In recent years there have been a number of modest ‘tugs’ brought online to ferry small satellites to designated orbits. These miniature spacecraft provide so-called last-mile service and are particularly useful for satellites that launch as a part of rideshare missions and seek to reach a different altitude or inclination than that of the primary payload.
However these space logistics vehicles, offered by a variety of companies, such as D-Orbit, Momentus, Launcher, and several others, generally are designed for satellites with a mass of a few dozen to a few hundred kilograms.
What has been lacking so far is a larger in-space tug that can haul bigger satellites to more distant orbits. That’s the market that a new spacecraft built by Impulse Space, Helios, intends to serve.
Read More – Science – Ars Technica