A Tiny, Inexpensive Satellite Will be Studying the Atmospheres of hot Jupiters

The Colorado Ultraviolet Transit Experiment (aptly nicknamed CUTE) is a new, NASA-funded mission that aims to study the atmospheres of massive, superheated exoplanets – known as hot Jupiters – around distant stars. The miniaturized satellite, built by the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder, is set to launch this Monday, September 27th on an Atlas V rocket.

Small-sized satellites like CUTE, known as CubeSats, are nothing new. They’ve long been a staple of collaborative university student projects, as cheap ways to get engineering experience in space. But lately, researchers have been pushing the boundaries of what CubeSats are capable of, putting them to the test with more and more ambitious projects. In 2018, for example, the first interplanetary CubeSats (MarCO-A and-B) left low earth orbit and traveled to Mars with NASA’s InSight lander, providing communications and telemetry for the lander as it descended towards the planet. CUTE, on the other hand, will remain in Earth orbit, but the scope of its ambition is equally lofty for such a small spacecraft.

Its primary mission is to understand the volatile physics around hot Jupiters. These enormous exoplanets have no analog in our solar system: they are similar in size to our gas giants, but orbit much closer to their stars, and can reach temperatures of over 7,800 degrees Fahrenheit.

CUTE principal investigator Kevin France explains that “because these planets are parked so close to their parent stars, they receive a tremendous amount of radiation.” That radiation heats the planets, causing their atmospheres to inflate and expand. Some of the gas eventually escapes and streams away from the planet.

University of Colorado graduate student Arika Egan leads installation of the CUTE CubeSat into the EFS dispenser system at Vandenberg Space Force Base on July 23, 2021. Credit: NASA / WFF

CUTE will spend its 7-month mission observing as many hot Jupiters as it can (10 at minimum), and measuring how quickly gas is escaping from them. Atmospheric escape is a process that happens to all planets, Earth included, but nothing like as quickly or on such large scales as on these hot Jupiters. Still, understanding how it works on these giants can help researchers understand how it works on rocky worlds too. If successful, the data CUTE gathers will be used to understand the processes of atmospheric escape on a wide range of different planet types.

This is the first time a NASA-funded CubeSat has been used to study exoplanets. LASP Director Daniel Baker is excited by what these tiny spacecraft can accomplish. “As little as a decade ago,” he said, “many in the space community expressed the opinion that CubeSat missions were little more than ‘toys. There was recognition that small spacecraft could be useful as teaching and training tools, but there was widespread skepticism that forefront science could be done with such small platforms. I am delighted that LASP and the University of Colorado have led the way in demonstrating that remarkable science can be done with small packages.”

The launch of CUTE from Vandenberg Air Force base in California can be watched live on September 27th, with liftoff planned for 2:12 PM EDT.

Learn More:

Daniel Strain, “New cereal box-sized satellite to explore alien planetsCU Boulder Today.

Featured Image: Artist impression of gases being blown away from KELT-9b, one of the hot Jupiters being studied by CUTE. Credit: LASP; NASA/JPL-Caltech/