One year from today — starting at 12:45 a.m. UTC — MESSENGER will transition from orbiting the Sun to being the first spacecraft ever to orbit the planet Mercury. ”We are finally closing in on the most intense phase of the mission,” says MESSENGER Principal Investigator Sean Solomon, of the Carnegie Institution of Washington. “MESSENGER’s six and a half years of interplanetary flight are a long warm-up for the main event, when we are in orbit about Mercury. The final year of that flight will be a busy time for the team, as we review orbital operation plans for all spacecraft subsystems.”