Sunrise (telescope)
Encyclopedia
Sunrise is a solar telescope
in the ultraviolet
, that hangs from a high altitude balloon
. The strong absorption of UV radiation by the Earth's atmosphere makes it challenging to carry out ground-based observations at these wavelengths. A balloon mission reaching altitudes of above 30 km benefits from a reduction of UV absorption by 99%, making engineering solutions for the telescope easier. The launch sites are either in antarctica or in the arctic
region to make uninterrupted observation of the sun
over several days possible. The telescope has a 1 metre
primary mirror
that directs the 1 kW of solar radiation to the first focal point where 99% of the radiation is reflected out of the telescope, the remaining light is transferred into several instruments.
The one metre diameter primary mirror is made from a glass ceramic zerodur
, it is the central part of the gondola of nearly 2 tons. Solar panels of 1.5 kW out put power are used to power the onboard equipment and a hard disk
array of 2 x 2.4 Terabyte is used to store the data during flight.
Solar telescope
A solar telescope is a special purpose telescope used to observe the Sun. Solar telescopes usually detect light with wavelengths in, or not far outside, the visible spectrum.-Professional solar telescopes:...
in the ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
, that hangs from a high altitude balloon
High altitude balloon
High-altitude balloons are unmanned balloons, usually filled with helium or hydrogen that are released into the stratosphere, generally reaching between ....
. The strong absorption of UV radiation by the Earth's atmosphere makes it challenging to carry out ground-based observations at these wavelengths. A balloon mission reaching altitudes of above 30 km benefits from a reduction of UV absorption by 99%, making engineering solutions for the telescope easier. The launch sites are either in antarctica or in the arctic
Arctic
The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...
region to make uninterrupted observation of the sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
over several days possible. The telescope has a 1 metre
Metre
The metre , symbol m, is the base unit of length in the International System of Units . Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole , its definition has been periodically refined to reflect growing knowledge of metrology...
primary mirror
Primary mirror
A primary mirror is the principal light-gathering surface of a reflecting telescope.-Description:The primary mirror of a reflecting telescope is a spherical or parabolic shaped disks of polished reflective metal , or in later telescopes, glass or other material coated with a reflective layer...
that directs the 1 kW of solar radiation to the first focal point where 99% of the radiation is reflected out of the telescope, the remaining light is transferred into several instruments.
The one metre diameter primary mirror is made from a glass ceramic zerodur
Zerodur
Zerodur®, a registered trademark of Schott Glass Technologies, is a lithium aluminosilicate glass-ceramic produced by Schott AG since 1968. It has been used for a number of very large telescope mirrors including Keck I and Keck II. With its very low coefficient of expansion it can be used to...
, it is the central part of the gondola of nearly 2 tons. Solar panels of 1.5 kW out put power are used to power the onboard equipment and a hard disk
Hard disk
A hard disk drive is a non-volatile, random access digital magnetic data storage device. It features rotating rigid platters on a motor-driven spindle within a protective enclosure. Data is magnetically read from and written to the platter by read/write heads that float on a film of air above the...
array of 2 x 2.4 Terabyte is used to store the data during flight.
Instruments
- CWS, Correlating Wavefront Sensor is a CCD camera with 1 kHz read-outs responsible generate the images necesarry for image stabilizationImage stabilizationImage stabilization is a family of techniques used to reduce blurring associated with the motion of a camera during exposure. Specifically, it compensates for pan and tilt of a camera or other imaging device. It is used in image-stabilized binoculars, still and video cameras, and astronomical...
and proper alignment. - SUFI, Sunrise Filter Imager observes the sun in five distinct wavelength, 220, 279.2, 300, 323 and 388 nm, on a 2048 x 2048 pixel CCD, through a filter wheeleFilter (optics)Optical filters are devices which selectively transmit light of different wavelengths, usually implemented as plane glass or plastic devices in the optical path which are either dyed in the mass or have interference coatings....
. - IMaX, Imaging Magnetograph eXperiment observes the Zeeman splitting of the iron line (FeI) around 525 nm. The observed field of view is 50 x 50 arcseconds.
- SUPOS, Sunrise Polarimetric Spectrograph observes the Zeeman splitting of the calciumCalciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
line (CaII) around 845 nm. The observation will take place in the two polarized planes and will be read out by a CCD camera.
Flights
- Sunrise's first flight was launched at 8:27 June 8, 2009 from EsrangeEsrangeEsrange Space Center is a rocket range and research centre located outside the town of Kiruna in northern Sweden. It is a base for scientific research with high altitude balloons, investigation of the aurora borealis, sounding rocket launches, and satellite tracking, among other things...
, near KirunaKirunaKiruna is the northernmost city in Sweden, situated in Lapland province, with 18,154 inhabitants in 2005. It is the seat of Kiruna Municipality Kiruna (Northern Sami: Giron, Finnish: Kiiruna) is the northernmost city in Sweden, situated in Lapland province, with 18,154 inhabitants in 2005. It is...
, SwedenSwedenSweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
and it landed 1.45 June 14, 2009 on Somerset Island, NunavutNunavutNunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...
, northern CanadaCanadaCanada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
after a flight duration nearly six days.
External links
- Homepage
- Offizielles Missions-Blog (German)
- Reports, films and images (englisch)
- Presentation (German)
- First engineering balloon flight in 2007 a detailed account (English)