Description of the payload

The instrument, is the first one aimed to obtain focused images of astronomical X-ray sources at hard X-ray energies (20-75 keV).

The key component (the hard X-ray optics) are full-shell electroformed-nickel-replicated (ENR) mirrors coated with iridium to enhance high-energy reflectivity. As the critical grazing angle for reflection varies approximately inversely with energy, these mirrors employ smaller angles than their low-energy counterparts and consequently have smaller diameters and collecting areas per shell. The mirrors have a 6 meter focal length.

To exploit the full potential of the HERO optics necessitates a balloon gondola that can provide commensurate pointing accuracy, stability, and pointing knowledge. The HERO gondola utilizes a coarse aspect system for slewing based on a differential global positioning system (GPS) and a fine inertial-mode pointing system that uses a novel day/night aspect camera system to update onboard gyroscopes. The total payload dimensions are 25 feet long, 6.5 ft wide and 16 ft high.

Details of the balloon flight and scientific outcome

Launch site: Scientific Flight Balloon Facility, New Mexico, US  
Balloon launched by: Columbia Scientific Balloon Facility (CSBF)
Balloon manufacturer/size/composition: Zero Pressure Balloon Raven - 39.570.000 cu ft - 0.8 Mil.
Flight identification number: 569N
Payload weight: 3220 lbs
Overall weight: 5500 lbs

The instrument performed very well. The scientific team managed to made during the flight 4 observations of galactic x-ray sources and one observation of an extragalactic source.

External references and bibliographical sources

Images of the mission

The image shows the HERO payload in the hangar doing pointing tests at the night sky with the optical bench deployed The HERO telescope just before being released by the launch vehicle The initial ascent phase of the balloon View of the balloon in flight took from an airliner in flight over New Mexico Another view of the balloon in flight took from an airliner in flight over New Mexico