This was one of the first vessels the Sisters of EVE made available to capsuleers. It had been under development by the Sanctuary corporation, whose interest in exploration includes not only search & rescue operations but also a constant inquiry into the nature of the EVE Gate. Thanks to the Sisters' efforts and the Sanctuary's particular expertise, the Astero is an agile, tenacious ship that aptly adheres to the mantra of both rescuers and explorers: Stay safe, stay hidden, and use every tool at your disposal.
It is particularly adept at venturing into dangerous territories, not merely in recovering whatever may be of interest but also in being able to safely bring it back. Its engines have alternate power sources that come into play should any of its cargo - for which it has plenty of room - cause serious interference with internal systems. Its carapace is extremely well armored for a ship this agile, and covered in sensors capable of letting its crew track a myriad of different organic signatures. The crew itself is safely protected from any number of transmittable ailments from rescues and other unexpected passengers, thanks to special quarantine bays that are conveniently located near jettisonable openings.
And lastly, an ingenious but cryptic transfer in part of the warp core functionality to an outlying cylindrical structure means the Astero is able to run certain higher-level cloaking functions with very little technical cost, and minimal interference from warp. The Sisters of EVE have refused to comment on this technology, other than to recommend it not be tampered with.