Astronomers have identified three ancient asteroids which they claim are among our Solar System's oldest objects.
According to them, these ancient asteroids are relatively unchanged since they formed some 4.55 billion years ago and are older than the oldest meteorites ever found on our planet Earth.
Lead astronomer Jessica Sunshine of the University of Maryland said, "We have identified asteroids that are not represented in our meteorite collection and which date from the earliest periods of the Solar System.
"These asteroids are prime candidates for future space missions that could collect and return samples to Earth providing a more detailed understanding of the solar system's first few millions of years."
Sunshine and her fellow researchers at City University of New York, the Smithsonian Institution and the University of Hawaii detected the asteroids using visible and infrared data collected from telescopes on Hawaii's Mauna Kea.
At the beginning of the Solar System, there was just a disk-shaped cloud of hot gas, the solar nebula. When gasses on edge of the early nebula began to cool, the first materials to condense into solid particles were rich in calcium, aluminium.
As the gasses cooled further, other materials also began to condense. Eventually the different types of solid particles clumped together to form the common building blocks of comets, asteroids, and planets.