As space exploration goes, we can do quite a bit within our own Solar System. We can land people on the Moon, rovers on Mars, and put satellites in orbit around the inner and outer planets. We even have the means of placing astronauts on Mars, presumably. But the cost are still prohibitively high, and when it comes to reaching distant celestial bodies, we remain pretty powerless.
Hence the new “space penetrator” program being contemplated by the European Space Agency. Basically, this amounts to a space missile that is fired in the direction of a celestial body, and which delivers a payload of sensors and equipment upon arrival on the surface. Classified as a “hard lander”, this program has been under development for ten years and offers many advantages over the standard soft lander.
For starters, a soft lander not only has to slow down before landing (which requires rockets and a payload of fuel), but has to be built to land rather than just crash into the ground. And if a soft lander wants to collect subsurface samples or conduct readings, it requires additional equipment to drill and scoop. By contrast, a penetrator can simply smash through a planet’s surface layer, and requires no additional fuel or landing gears.
Of course, a space penetrator also comes with its share of issues, like ensuring that its payload survives the hard landing. This requires that a special spring mechanism be included in the outer shell that cushions the payload from impact. This “suspension system” is made out of Torlon polymer, which is able to provide a 2mm gap of insulation during a high deceleration. A retrorocket will be employed in order to soften the blow a bit as well.
In order to rest the impact, the designers who built the steel penetrator fired it directly into a 10-ton block of ice. The missile traveled at 340m/s, just under the speed of sound, and turned the block into powder. But the penetrator’s casing and internal instruments remained intact and functional. Thanks to onboard sensors, the test impact will provide the developers of the missile, Rapid Space Technologies, with more information.
The space penetrator is intended to do more than just collect subsurface soil samples. Once in use, it will also help look for alien life by busting through icy surfaces, such as on Jupiter’s famous moon Europa. For years, scientists have suspected that the planet may support aquatic life beneath its icy surface. With the help of radio signals, the on-board sensors could send information up to an orbiting satellite, which could in turn relay that information back to Earth.
The European Space Agency has funded the project, but has not yet decided if it would ultimately use the space penetrator. Currently, the system isn’t designed to be launched from Earth, but rather a satellite or spaceship. There’s no telling if it will be used anytime soon, but it does present scientists and astronomers with an viable option for future interstellar exploration.
And there is huge potential as far as the exploration of Europa is concerned. Ever since it was postulated that subsurface oceans exist there – ones that are warm enough to support life – the Jovian moon has served as a source of inspiration for astronomers and science fiction writers alike. I for one am interested to see what resides underneath all that ice, provided we don’t disturb it too much!
And of course, there’s a video of the space penetrator test taking place. Check it out: