SternisheFan tips news that William Shatner and Wil Wheaton have each narrated a NASA video titled "Grand Entrance," which documents the upcoming descent and landing of Mars rover Curiosity onto the Red planet. Curiosity is the nickname for the Mars Science Laboratory, the largest rover ever sent to another world. It is scheduled to land on Mars on August 5 at 10:31PM PDT (August 6 at 05:31 UTC), and the event will be broadcast live on NASA TV. The landing process documented in the video will take about 7 minutes, and it has to go perfectly all on its own — the time delay caused by the 154-million-mile distance to Earth means that signals will take 14 minutes to even reach us. For further details, check out Wil's video or William's. NASA's fact sheet (PDF) has more information as well.