Astronomers have not only double vision, but triple, quadruple, quintuple and sextuple vision. Distant galaxies can appear banana-shaped. Giant “gravitational lenses” are found billions of light years away from us. These act as natural magnifying glasses, allowing us to study details in even more distant objects which would otherwise be invisible. Can these magnifying glasses reveal the first stars and galaxies which were formed in the universe?
What do they tell us about how the universe has evolved from the beginning until today? Some recent discoveries of such gravitational lenses have given us surprising answers, challenging our theories about the universe.
Håkon Dahle, researcher at the Institute for Theoretical Astrophysics, University of Oslo, on gravitational lenses, dark matter, galaxy clusters and galaxy formation. He has worked at the Nordic Optical Telescope and the large telescopes in Hawaii and Chile, head of the organization for the Astronomy Year in Norway in 2009, and is currently a board member of the Norwegian Astronomical Society and is one of the organizers of this conference. Dahle has also been an active amateur astronomer since age 11, with a special interest in comets, meteors and variable stars.