A NASA spacecraft that will fly closer to the sun than any mission before will launch on a Delta 4-Heavy rocket in 2018, requiring a boost from the largest active launcher in the U.S. inventory and repeated flybys around Venus to reach an operating post inside the solar atmosphere.

United Launch Alliance is expected to reveal its design for a next generation satellite launcher Monday, outlining a 20-year roadmap to develop a new methane-powered first stage booster, an advanced space tug and a reusable rocket engine.

These photos show a 194-foot-tall United Launch Alliance Atlas 5 rocket standing on pad 41 at Cape Canaveral Space Force Station in advance of a planned launch with the U.S. Space Force’s fifth SBIRS missile warning satellite.