A type of very dark “dark matter,” which remains dark even when illuminated, has been brought back from Ryugu, a celestial body expected to explain the origins of Earth and life.
The Hayabusa-2 mission by JAXA (Japan Aerospace Exploration Agency) has returned a true treasure to Earth: a sample of strange material that reflects only 2% of the light shining on it, making it darker than any material on Earth.
According to Dr. Tory Yada from JAXA’s Institute of Space and Astronautical Science, one of the scientists involved in analyzing the “dark matter,” it has a high porosity of 46%, greater than any meteorite previously studied.
Special dark matter sample from Ryugu – (Photo: JAXA).
Meanwhile, Dr. Cédric Pilorget from the Institute of Spatial Astronomy (University of Paris – Saclay, France), a co-author, stated that they identified the sample’s composition using a special microscope capable of capturing images at different wavelengths in the visible and infrared spectra.
According to Sci-News, the research team determined that the primary component of the sample is a hydrated matrix, similar to clay, with numerous organic materials “embedded” within it. Some individual components adhered to the sample are made of different materials such as carbonates or volatile substances.
This indicates the heterogeneous microstructure of Ryugu: it is a much more complex celestial body than previously thought. Primarily, it remains a carbon chondrite meteorite, but it is darker, more porous, and more fragile.
This is a fascinating discovery because Ryugu is an ancient asteroid, dating back to the early days of the Solar System. Its composition may reflect the fundamental materials that formed the planets, as well as the organic compounds that could be the first seeds of life on Earth.
Ryugu is named after the Dragon Palace, an underwater palace in Japanese folklore. It is a type C near-Earth asteroid, discovered in May 1999. Ryugu has a diameter of about 900 meters and orbits the Sun in an elliptical path of 474 days, ranging from 0.96 to 141 astronomical units (1 astronomical unit is the distance from the Sun to Earth).
The study was recently published in Nature Astronomy.
