Data Recovery Capsules Prove Effective in Backing Up Balloon-Based Telescope Data

An international team of scientists has successfully demonstrated the use of data recovery capsules (DRSs) to safeguard vital astronomical data collected by balloon-borne telescopes. This breakthrough technology offers a promising solution to the challenges of data loss in high-altitude balloon missions, where communication disruptions or unexpected descent scenarios can jeopardize the integrity of collected information.

(a) Close-up of a DRS in flight configuration. The closed-cell foam shell surrounding the DRS can be seen poking out below a skirt of aluminized Mylar. It is further protected on two sides by sheets of foam insulation also covered by aluminized Mylar. Cables are routed upwards on the mounting frame. (b) superBIT suspended on the launch crane. Four DRS capsules can be seen at the bottom, each attached to a corner of the frame holding the solar panels. The blue and white object hanging between them is a ballast hopper. Throughout its mission, the telescope keeps its back (on the right in these photos) oriented towards the sun. Credit: Aerospace (2023). DOI: 10.3390/aerospace10110960

The study, published in a special issue of the journal Aerospace, details the team's test of four DRS capsules, each carrying 5 TB of telescopic data, launched aboard a helium-filled, super-pressurized balloon. The mission, involving the superBIT telescope, aimed to capture astronomical images from the Earth's stratosphere, approximately 99.5% above the atmosphere.

To ensure data resilience in the event of communication or flight control failures, the research team incorporated DRS capsules as a backup mechanism. These capsules were designed to parachute back to Earth, independently retrieving the stored data.

The mission commenced on April 16, with the balloon and its cargo ascending to an altitude of 40 kilometers. Over the following 40 days, the telescope diligently captured images of galaxy clusters, seeking evidence of gravitational lensing to support the existence of dark matter. Data transmission relied on Starlink and NASA's TDRSS systems.

However, on May 1, the Starlink connection abruptly terminated, and three weeks later, the TDRSS link also began to falter. Faced with these communication disruptions, the team initiated the telescope's descent using its attached parachute.

Before the descent, two of the four DRS capsules were released, equipped with Global Navigation Satellite System (GNSS) receivers and communication systems to track their whereabouts. Upon release, it became apparent that only three of the four capsules were functioning. The malfunctioning capsule was not released, and another was retained onboard to assess its performance upon landing with the balloon.

Due to the freezing temperatures during the descent, communication with the capsules was lost for most of the journey. However, as the batteries warmed upon landing, communication resumed, enabling the researchers to locate and retrieve both functioning capsules and the data they carried.

The successful recovery of the DRS capsules and their stored data validates the effectiveness of this technology in safeguarding scientific data collected by balloon-borne telescopes. This innovation promises to significantly enhance the reliability of high-altitude balloon missions, ensuring the preservation of valuable astronomical observations.