"Thursday's a huge day for us" -- NASA official Mark Geyer said in a prelaunch briefing, wrote The Christian Science Monitor. Apparently, Dec. 4 marks another possible milestone for the human race, as NASA launches the spacecraft slated to bring people to the moon and beyond.

Thursday's event will see the first unmanned test flight of the Orion capsule, situated on top of a Delta IV Heavy rocket. According to the Christian Science Monitor , the rocket takes off from Kennedy Space Center in Florida by 7:05 a.m. ET (12:05 p.m. GMT).

The Delta rocket is America's largest booster, as reported by Reuters. The outlet recorded Orion's expected 4 1/2-hour mission -- and we've listed some highlights below.

Be guided: minute:second from takeoff

1:25 - Orion speeds up

5:30 - The last of three liquid-fueled boosters burns out and separates from upper-stage engine

17:00 - Second-stage engine shuts down; Orion is left in its initial orbit

180:00 - Orion goes through intense radiation in the Van Allen Belts; Craft reaches peak altitude of 3,600 miles (5,800 km)

180:23 - Orion separates from service module and Delta upper stage

180:57 - Orion steers to position for atmospheric re-entry

240:15 - Orion heats temperature peak of 4,000 degrees Fahrenheit (2,200 degrees Celsius) during re-entry

240:23 - Orion settles in the Pacific Ocean; Recovery teams retrieve spacecraft

Business Week took note of Orion's resemblance with that of the Apollo, the space vessel that brought men to the moon over four decades ago. The source cited the current spacecraft's physical features, paying attention to the blunt bottom tip -- a capsule-ish design which addresses the craft's safety as it returns to the planet from distant missions.

NASA guidance and navigation engineer Kelly Smith explained in an earlier Reddit discussion, "The 'capsule shape' happens to be good aerodynamically for slowing down the vehicle without it burning up like a meteor."

Smith also revealed why sharp shapes aren't much of a good choice, "Sharp shapes tend to heat up too much and melt / vaporize. A blunt shape works well hypersonically for keeping the heating to more manageable levels. If you look at ballistic missiles, all of their nose cones are 'blunt' as well (spheres, sphere-cones, etc.) to deal with the extreme heating environment."

Meanwhile, ABC News cited NASA's high-end multimedia countdown clock that awaits Orion's launch. The system was reported to cost $280,000, presenting functionality similar to sports stadium displays.

Watch Ustream's live webcast of Orion's launch mission below. The event may be watched directly from NASA here.

Broadcast live streaming video on Ustream