Saturday, March 19, 2016

Let's Get Small

Click the arrow to watch a March 5, 2016 CBS News report on the St. Thomas More Cathedral School small satellite. You may be subjected to an ad first.

What's a satellite?

Check and you'll find several definitions.

In astronomy, it's “a natural body that revolves around a planet.” Earth's Moon is a satellite to the planet.

When we use the word, we tend to think of artificial satellites — “a device designed to be launched into orbit around the earth, another planet, the sun, etc.”

Until recently, we think of artificial satellites as very large.

Take for example TerreStar-1, the self-proclaimed largest commercial satellite ever built, launched by TerreStar Corporation in July 2009. It had a launch mass of about 15,000 pounds, or 7,000 kilograms.

TerreStar filed for bankruptcy in October 2010. According to one media report, “Analysts estimated the cost of the satellite, launch and insurance to exceed $500 million.”

But if you're willing to go small, you can launch your own satellite into space for a few thousand dollars.

St. Thomas More Cathedral School in Arlington, Virginia launched a “CubeSat” in December 2015 to the International Space Station. Called STMSat-1, it measures about 4 inches or 9 centimeters to the side. The device has a small camera that will transmit images every thirty seconds back to the school.

STMSat-1 cost the school about $50,000, partially funded by a NASA contest grant. According to a 2013 NASA article:

The pre-kindergarten and kindergarten classes conduct outreach. The first grade has mission operations, including building the antenna and operating the ground station. The second grade is responsible for earth observation, including operating the cameras and building the solar arrays. The third grade is writing the procedures, operating the asteroid detection camera and conducting system engineering including orbit determination. The fourth grade is creating the computer-aided design of the mechanical structure and performing environmental testing. The fifth grade is the communication team, responsible for the Ham radio transmissions of images from the CubeSat to the ground station and also the battery. The sixth grade is building the spacecraft bus including the power and flight computer. The seventh grade is making the 3D compass payload, which will determine the location and orientation of the satellite. The eighth grade just successfully conducted a high-altitude balloon test.

Small commercial satellites have been around since the 1980s. The United Kingdom company Surrey Satellite Technology launched its first smallsat in 1981. The 13th annual CubeSat Developer's Workshop will be held in April in San Luis Obispo, California. The 30th annual Small Satellite Conference will be held in August in Logan, Utah.

Since 2007, the National Science Foundation has funded university cubesat projects.

Stanford University's Space and Systems Development Laboratory “provides graduate students with a world-class education and research in the field of space system design, technology and operation.” According to their web site:

SSDL's Satellite Quick Research Testbed (SQUIRT) trains students in all aspects of the spacecraft design life cycle through hands-on work on real, student-engineered satellites — intended to be excellent examples of simple, fast, cheap, flexible and intelligent micro-satellite design, launched into orbit and operated from Stanford. SQUIRT also prepares students for participation in SSDL's advanced space research projects. Scientific and engineering partners in these projects include a variety of academic research centers, government laboratories and industrial corporations. SSDL's flagship satellites are SAPPHIRE and OPAL.

It's a boom era for the small satellite industry. According to an August 2015 Fortune magazine article:

Interest in small satellites — typically defined as those under 500 kilograms (1,100 pounds) — has grown over the years based on a number of factors working in tandem: The miniaturization of once-bulky satellite components, standardization of many satellite parts, and other factors have trimmed costs substantially. That has made the building, launching, and operation of “smallsat” constellations increasingly feasible.

In January, the Tauri Group published a study titled, Start-Up Space: Rising Investment in Commercial Space Ventures. They found that, “More venture capital ($1.8 billion) was invested in space in 2015 than in the prior 15 years, combined.”

The report stated that SpaceX is the first “NewSpace” company to reach a valuation of more than $1 billion. Tauri named small satellite company Planet Labs as potentially the next billion-dollar startup in the space industry.

A Planet Labs film promoting use of its earth-imaging satellites to monitor agriculture. Video source: Planet Labs YouTube channel.

