Much Rumored, Now Confirmed, Local Residents May Hear Their First Sonic Boom Since Shuttle Days

ANN RealTime Update, 122015, 1611 ET: SpaceX has scrubbed the Sunday launch and attempted First Stage landing of the upgraded Falcon 9/Orbcomm launch until 2034 local time, Monday. No problems have been blamed for the delay as SpaceX Boss Elon Musk just tweeted, "Just reviewed mission params w SpaceX team. Monte Carlo runs show tmrw night has a 10% higher chance of a good landing. Punting 24 hrs." ANN will update as we receive more info...

Original Report: SpaceX has confirmed that the company is targeting launch of the 11 ORBCOMM satellites aboard a Falcon 9 rocket from Cape Canaveral Air Force Station, FL. on Sunday, Dec. 20.

The 60-second launch window opens at 8:29 p.m. ET. If needed, a backup launch opportunity is available on Dec. 21.

In addition to the primary mission of launching ORBCOMM’s fleet of commercial communications satellites, SpaceX is attempting a secondary test objective of landing the first stage of the Falcon 9 rocket on land for the first time at SpaceX’s Landing Zone 1. Previous attempts to recover the first-stage of the Falcon 9 have been attempted out at sea using the company’s Autonomous Spaceport Drone Ships. Landing Zone 1 was previously known as Space Launch Complex 13, a former U.S. Air Force rocket and missile testing range last used in 1978. If successful, this test would mark the first time in history an orbital rocket has successfully achieved a land landing.

Just as when the Space Shuttle returned from space, SpaceX notes that there is a possibility that residents of northern and central Brevard County, FL. may hear a sonic boom during landing. SpaceX explains that a sonic boom is the thunder-like noise a person on the ground hears when an aircraft or other type of aerospace vehicle flies overhead faster than the speed of sound, though to be more precise,  as an aircraft flies, it creates a series of pressure waves both in front of it and behind. The waves travel at the speed of sound, and as the speed of the vehicle increases, the waves are merged/compressed, as they intersect naturally as a function of the increased rates. The ultimate result is an often audible shock wave, which travels at the critical speed of Mach 1, some 761 mph (at sea level and 68 °F).

Residents of the communities of Cape Canaveral, Cocoa, Cocoa Beach, Courtenay, Merritt Island, Mims, Port Canaveral, Port St. John, Rockledge, Scottsmoor, Sharpes, and Titusville in Brevard County, Fla. are mostly likely to hear a sonic boom, although what residents experience will depend on weather conditions and other factors.

FMI: SpaceX.com/webcast begins at approximately 8:05 p.m. ET.