As Beck explains this story, the Beiderman family is at home watching the conference, shocked at what they are hearing-- Leo is very much alive and well, at home watching with his family. The door rings and Leo finds Sarah there with her parents, and the whole neighborhood is beginning to converge on the Beiderman home, seeing that Leo is still quite with them all. Newsweek publishes a story about Leo and the events regarding his supposed death.
Leo speaks to his school and the students' families regarding his notifying Dr. Wolf about the comet, and he realizes that he was most likely presumed to have perished along with Wolf because Wolf shared credit with Leo about the comet's discovery. Leo quickly gains near celebrity status over having first discovered the comet.
The Messiah crew and their families are attending a small garden party which gives us a look into their day to day lives. Baker and Commander Monash are both married; Baker and her husband have a young daughter while Monash's wife is pregnant with their first child. Simon is engaged and looking forward to his wedding, but less than enthused about his fiancée's affinity for attending church. Capt. Tanner is widowed with twin sons grown to young adulthood and attending Naval Academy where Tanner himself graduated from.
Tanner is also friends with Otis 'Mitch' Hefter (Kurtwood Smith), a senior NASA official who will serve as mission control director at a facility in Houston. Tanner and Hefter talk about the rest of the Messiah crew, about whom Tanner has concerns regarding their training being done in simulators, and they have little actual space flight experience.
Partenza talks with a young boy and explains the hazards of the mission: the comet's rotational period means the Messiah crew only has a seven hour window before the sun will 'rise' on the section they will be working on, and during the time that the sun is shining on that segment, there will be dangerous and volatile outgassings from the comet's interior. The Messiah crew needs to work quickly to avoid this hazard.
Later that evening, the crew members are relaxing and drinking at a bar, though Tanner sits separately from the others. He overhears them talking about him. The other crew members respect Tanner's reputation, but they downplay Tanner's having been the last astronaut to walk on the moon, and believe that he is only on the mission more as a public relations move by Washington, because he is a familiar face.
Tanner finally goes over to their table and says he knows that the other crew members don't want him with them, but he insists they will need his experience-- all of their simulator training will be like a video game compared to the actual mission. He is the only one with actual experience landing a spacecraft on an actual landing surface.
Two months later, the Messiah crew is ferried by the space shuttle Atlantis to dock with the orbital station on which the Messiah was constructed. A news crew explains the Messiah's construction, and that it is powered by a prototype nuclear propulsion system code-named Orion, that was originally developed by Russian engineers for nuclear warfare. This propulsion system will allow the Messiah's crew to reach the comet well in advance of its arriving close to Earth.
Five months after the Messiah's departure, Caley's MSNBC news crew is meeting for another conference, discussing their ongoing coverage of the Messiah's mission. Everyone is asked about their role and latest contributions. Caley announces (to Beth's shock) that Jenny has been given a news anchor position for the coverage program. Being known as the one who broke the story on the comet, Jenny has likewise gained a great deal of national status.
The Messiah crew begins its approach to the comet, and they are in awe of its true size.
They are making preparations to detach the main spacecraft from its propulsion system and fly down to the comet's surface to plant their nuclear warheads.
Monash, Simon, Partenza, and Tulchinsky suit up for the planting of the warheads while Baker and Tanner are at the helm for the landing.
Tanner gives an analogy of Mississippi River boat pilots, to explain that this part of the mission is in his hands and he will deliver the Messiah safely to the comet's surface. Baker smiles respectfully as she listens to Tanner's analogy.
Jenny begins her news program's coverage of the event. She tells everyone watching that interference from rock, gravel and gas from the comet will eventually cause them to lose video transmission with the Messiah. As she speaks, the picture is lost and Jenny assures everyone that the station coverage will continue and they will stay on air during the next hour in which the mission is being undertaken.
The Beiderman and Hotchner families are shown watching the program together; Sarah's mother, Vicky Hotchner (Denise Crosby) is pregnant with her second child, and Leo and Sarah are growing closer.
As Baker and Tanner maneuver the Messiah for landing, they must fly through a veritable minefield of rocks caught in the comet's tail. Some of them are very large. Despite their best efforts, a few rocks hit the ship and some minor damage is sustained.
They nonetheless manage to bring the Messiah safely down, fire tether pitons and land intact on the comet's surface.
As they open the cargo bay doors so the surface crew can begin drilling into the comet to plant the warheads, Baker and Tanner start a computerized countdown. They have just under six and a half hours before 'sunrise' on their part of the comet. Jenny begins an explanation of the next procedure of the Messiah mission: mechanical moles will be used to drill 100 meters into the comet, each one carrying a 5000 kiloton nuclear warhead.
The Messiah is carrying eight of them in total. Almost immediately the mission begins going awry. The moles prove to be unable to drill as deeply into the comet's surface, as quickly as is required. They are at just over an hour and a half before sunrise. Baker and Tanner, waiting anxiously in the spacecraft, know it is taking too long.