Onsala Twin Telescopes

The Onsala Twin Telescopes (OTT) are part of the global geodetic Very Long Baseline Interferometry (VLBI) network. Radio telescopes on the entire globe are observing extra galactic radio sources simultaneously to determine Earth Orientation Parameters (EOPs), source positions and station coordinates as well as velocities. Geodetic VLBI is used to maintain the International Terrestrial Reference Frame as well as the International Celestial Reference Frame. Popular results derived from geodetic VLBI are plate tectonics, nutation and precession of the Earth and the solar time UT1.
The OTT was inaugurated in 2017 and is fully compatible to the VLBI Global Observing System (VGOS) . That means the telescopes can reach any point on the sky within 30 seconds and are equipped with broadband receivers.
This image was created by stacking 160 individual images. The combined exposure time is 80 minutes.