Looking into the endless darkness of space, it is easy to imagine the solar system as an empty void. But in the inner micrometroids of the solar system, tiny particles of cosmic dust, invisible to the naked eye, fly around the Earth at a speed exceeding 40,000 miles per hour. This poses a potential danger to the spacecraft that we put into orbit for space exploration. But how big a problem can microscopic dust be?
Researchers from NASA and the European Space Agency (ESA) wanted to find out. Use of a space-borne laser interferometer (LISA) rangeror the low-pass filter, which operated in orbit between January 2016 and July 2017, the group conducted a kind of research, during which it became clear how often their spacecraft fell under cosmic dust.
A study published in the Astrophysical Journal in September details 54 collisions with an LPF spacecraft. In fact, it was a technical demonstration – the equipment included in the LPF should be used in a fully functional LISA observatory. The main objective of the LPF was to show that the technology on board can be used for a full-fledged mission in the future. However, prior to launch, the researchers realized that the spacecraft’s unique sensitive instruments could be used to detect very small hits.
This is because every time the low-pass filter gets hit, small engines help him adjust the course. A study of these tiny course corrections revealed what happened and with what force. Researchers had access to 4,348 hours of LPF data for analysis and created a complete dataset of micrometeroid collisions with a spacecraft.
Then, by modeling the effects on the low-pass filter, the researchers were able to determine where the micrometeroids might come from. Previous studies of cosmic dust in this area of the solar system have shown that most of it comes from short-period comets, such as 67P / Churyumov-Gerasimenko, whose orbits are controlled by the gas giant Jupiter (comets of the Jupiter family). The “comet crumbs” that encountered the low-pass filter corresponded to these studies, with most of the effects coming from comets of the Jupiter family, and a smaller contribution from comets with a longer period.
In 2034, ESA will launch the development of the low-pass filter, a set of three spacecraft located in a triangle, allowing astronomers to hunt for gravitational waves with unprecedented accuracy. This will be a great blessing for astronomers studying extreme cosmological phenomena such as black hole fusion on the other side of the universe, but the low-pass filter has shown that next-generation instruments will also be useful for conducting experiments much closer to home.