Planet Labs is deploying a “flock” of Dove nanosatellites using the International Space Station. To quote from the NASA press release:

Commercial applications of the imagery include mapping, real estate and construction, and oil and gas monitoring. If a company has high-value, distributed assets that need regular monitoring, Flock 1 imagery can assist in this type of endeavor. For example, Flock 1 can supplement or replace the need for flying a helicopter over an oil pipeline to monitor for a leak, since the 28 Dove CubeSats can quickly collect the necessary imagery.

Anticipating the demand to launch small payloads, Kennedy Space Center in July 2015 dedicated Launch Pad 39C. According to the KSC Partnerships page, “Launch Pad 39C will serve as a multi-purpose site allowing companies to test vehicles and capabilities in the smaller class of rockets, making it more affordable for smaller companies to break into the commercial spaceflight market.”

In October, NASA awarded three Venture Class Launch Services contracts for companies to demonstrate small satellite launch capabilities. One company, Firefly Space Systems, already has committed to using Pad 39C as a launch site.

The July 17, 2015 dedication of Pad 39C. Video source: NASAKennedy YouTube channel.

Another contract winner, Virgin Galactic, plans to use a 747 with a booster under its left wing to launch small payloads. I wrote on February 9 about the Virgin Galactic partnership with Airbus to create a constellation of micro-satellites to function as a space-based Internet. The OneWeb partnership may build and launch its microsats from the Space Coast.

NASA continues to do its part to evolve smallsat technology.

Another passenger with STMSat-1 on that December 7 commercial cargo delivery to the ISS was the NASA Nodes swarm satellite experiment.

The Nodes mission, which consists of two CubeSats weighing just 4.5 pounds each and measuring 4 inches by 4 inches by 6.5 inches, will test new network capabilities for operating swarms of spacecraft in the future.

“The purpose of the Nodes demonstration is to test out the potential for using multiple, small, low-cost satellites to perform complex science missions,” said Andrew Petro, program executive for the Small Spacecraft Technology Program (SSTP) in the Space Technology Mission Directorate at NASA Headquarters in Washington.

A first for small satellites, Nodes will demonstrate the ability to receive and distribute commands in space from the ground in addition to periodically exchanging scientific data from their onboard radiation instruments. The satellites will be able to configure their data network autonomously by determining which spacecraft is best suited to communicate with the ground each day of the mission.

“The technologies demonstrated during this mission are important, as they will show that a network of satellites can be controlled without communicating to each satellite directly,” said Roger Hunter, program manager for SSTP at NASA’s Ames Research Center at Moffett Field, California. “Nodes will demonstrate inter-satellite communications and autonomous command and control; this will help enable future constellation command and control capabilities.”

The NASA project to test swarm satellite technology at the International Space Station. Video source: NASA's Ames Research Center YouTube channel.

The article concludes:

Networked swarms of small satellites will open new horizons in astronomy, Earth observation and solar physics. Their range of applications includes multi-satellite science missions, the formation of synthetic aperture radars for Earth sensing systems, as well as large aperture observatories for next-generation telescopes. They can also serve to collect science measurements distributed over space and time to study the Earth, the Earth’s magnetosphere, gravity field, and Earth-Sun interactions.

Researchers are already positing the notion of using a satellite swarm as a telescope. A 2010 Netherlands astronomy group wrote:

A logical next step would be to investigate possibilities to miniaturize the electronics and use very small satellites, perhaps even nano satellites with masses between 1-10 kg to build the radio telescope. The approach is to use a swarm of satellites to establish a virtual telescope to perform the astronomical task.

A generation of U.S. school students are learning right now how to deploy and operate small satellites in low Earth orbit. Their generation may be the one that first deploys a deep space swarm telescope, or uses a swarm of satellites to make a three-dimensional image of an asteroid ripe for harvesting.

“Satellite school” now has an entirely new meaning.

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