NASA has awarded $4.3 million for the final phase of construction and flight of an experiment led by the University of Chicago to send a scientific balloon to 110,000 feet above the Earth.
The project, termed Extreme Universe Space Observatory on a Super Pressure Balloon or EUSO-SPB2, is searching for messengers from outer space: tiny, highly energetic particles that hit the Earth on their way from elsewhere in the universe.
“This is an important step towards solving the mystery of where in the universe these particles are coming from, and how they could possibly be made,” said Angela Olinto, the University of Chicago Albert A. Michelson Distinguished Service Professor of Astronomy and Astrophysics, who heads the experiment. “These are particles that we simply cannot create ourselves on Earth; we need to use these space travelers to learn more about them.”
The mission, which involves 280 researchers from 13 countries and 77 institutions, consists of two instruments which will be attached to a high-altitude balloon launched by NASA. The balloon and its cargo are currently under final construction and assembly.
When completed, EUSO-SPB2 will ride wind currents about 20 miles above the Earth around the southern hemisphere, gathering data and searching for tracks left by two types of incoming particles.
Two telescopes, two particles
EUSO-SPB2 carries two different telescopes because it wants to detect two different kinds of particles that come from outer space.
One type is called an ultra-high-energy cosmic ray. These are charged particles that have been accelerated to extremely high energies elsewhere in the universe, and they occasionally slam into the Earth’s atmosphere. They are extremely powerful; they are the highest-energy particles we know of in the universe.
The other type of particle is a neutrino. These particles, on the other hand, rarely interact with matter at all. This aloofness makes them interesting to scientists, because they can carry information from far away in the galaxy without being distorted like other particles do. However, it also makes them very hard to detect in the first place.
We think both these particles come from outside the Milky Way and even from faraway galaxies. But no one has been able to trace them back to their source in the sky. Scientists would love to track them to their origins, because this could tell us how the particles were made: by supermassive black holes, or two massive neutron stars slamming into one another, or even a gigantic shock between clusters of galaxies. The particles would carry information about that event to us, millions or billions of light-years away.