ESA CubeSat will probe asteroid with radar as part of Hera mission

ESA CubeSat will probe asteroid with radar as part of Hera mission
by Clarence Oxford
Paris (ESA) Mar 28, 2024

The European Space Agency (ESA) has embarked on a groundbreaking mission with the unveiling of the Juventas CubeSat, a compact spacecraft integral to the Hera mission aimed at exploring the Didymos binary asteroid system. This pioneering endeavor will mark the first radar investigation within an asteroid, focusing on the Dimorphos moonlet, comparable in size to the Great Pyramid.

Michael Kueppers, ESA's Hera project scientist, highlights the mission's significance, stating, "Today's asteroids are remnants from the dawn of our Solar System. Understanding their internal structure is crucial for insights into Solar System evolution and enhancing planetary defense strategies."

The Juventas CubeSat, a minuscule satellite measuring 37x23x10 cm, was developed by Luxembourg's GomSpace. Unlike typical CubeSats destined for Earth orbit, Juventas is designed for deep space missions, requiring advanced navigation systems to autonomously navigate around asteroids.

ESA's Hera mission, scheduled for launch in October 2024, aims to closely examine the aftermath of the DART mission's impact on Dimorphos, which altered its orbit around the larger Didymos asteroid. Hera will study the crater left by DART, as well as the mass and composition of both Dimorphos and Didymos, with Juventas and the Milani hyperspectral mission CubeSat playing pivotal roles.

Juventas is equipped with the smallest radar system ever deployed in space, developed by a consortium including France's Institut de Planetologie et d'Astrophysique de Grenoble and Technical University Dresden. The radar, capable of generating 3D images of Dimorphos' interior, will transmit signals via four 1.5-meter-long antennas, provided by Astronika in Poland.

"The Juventas Radar instrument offers the science community unprecedented insight into asteroid composition," said Jan Persson, Juventas project lead at GomSpace. Managing the radar's heat generation within the CubeSat's confines posed a significant challenge, now overcome by GomSpace's thermal design team.

Equipped with a suite of navigational and data-sharing instruments, Juventas will enter a Self-stabilised Terminator Orbit around Didymos, utilizing solar radiation pressure for stabilization. Following its radar survey, Juventas aims to land on Dimorphos to deploy the GRASS gravimeter, developed by the Royal Observatory of Belgium and Spain's EMXYS, marking the first direct gravity measurements on an asteroid's surface.

As the mission progresses, both Juventas and Milani CubeSats are undergoing comprehensive testing at ESA's ESTEC Test Centre in the Netherlands, ensuring their readiness for this unprecedented journey into the heart of an asteroid.