The largest balloon born telescope ever has taken off from Swedish Space Corporation's (SSC) launch facility at Esrange Space Center in northern Sweden. The balloon, the technical equipment and the gondola weigh around 6 ton all together and this is by far the heaviest payload ever launched with a balloon from Esrange.

The telescope is now floating at high altitude and has expanded to 950.000 m3, which is around 140 meters in diameter. It has just left the Norwegian coast heading for Canada where it will land in about 4-6 days. The exact landing spot depends on the wind direction and for how long the flight will last.

Why fly from Esrange Space Center?
The Esrange facility is superbly located for a launch of such a telescope. During the summer, the stratospheric winds carry the balloon westwards at nearly constant latitude, and under continuous sunshine. Thus while most conventional balloon flights must be terminated at sunset, a long-duration flight from Esrange can stay at float for about a week until it reaches Western Canada.

By using ELINK, an SSC Ethernet based telemetry system, the instruments onboard SUNRISE will be calibrated during the initial phase of the flight. An extra mobile ground station for ELINK has been mounted at the Norwegian coast to extend the time for calibration with high bandwidth data. The data from the mobile station is routed over Internet to Esrange. The communication with SUNRISE will after loss of line of sight data, go through different satellite systems during the rest of the flight.

"We started the preparations together with the SUNRISE team almost four years ago and it is very inspiring to see the first European payload of this size take off, says Mr. Lennart Poromaa, head of Science Services Division at Esrange Space Center.

"We have developed the ELINK system for payloads and missions like SUNRISE and we look forward to many more launches of this dignity, with scientific teams from all over the world".

"During the flight the telescope will observe the sun without interruption thanks to the midnight sun period", says Dr. Peter Barthol, project manager for the mission, and adds: "Our onboard instruments will measure details on the solar surface with an unprecedented spatial and temporal resolution. The conditions at 37 km float altitude are close to those in space, so we are not limited in performance by the atmospheric seeing as ground based telescopes usually are. And we have access to the ultraviolet regime of the solar light, which will give us new insights into the physics of the Sun. We are so happy about this successful launch and are eager to get the first scientific data after the instrument check-out phase."

The SUNRISE mission
SUNRISE is an international scientific mission with the objective to study the structure and dynamics of the solar magnetic field.

The scientific teams involved come from the Max Planck Institute for Solar System Research (PI institution) and the Kiepenheuer Institut for Sonnenphysik in Germany, the Instituto de Astrof�sica de Andaluc�a and the Instituto de Astrof�sica de Canarias in Spain and the High Altitude Observatory /NCAR in the U.S.. The scientists have been working together for seven years to make this flight happen.

SUNRISE is also part of the framework of NASA's LDB (Long Duration Balloon) program. The Colombia Scientific Balloon Facility (CSBF) has the overall operational responsibility for the campaign activities and they were supported by a project manager and an operational team from the Swedish Space Corporation stationed at Esrange.