A private European aerospace company is set to make the first test flight of its orbital launch vehicle. Isar Aerospace says the launch window for its Spectrum rocket from an island in northern Norway is about three hours Monday afternoon. The launch time is subject to weather, safety and range infrastructure, and the flight could also take place later in the week. The Spectrum is a two-stage launch vehicle designed for small and medium-sized satellites. The startup says it has raised more than $435 million in capital and hopes to build up to 40 launch vehicles per year in the future to put satellites into orbit.