Billionaire Sir Richard Branson managed to reach the horizon using his Virgin Galactic rocket plane.
The British entrepreneur flew over New Mexico in the United States in a special ascent car that his company has been repairing for 17 years.
The trip, he said, "is a big step in life".
He is now safe on earth with his staff.
It makes him one of the pioneers of space tourism and surpasses Tesla's Elon Musk and Amazon's Jeff Bezos.
We are awaiting official confirmation of the height reached by Sir Richard, but it appears to have been 85km (282,000ft; 53 miles).
He was in the caravan with two Unity pilots, Dave Mackay and Michael Masucci, and three Galactic crew members - Beth Moses, Colin Bennett, and Sirisha Bandla.
Sir Richard paid for the flight as a test of the experience of aerospace tourism and hopes to start selling tickets to customers from next year.
Some 600 people have already paid a deposit for tickets that will cost them up to $ 250,000.
These are all people who want to reach a height where they can see the sky as black and marvel at the horizon as the Earth rotates in the distance. Such a plane should also give them about five minutes of weight loss when they will be allowed to float inside the Unity device.
It has been a long journey for Sir Richard to reach this point. He first announced his intention to build a spacecraft in 2004, believing he could start the commercial service by 2007.
But technical difficulties, as well as serious accidents during a pilot flight in 2014, have made the space shuttle project one of the most difficult projects in its profession.
"I have wanted to go to space since I was a child, and I want to enable hundreds of thousands of other people in the next 100 years to go to space," Sir Richard told the BBC ahead of Sunday's trip.
"And why don't they go to the sky? A sky is a wonderful place; The world is beautiful. I want people to be able to look at our beautiful world and come home and work hard to take care of it."
Aviation tourism is a place that is revived after ten years and is about to find a lot of competition.
In the 2000s, seven rich people paid to visit the International Space Station (ISS). But the missions, organized under the auspices of the Russian space agency, ended in 2009.
Now, new plans abound. Along with Sir Richard's initiative, there are projects undertaken by Amazon.com founder Jeff Bezos and technology entrepreneur from California Elon Musk.
The Russians, too, are returning their commercial aircraft to the ISS, and there are even those who want to launch private airports to visit. Among these is Axiom, a company founded by a former Nasa ISS planning manager.
Mr. Richard received a message of goodwill from Mr. Bezos on Saturday
The day before, Mr. Bezos' Blue Blue space company released a Twitter message that appeared to mock Unity's Virgin Galactic spacecraft. The message reiterated that anyone who flew on the rocket would have an eternal star in his name because he could not reach "international recognition" at the point where the sky begins - the so-called Kármán 100km Line.
The US government, however, has been recognizing the space limit to be around 80km (50 miles) and recognizes anyone who exceeds this height. Before Sunday, only 580 people had ever been on this height.
Unity is a small rotating car. This means that it cannot reach the speed and height necessary to place it in space around the globe.
The car is designed to give its passengers a great opportunity to see the world from above.
Unity is first taken by the largest aircraft at a distance of about 15km (50,000ft), where it is delivered.
A special car behind the Unity rocket then ignites and propels it into the sky at high speed.
The maximum reach of Unity is approximately 90km (55 miles, or 295,000ft). Passengers are allowed to open their belts to float to the window.
