to be launched into space on a single rocket, and two or three to be tucked away on supply missions to the International Space Station. With multiple satellites in multiple orbits, the ultimate goal is to image the entire Earth every single day. This would take between 150 and 200 Doves in orbit; currently there are 71.
What would this let us track?
• River flooding
• Forest logging
• Road building in cities
• Forest fires
• Agricultural productivity
• Environmental compliance
• Commercial mapping
• Effects of climate change
• Snowmelt timing
…all in real time.
More and more, we are seeing private companies move into areas previously occupied only by national space agencies like NASA. It is the investment of government into something that doesn’t initially turn a profit, however, which made today’s space business viable. The founders of Planet Labs were all working at various NASA facilities before they founded their company. The director of the Ames Research Center in California (where several of them worked) said it very well: “Applying Silicon Valley to aerospace is the most revolutionary thing that’s happened probably since Goddard built his rocket. It’s not surprising that it started here. But it’s spreading.”
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