Photos: Atlas 5 rocket aims for International Space Station

A powerful European Ariane 5 rocket blasted off from French Guiana late Friday and boosted a pair of satellites into space for a seven-year plunge into the inner solar system, a voyage requiring seven planetary flybys to slow down enough in the sun’s gravitational clutches to slip into orbit around hellish Mercury.

Rocket Lab, a company eyeing a market to launch small satellites, said Monday that bad weather at its privately-operated launch base on New Zealand’s North Island kept a commercial Electron booster from lifting off on its maiden test flight for the second day in a row.

The Italian PRISMA Earth observation satellite is set to ride a Vega launcher into a 382-mile-high (615-kilometer) orbit Thursday night from French Guiana on a mission that will take less than one hour from liftoff until spacecraft separation.