HESSI Credit: Manufacturer Image |
AKA: SA-200S. Status: Operational 2002. First Launch: 2002-02-05. Last Launch: 2002-02-05. Number: 1 . Gross mass: 304 kg (670 lb).
The satellite rotated at 15 rpm, imaging hard X-ray flares from the Sun by reconstructing the Fourier components from the time modulation of the flux through a set of 9 grids each 9 cm in diameter. It was expected to make images with a resolution of 2 arcseconds at 40 keV energies and 36 arcseconds at 1 MeV energies. Launch delays meant HESSI missed some of the best flares at solar max.
NASA NSSDC Master Catalog Description
RHESSI (Ramaty High Energy Solar Spectroscopic Imager) is an American (NASA) solar flare observatory that was launched at 20:58 UT on 5 February 2002 by a Pegasus XL rocket which was released from a L-1011 aircraft flying out of the Cape Canaveral AFS. The 293 kg (with fuel), 414 W, 2.2 m (height) x 1.1 m (width) satellite is equipped to image at high resolution solar flares in X-rays and gamma rays. Onboard memory is 4 Gbytes, and telemetry rate is 3.5 Mbits/s. A PDMP exists for archiving the data at the NSSDC.
HESSI, the sixth Small Explorer, carried a rotating modulation collimator transform telescope, imaging solar flares in the hard X-ray spectrum. The launch marked the return to flight of Pegasus after the Hyper-X failure. The launch was originally to have occurred on 28 March 2001. The L-1011 launch aircraft took off at 19:29 GMT from the Cape Canaveral Skid Strip RW30/12, and headed out to the drop area at 28.0 N 78.5 W over the Atlantic. Drop of the Pegasus in the Atlantic Drop Zone at 28.0 N 78.5 W was at 20:58 GMT, with ignition 5 seconds later. The Pegasus reached orbit at 21:07 GMT. On the first pass it was confirmed that the solar panels had opened.
The satellite rotated at 15 rpm, imaging by reconstructing the Fourier components from the time modulation of the solar x-ray flux through a set of 9 grids each 9 cm in diameter. It was expected to make images with a resolution of 2 arcseconds at 40 keV energies and 36 arcseconds at 1 MeV energies. The launch delays meant that HESSI missed some of the best flares at solar max. Air dropped in Mayport DZ.