What to expect: SpaceX's Falcon Heavy launch from KSC

Emre Kelly
Florida Today
SpaceX's three-core, 27-engine Falcon Heavy launch vehicle sits on pad 39A at Kennedy Space Center in December 2017.

Update: Launch of Falcon Heavy at 3:45 p.m. ET! SpaceX also landed both boosters at Cape Canaveral Air Force Station eight minutes after liftoff.

SpaceX's three-core Falcon Heavy rocket will light up the afternoon sky over Kennedy Space Center Tuesday, capping off months of rapidly growing excitement for the launch vehicle's demonstration flight.

The 230-foot-tall, 27-engine rocket is slated to lift off on its first mission at 1:30 p.m., the opening of a two-and-a-half hour window at pad 39A.

"The weather looks good, rocket's looking good," SpaceX CEO Elon Musk said during a pre-launch conference on Monday. "I'm looking forward to it."

Here's what to expect:

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Thousands traveling to the Space Coast

About 100,000 people could visit the Space Coast for the launch, according to an estimate by Space Coast Office of Tourism Executive Director Eric Garvey – and that number could be as high as half a million when factoring area residents who will watch.

"It will be a historic event, so we expect the community to fill up in terms of hotel rooms and any kind of lodging," he said.

From causeways to beaches, the best viewing spots will likely be packed with spectators, so area officials are recommending that people get to their spots early, relax and enjoy the show.

Weather looks good for liftoff window

Photographers set up remote cameras around SpaceX's Falcon Heavy rocket at pad 39A on Monday, Feb. 5, 2018.

Weather conditions are 80 percent "go" for the attempt, according to the Air Force's 45th Weather Squadron, and forecasters cited the presence of strong liftoff winds and thick clouds as the only concerns. Expect temperatures in the 70s and partly cloudy skies during the launch window.

In the event of a delay, the forecast for Wednesday looks similar, though conditions would dip to 70 percent "go."

Most powerful rocket in the world

SpaceX's Falcon Heavy rocket is seen here at a Kennedy Space Center hangar. The three-core, 27-engine rocket is slated to launch from KSC in early 2018.

At liftoff, Falcon Heavy's 27 Merlin main engines will generate more than 5 million pounds of thrust, making it the most powerful operational rocket in the world. That thrust means the 40-foot-wide rocket can transport about 141,000 pounds to low Earth orbit – nearly three times the amount of a typical Falcon 9.

"I'm really hopeful for this flight going as planned," Musk said Monday. "I'm sure we've done everything we could do to maximize the chances of success for this mission."

Expect the rocket to head east over the Atlantic Ocean.

Booster landings and sonic booms

The three boosters making up the first stage of SpaceX's first Falcon Heavy rocket, seen inside the company's hangar at Kennedy Space Center's pad 39A.

Shortly after liftoff, Falcon Heavy's two previously flown side cores will detach, fire cold gas thrusters to perform a flip maneuver, then descend toward Cape Canaveral Air Force Station's Landing Zone 1 and 2. The simultaneous return of two boosters about eight minutes after launch means the Space Coast will feel twice the sonic boom energy of a typical Falcon 9 mission, but no need to be alarmed – they can be startling, but not harmful or damaging, according to NASA.

The core stage, meanwhile, will burn slightly longer before separating from the upper stage. It will then perform a similar flip maneuver and target a landing on SpaceX's Of Course I Still Love You drone ship stationed a few hundred miles off the east coast of Florida. Expect it to return to Port Canaveral before the end of the week.

Tesla payload – and passenger – targeting orbit

The Tesla Roadster and "Starman" prior to encapsulation at pad 39A

Musk's personal 2008 Tesla Roadster, an all-electric sports car that helped sustain his energy company in its formative years, is encapsulated in the rocket's protective fairing for Tuesday's flight, but with a new addition: A "Starman" mannequin in the driver's seat, donning the spacesuit that astronauts will wear on SpaceX flights to the International Space Station.

After a coast phase, the Roadster will separate from the upper stage and target a heliocentric orbit, meaning it will ultimately orbit the sun and enter into close proximity to Mars at certain points along its path.

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"It will be in an elliptical orbit with one part of the ellipse being at Earth orbit and one part being at Mars orbit, so it will essentially be an Earth–Mars cycler," Musk said. "We estimate it'll be in that orbit for several hundred million years, maybe even in excess of a billion years."

Three cameras attached to the vehicle will provide visuals for transmission back to Earth.

What's next?

If successful, Musk said the next Falcon Heavy mission could be in three to six months, though with a customer payload. SpaceX has been contracted by Arabsat, ViaSat and the Air Force to take payloads to orbit on Falcon Heavy.

Musk, however, still emphasized the mission's challenges on Monday, noting that plenty of things can't be tested on the ground: interactions between the boosters while in flight; the effect of supersonic shockwaves; the possibility of ice falling off the upper stage and impacting one of the boosters; and the correct operation of the separation system, to name a few.

"Guaranteed to be exciting, one way or another," he said. "I say tune in – it's going to be worth your time."

Contact Emre Kelly at aekelly@floridatoday.com or 321-242-3715. Follow him on Twitter and Facebook at @EmreKelly.

Launch Tuesday:

  • Rocket: SpaceX Falcon Heavy
  • Mission: Demonstration flight with Tesla Roadster
  • Launch Time: 1:30 p.m.
  • Launch Window: Until 4 p.m.
  • Launch Pad: 39A at Kennedy Space Center
  • Weather: 80 percent "go"

Join floridatoday.com at noon for countdown chat and updates, including streaming of SpaceX's launch broadcast starting 15 minutes before liftoff.