Scattering cremated remains in the sea or even burying them with planted trees have long been popular ways to send off the dead, but now loved ones can be remembered with a shooting star-like farewell, a journey to the moon or even an eternal voyage through deep space.

Thanks to a growing number of space burial services, taking life's symbolic final stage out of this world is not just science fiction. For Tomoko Kasai, a veteran of over three decades in the funeral industry and founder of a rare Japanese company offering such services, imagination is becoming a reality.

"I had been (in the funeral business) for 20 years but felt something was lacking. Then I remembered that as a child I wanted to become a star when I died, and got the idea of doing space burials. But I knew from the start that it couldn't be done in Japan," the 62-year-old said.

Kasai, who founded Space NTK in 2017, sought ways to realize her dream by traveling to the United States to give an impassioned speech at a space industry conference. There she met a Japanese engineer of SpaceX, the groundbreaking rocket and spacecraft maker founded by Elon Musk, and her plans were set into motion.

Photo taken Feb. 13, 2023, shows Tomoko Kasai, founder of Space NTK. (Kyodo)

In the summer of 2020, Kasai received a call from none other than Musk -- or rather, his Japanese-speaking representative at SpaceX.

"I was told, Mr. Elon is next to me right now, and would like to help you scatter ashes in space. I was happy just being able to send a portion of a person's ashes, but Mr. Elon said a whole body's worth was also possible since (SpaceX's) rocket was big. Since Mr. Elon suggested it, I decided to do it," Kasai said.

Kasai soon signed a contract to put payloads aboard Falcon 9 as part of SpaceX's SmallSat Rideshare Program, and in April 2022 Space NTK successfully conducted the first launch of its Magokoro satellite, jettisoning the remains of five people and five pets, as well as DNA and messages, around 500 to 600 kilometers above the Earth's surface, where they currently remain in orbit.

Space burials at Space NTK start at 550,000 yen ($4,000) for up to 50 grams of ashes, with a whole human body's worth of ashes, roughly 2 kilograms, starting from 7.7 million yen. The company also caters to pets.

Maki Tamura, whose rescue dog Isshin was among the ashes on board the April 2022 launch, said she wanted to use the unusual method of space burials to raise awareness for shelter dogs. But the poignant symbolism offered her comfort as well.

Ashes, DNA and messages sent to space in April 2022's launch are a shown inside one of Space NTK's Magokoro boxes. (Photo courtesy of Space NTK)(Kyodo)

"By returning (Isshin) to the grand nature that is the universe, I feel like we will meet again after I die," Tamura said. "I now feel like I am being watched over by a beloved member of my family every time I look up at the night sky."

With Space NTK's next launch planned for late 2023, Kasai said she makes sure to personally take her customers' ashes to the United States, staying until the very last possible moment to ensure everything is in order.

"It is, of course, a huge responsibility that I cannot entrust to anyone else. As long as I am alive, I will take (the ashes) there personally," Kasai said.

After the rocket is launched and its second stage placed in Earth's orbit with the satellite attached, customers can see the position of their loved ones in real-time using a provided QR code. That is, until it reenters the atmosphere and burns up like a shooting star -- a journey that takes around five to seven years.

While this type of space burial does not add to the space junk problem above Earth, it could still cause issues as demand for unique end-of-life experiences continues to grow.

Image from Space Perspective's homepage shows a rendition of the interior of the company's spaceship. (Photo courtesy of Space NTK)(Kyodo)

"Even if the remains are not in orbit for long, if hundreds or thousands of space burials are performed a year, those remains could very well constitute dangerous space debris," said Alexander Wagner, an assistant professor in astrophysics at the University of Tsukuba's Center for Computational Sciences.

One possible consequence of increased space debris is accelerating the degradation of the James Webb Space Telescope, which is "regularly pummeled by 'micrometeoroids'," he said.

But launching ashes to orbit above Earth is not the only space burial service on offer, with Space NTK also partnering with U.S. firm Space Perspective to hold living funerals -- known as "seizenso" in Japan.

This form of ceremony, held for an individual while they are still alive, is chosen by some elderly Japanese to lift the burden on their children of organizing a funeral after they die.

Kasai said that Space NTK has already reserved 64 seats with Space Perspective for trips in 2026 and 2027 to hold such funerals. The package, starting from $175,000 per person, includes the roundtrip flight to the United States for launch in Florida, a luxury hotel stay, and full Japanese-language support.

Unlike rockets, no special training is needed to ride in the stratospheric balloon-borne capsule that will take passengers on a six-hour trip to the edge of space above 99 percent of Earth's atmosphere and back.

"Anybody that is physically able to fly to the United States can go on this trip. People can go as a family, or even hold a wedding ceremony on board," said Kasai.

Tomoko Kasai in front of SpaceX’s Falcon 9 rocket at Cape Canaveral, Florida, a day before launch on March 31, 2022. (Photo courtesy of Space NTK)(Kyodo)

Space NTK is also currently accepting bookings for lunar burials to be held in late 2023 in collaboration with a Japanese company developing a moon rover -- something that has only been achieved by U.S. spaceflight company Celestis Inc. to date.

Celestis, which has completed memorial spaceflights for more than 1,000 families from over 20 countries since introducing the services in 1997, also plans to launch the first-ever memorial spaceflight to deep space as early as May 2023 with United Launch Alliance's new Vulcan rocket, according to the company.

"The Enterprise Flight carrying its ashes, DNA, and Celestis MindFiles will be the first true outpost of humanity beyond the Earth-Moon system," a company spokesperson said.

Among the flight capsules that will enter a stable orbit around the Sun will be the ashes of Star Trek creator Gene Roddenberry and his wife Majel, and Philip Chapman, the first Australian-born astronaut and a mission scientist for Apollo 14, according to a press release.

While the capsules will, in essence, embark on an eternal journey through interplanetary space, the universe and time will decide their fate. Wagner said that due to energy losses in the real world, "a real equilibrium, such as an indefinitely stable orbit, never really exists."

Still, for Kasai, the allure of space has not waned since childhood. Her dream of having her ashes sent into the grand vastness after she dies remains unchanged.

"In the end, I want to return to my place of origin. And I believe that place is not the earth or the sea, but the universe," she said.

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