The European Space Agency (ESA) has selected the first of two cubesats to be deployed aboard the Ramses spacecraft. Its target will be the asteroid Apophis.
Apophis was discovered in 2004. Its diameter is about 340 meters. On April 13, 2029, it will make a close flyby of the Earth, passing at a distance of 32,000 km from its surface (i.e., inside the orbits of geostationary satellites). At that point, the asteroid will be visible in the sky with the naked eye over much of Europe and Africa, as well as parts of Asia.
Scientists estimate that objects the size of Apophis approach the Earth at such a short distance on average only once every 5000-10000 years. No wonder Apophis’ visit has gotten so much attention. Projects for missions to the asteroid are currently being developed by a number of countries and private companies. Last year, ESA joined them, announcing its intention to launch its own vehicle called Ramses. It will have to study how the approach to our planet will affect Apophis. This data will be useful in developing a method that humanity could use to determine the structure of a potentially dangerous asteroid and assess how best to deflect it away from Earth.
Since developing an interplanetary mission is a complex and time-consuming process, in order to speed things up, ESA has decided to use as the basis for Ramses the architecture of the Hera probe, which is currently holding on to the double asteroid Didymos. It has two cubesats on board that will have to assist in the study of the body. Similarly, the Ramses will also get the opportunity to take two fellow Cubesats with them.
ESA recently approved the design of the first of them. The vehicle will be built by Tyvak and will be equipped with a dust analyzer and low-frequency radar. A dust analyzer will examine material that could be ejected from Apophis’ surface by phenomena such as landslides, and radar will provide a detailed look at the asteroid’s internal structure. As for the mission’s second cubesat, engineers are considering turning it into a descent vehicle. This will allow direct study of the surface of Apophis.
It is worth noting that formally, the Ramses mission has not received final approval yet. It is expected to be received at the November 2025 ESA Ministerial Council meeting.
According to ESA
