Nearly seven years ago, on a steamy morning in Florida, a small team of SpaceX engineers was fueling a Falcon 9 rocket for a pre-launch firing test of its nine Merlin engines.

It had been a difficult but successful year for the California rocket company, which finally was starting to deliver on a long-promised increase in cadence of launches. A team of dozens of engineers and technicians at SpaceX's facilities in Cape Canaveral had suffered through grueling months of perfecting the "load-and-go" fueling process involved with the Falcon 9 rocket.

To maximize its payload capacity, the booster used super-chilled liquid oxygen to cram as much on board the rocket as possible. But once it was fueled, the rocket had to go quickly or the liquid oxygen would rapidly warm in the Florida heat. That summer the team of engineers had been pushing hard to compress the propellant loading time to launch with the coldest oxygen possible and max out the vehicle's performance.

That morning, to save a single day in the pre-launch preparation process, SpaceX had already affixed an Israeli satellite on top of the Falcon 9 rocket ahead of the static fire test. And the countdown was going smoothly on the morning of September 1, 2016, until it wasn't. Completely out of the blue, the rocket exploded violently, showering pieces of the vehicle into the swamplands for miles around. The $200 million satellite swan-dived to the ground, a total, fiery loss. The engineers had found the limit for how fast they could fuel the rocket.

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The Amos-6 accident—known internally at SpaceX as "Flight 29"—was a wrenching failure for a launch company. With the destruction of the Space Launch Complex-40 pad, SpaceX had no other pads in service at the time, and it had no rockets to launch. It was a low moment and emboldened doubters at NASA and in the human spaceflight community as SpaceX worked toward human launches on board its Falcon 9 rocket. They would say things like, You want to put humans on that?

But it was also the last serious accident involving the Falcon 9 rocket.

Since the loss of that rocket, SpaceX has strung together a remarkable 199 successful launches of the Falcon 9 rocket. Late tonight, at 11:02 pm local time in California (06:02 UTC Wednesday), SpaceX has a chance to reach 200 successful launches with a Starlink mission lifting off from Vandenberg Space Force Base. Given the late hour, and weather permitting, this launch should provide some great viewing opportunities along the California coast tonight.

Such a performance is in uncharted territory for any orbital rocket, ever. According to Wikipedia, the Soyuz-U rocket had a streak of 112 consecutive successful launches between July 1990 and May 1996. However this period included the Cosmos 2243 launch in April 1993. This mission should more properly be classified as a failure. According to space scientist Jonathan McDowell, the control system of the rocket failed during the final phase of the Blok-I burn, and the payload was auto-destructed.

Taking this failure into account, the Soyuz-U had a run of 100 successful launches from 1983 to 1986. This happens to be the exact same number of consecutive successes by the Delta II rocket, originally designed and built by McDonnell Douglas and later flown by Boeing and United Launch Alliance. Overall the Delta II rocket launched 155 times, with two failures. Its final flight, in 2018, was the rocket's 100th consecutive successful mission.

So with tonight's launch, SpaceX is setting itself up to double the record for the number of consecutive successes by an orbital rocket.