... taken with the Spitzer Space Telescope imply that the disc consists of an inner asteroid belt analogue, a planetesimal belt between 100 and 310 AU and a blowout grain halo going out to at least 1500 AU. This model...
... likely to host planets with liquid water. The exoplanet system, named after the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile, is located in the Aquarius constellation, which is about 40 light years (235 trillion miles...
... that crashes into each other and sticks together until a ball of rock the size of a small planet (a planetesimal) is left. These huge boulders then combine under the force of gravity to form protoplanets – a large planetary embryo...
... interstellar asteroids hiding in plain sight for billions of years. The objects in question are known as Centaurs - peculiar planetesimals as large as 200 kilometres (125 miles) in diameter, that cross the orbits of one or more of the giant planets...
... the newly-formed planets was full of debris and collisions were commonplace. Large asteroids – we call these planetesimals – were constantly hitting the Moon and the other planets.” How the Moon formed is a matter of debate...
... million years from the initial collapse of a giant molecular cloud a light-year across to the creation of millions of planetesimals that would eventually form the planets. These time constraints have been made possible by using atomic...