Shooting stars hold answers to questions about universe
Meteors – the shooting stars occasionally flashing through the night sky – could help answer questions about the origin
of our solar system.
Professor Jack Baggaley at the University of Canterbury has been awarded a grant from the competitive Marsden Fund to
determine the exact source of the many tiny grains of dust we see as shooting stars as they burn after entering the
Earth’s atmosphere.
Most of these dust grains originate in our own solar system as debris left over from the break-up of comets. However, a
small proportion enter our atmosphere coming directly from interstellar space – the vast regions between the stars.
These particles form dust clouds in space which are known to be the nurseries for young stars, newly formed planetary
systems and perhaps life itself.
The trail left by meteors as they plunge into the atmosphere can be detected with the help of radar techniques by
bouncing a radio signal off the moving particle and recording the echo. New Zealand is home to a unique radar facility,
the Advanced Meteor Orbit Radar or AMOR, which can determine accurate positions for the meteor’s trail. Using this
technique, Professor Baggaley has already been able to demonstrate that some of the fiery dust grains piercing the
Earth’s atmosphere enter at much higher speed and a different angle from the majority of particles.
The conclusion that, while most of the dust grains come from within the solar system, a small percentage indeed
originates in outer space, brought Professor Baggaley’s group acclaim in the international science community. The group
will further improve the AMOR system by building a second antenna pointing in a different direction to the original
setup. This will greatly enhance the group’s ability to detect the meteors of interstellar origin and to determine their
properties. The group is also working with scientists from the European Space Agency, comparing their data with those
obtained from space probes such as Galileo and Ulysses.
Their results will lead to a better understanding of interstellar dust and its role in the formation of planetary
systems such as our solar system.
Professor Baggaley’s grant is worth $145,000 for the first year, and $135,000 for each of the following two years.