The International Space Station is often used to deploy small satellites, a low-cost way to test technology and science techniques in space.
On board this time, for deployment later this summer, are…
The ‘Rabbit’ in the RainCube
As its name suggests, RainCube will use radar to measure rain and snowfall. CubeSats are measured in increments of 1U (A CubeSat unit, or 1U, is roughly equivalent to a 4-inch box, or 10x10x10 centimeters). The RainCube antenna has to be small enough to be crammed into a 1.5U container; the entire satellite is about as big as a cereal box.
“It’s like pulling a rabbit out of a hat,” said Nacer Chahat, a specialist in antenna design at our Jet Propulsion Laboratory. “Shrinking the size of the radar is a challenge for us. As space engineers, we usually have lots of volume, so building antennas packed into a small volume isn’t something we’re trained to do.”
That small antenna will deploy in space, like an upside-down umbrella. To maintain its small size, the antenna relies on the high-frequency Ka-band wavelength – good for profiling rain and snow. Ka-band also allows for an exponential increase in sending data over long distances, making it the perfect tool for telecommunications.
TEMPEST-D millimeter-wave observations have the ability to penetrate into clouds to where precipitation initiation occurs. By measuring the evolution of clouds from the moment of the onset of precipitation, a future TEMPEST constellation mission could improve weather forecasting and improve our understanding of cloud processes, essential to understanding climate change.
Cutting Through the Noise
CubeRRT, also the size of a cereal box, will space test a small component designed to detect and filter radio frequency interference (RFI). RFI is everywhere, from cellphones, radio and TV transmissions, satellite broadcasts and other sources. You probably recognize it as that annoying static when you can’t seem to get your favorite radio station to come in clearly because another station is nearby on the dial.
The same interference that causes radio static also affects the quality of data that instruments like microwave radiometers collect. As the number of RFI-causing devices increases globally, our satellite instruments – specifically, microwave radiometers that gather data on soil moisture, meteorology, climate and more – will be more challenged in collecting high-quality data.
That’s where CubeSat Radiometer Radio frequency interference Technology (CubeRRT) comes in. The small satellite will be carrying a new technology to detect and filter any RFI the satellite encounters in real-time from space. This will reduce the amount of data that needs to be transmitted back to Earth – increasing the quality of important weather and climate measurements.
Searching the Halo of the Milky Way
Did you know that we’re still looking for half of the normal matter that makes up the universe? Scientists have taken a census of all the stars, galaxies and clusters of galaxies — and we’re coming up short, based on what we know about the early days of the cosmos.
That missing matter might be hiding in tendrils of hot gas between galaxies. Or it might be in the halos of hot gas around individual galaxies like our own Milky Way. But if it’s there, why haven’t we seen it? It could be that it’s so hot that it glows in a spectrum of X-rays we haven’t looked at before.
Image Credit: Blue Canyon Technologies
Enter HaloSat. Led by the University of Iowa, HaloSat will search the halo of the Milky Way for the emissions oxygen gives off at these very high temperatures. Most other X-ray satellites look at narrow patches of the sky and at individual sources. HaloSat will look at large swaths of the sky at a time, which will help us figure out the geometry of the halo — whether it surrounds the galaxy more like a fried egg or a sphere. Knowing the halo’s shape will in turn help us figure out the mass, which may help us discover if the universe’s missing matter is in galactic halos.
CubeSats for All
Small satellites benefit Earth and its people (us!) in multiple ways. From Earth imaging satellites that help meteorologists to predict storm strengths and direction, to satellites that focus on technology demonstrations to help determine what materials function best in a microgravity environment, the science enabled by CubeSats is diverse.
They are also a pathway to space science for students. Our CubeSat Launch initiative (CSLI) provides access to space for small satellites developed by our Centers and programs, educational institutions and nonprofit organizations. Since the program began, more than 50 educational CubeSats have flown. In 2016, students built the first CubeSat deployed into space by an elementary school.