VAN HORN, Texas — An isolated edge of vast West Texas is home to a highly secretive part of the 21st-century space race, one of two being directed in the Lone Star State by Internet billionaires whose personalities and corporate strategies seem worlds apart.

The presence of Blue Origin, LLC, the brainchild of Amazon founder Jeff Bezos, barely registers in nearby Van Horn, a way station along Interstate 10, a full decade after he began buying land in one of Texas’ largest counties.

Few visitors are allowed beyond the “No Trespassing” sign and a remote-controlled gate and into the desert and mountain environment reminiscent of the Air Force’s renowned Area 51 in Nevada. The privileged who do get inside decline to describe what they’ve seen, typically citing confidentiality agreements.

“No one gets in other than employees,” says Robert Morales, editor of the weekly Van Horn Advocate newspaper.

At the opposite end of Texas is the highly visible SpaceX venture, led by PayPal co-founder and electric car maker Elon Musk. His company contracts with NASA to resupply the International Space Station and is building a launch site about 600 miles from Van Horn, on the southernmost Texas Gulf coast, with the much-publicized goal of sending humans to Mars.

SpaceX and Blue Origin are among several U.S. companies engaged in the private space business. Both men have seemingly unlimited resources – Bezos’ wealth is estimated at nearly $35 billion, Musk’s at $12 billion – and lofty aspirations: launching a new era of commercial space operations, in part by cutting costs through reusable rockets.

Texas’ glory days of space exploration, when “Right Stuff” Mercury astronauts trained in Houston and the city’s name was the first word spoken on the moon by Neil Armstrong, are long gone. The utilitarian space shuttle fell to budget cuts, depletion and age, leaving astronauts to hitch rides on Russian rockets.

But this month, Bezos announced that his company’s new hydrogen rocket engine, designed for suborbital missions, had completed hundreds of tests at the West Texas site, adding, “soon we’ll put it to the ultimate test of flight.” That could come late this year.

A more powerful engine for orbital flights, fueled by liquid oxygen and liquid natural gas, is being developed with United Launch Alliance, a venture of aerospace veterans Boeing Co. and Lockheed Martin Corp.

Bezos’ love of space originated in Texas in the 1960s when his family moved to Houston, which dubbed itself “Space City USA.”

“For me, space is something that I have been in love with since I was 5 years old,” Bezos, 51, said in a September interview with The Washington Post, which he purchased in 2013. “I watched Neil Armstrong step onto the surface of the moon, and I guess it imprinted me.”

Over the last decade, he has bought at least seven ranches, totaling 1,900 square miles, near the Texas-New Mexico border and Guadalupe Mountains National Park.