Amazon billionaire Jeff Bezos’ Blue Origin venture is getting ready for launch. (Blue Origin Photo)

All eyes are on Elon Musk as his company SpaceX gets ready to launch its first Falcon Heavy rocket from NASA’s Kennedy Space Center in Florida as early as Tuesday, and fellow wealthy space enthusiast Jeff Bezos is also paying attention.

Bezos, Amazon CEO and founder of his own space venture, Blue Origin, tweeted good luck to SpaceX as it prepares to launch what is designed to be the world’s most powerful operational rocket.

Musk responded with an equally gracious tweet, including a kissing-heart emoji:

The two billionaires haven’t always been on such cordial terms: In November 2015, when Bezos tweeted with pride that Blue Origin had produced “the rarest of beasts – a used rocket,” Musk replied sourly that Blue Origin’s New Shepard suborbital spaceship was “not quite ‘rarest.'”

“SpaceX Grasshopper rocket did 6 suborbital flights 3 years ago & is still around,” Musk wrote.

An argument over suborbital spaceflight vs. orbital spaceflight ensued among Bezos’ and Musk’s fans. Eventually, the feud cooled down as both SpaceX and Blue Origin met with different variants of space success, focusing on greater and greater rocket reusability.

Those who fellow Bezos’ space venture will recognize the hashtag at the end of today’s tweet, “Gradatim Ferociter,” which is Latin for “Step by Step, Ferociously.” Bezos has said the phrase represents his approach to spaceflight. “If you’re building a flying vehicle, you can’t cut any corners. If you do, it’s going to be [just] an illusion that it’s going to make it faster. … You have to do it step by step, but you do want to do it ferociously.”

Should the Falcon Heavy launch prove successful, it will be more than a small step in the field, which is currently being advanced by space-minded billionaires like Bezos and Musk.

This week’s first test launch is due to take place at the historic Launch Complex 39A at NASA’s Kennedy Space Center in Florida, which previously served as the site of liftoffs for moon rockets and space shuttles.

Falcon Heavy will have more payload-to-orbit capacity than any rocket since the Apollo era’s Saturn V, and could eventually be used to send payloads to the moon and Mars as well. For this first test run, the Falcon Heavy is due to send Musk’s red Tesla Roadster sports car on a flight of fancy ranging out as far as the orbit of Mars.

But success isn’t assured: Last year, Musk noted that “there’s a lot that could go wrong” with the launch, and there’s no getting around the fact that failure in the form of a huge explosion is an option.

“Guaranteed to be exciting, one way or another,” he said.

GeekWire’s Alan Boyle contributed to this report.

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