of trees have been to the Moon. How they got there and back again
is a curious tale.
by Dr Tony Phillips
Scattered around our planet are hundreds
of living things that have been to the Moon and back again. None
of them are human. They outnumber active astronauts 3:1. And most
They're trees. "Moon Trees."
NASA scientist Dave Williams has found
40 of them and he's looking for more. "They were just seeds when
they left Earth in 1971 onboard Apollo 14," explains Williams. "Now
they're fully grown. They look like ordinary trees - but they're
special because they've been to the Moon."
How they got there and back is a curious
It begins in 1953 when Stuart Roosa
parachuted into an Oregon forest fire. He had just taken a summer
job as a US Forest Service "smoke jumper," parachuting into wildfires
in order to put them out. It was probably adventure that first attracted
Roosa to the job, but he soon grew to love the forests, too. "My
father had an affinity for the outdoors," recalls Air Force Lt.
Col. Jack Roosa, Stuart's son. "He often reminisced about the tall
Ponderosa pine trees from his smoke jumping days."
Thirteen years later, NASA invited
Roosa, who had since become an Air Force test pilot, to join the
astronaut program. He accepted. Roosa, Ed Mitchell and Al Shepard
eventually formed the prime crew for Apollo 14, slated for launch
"Each Apollo astronaut was allowed
to take a small number of personal items to the Moon," continued
Jack. Their PPKs, or Personal Preference Kits, were often filled
with trinkets - coins, stamps or mission patches. Al Shepard took
golf balls. On Gemini 3, John Young brought a corned beef sandwich.
"My father chose trees," says Jack. "It was his way of paying tribute
to the US Forest Service."
The Forest Service was delighted.
"It was part science, part publicity
stunt," laughs Stan Krugman, who was the US Forest Service's staff
director for forest genetics research in 1971. "The scientists wanted
to find out what would happen to these seeds if they took a ride
to the Moon. Would they sprout? Would the trees look normal?" In
those days biologists had done few experiments in space; this would
be one of the first. "We also wanted to give them away as part of
the Bicentennial celebration in 1976."
Krugman himself selected the varieties:
Redwood, Loblolly pine, Sycamore, Douglas Fir and Sweetgum. "I picked
redwoods because they were well-known, and the others because they
would grow well in many parts of the United States," he explained.
"The seeds came from two Forest Service genetics institutes. In
most cases we knew their parents (a key requirement for any post-flight
On January 31, 1971, Apollo 14 blasted
off. Only Shepard and Mitchell actually walked on the Moon. On Feb.
5th they landed the lunar module Antares in Fra Mauro - a
hilly area where Shepard famously launched his golf balls using
a geology tool as a makeshift driver. Roosa remained in orbit as
pilot of the mission's command module Kitty Hawk. Inside
his PPK was a metal cylinder, 6 inches long and 3 inches wide, filled
with seeds. Together they circled the Moon 34 times.
Apollo 14 was a success. Scientists
were delighted with the mission's geology experiments and they were
eager to study the 43 kg of Moon rocks collected by Shepard and
Mitchell. Krugman was just as eager to study the seeds.
"We had a bit of a scare," Krugman
recalls. During decontamination procedures, the seed canister was
exposed to vacuum and it burst. The seeds were scattered and traumatized.
"We weren't sure if they were still viable," he says. Working by
hand, Krugman carefully separated the seeds by species and sent
them to Forest Service labs in Mississippi and California. Despite
the accident, nearly all of them germinated. "We had [hundreds of]
seedlings that had been to the Moon!" Thirty-one years later, Krugman
still sounds excited.
During the years that followed, the
trees thrived as scientists watched. "The trees grew normally,"
he continued. "They reproduced with Earth trees and their offspring,
called half-Moon trees, were normal, too." (He notes, however, that
DNA analysis wasn't routinely done in the early '70's, and so the
Moon trees weren't tested in that way. There might be subtle differences
yet to be discovered.)
tree at the NASA Goddard Space Flight Centre.
Finally, in 1975, they were ready to
leave the lab. "That's when things got out of hand," he says.
Everyone wanted a Moon tree. In 1975
and '76, trees were sent to the White House, to Independence Square
in Philadelphia, to Valley Forge. "One tree went to the Emperor
of Japan. Senators wanted trees to dedicate buildings. We even did
some plantings in New Orleans because the mayor there, Mayor Moon,
wanted some," says Krugman. There were so many requests that "we
had to produce additional seedlings from rooted cuttings of the
No one kept systematic records, notes
Dave Williams. That's why the whereabouts of the trees today are
One of the them went to a Girl Scout
camp in Cannelton, Indiana, where 3rd grade teacher Joan Goble found
it in 1996. (She knew it was a Moon Tree because a sign said so.
Most Moon trees were planted with ceremony; there's usually a sign
or plaque nearby that identifies them.) "My students love it," she
says. "It looks like an ordinary tree, but they feel it's special
anyway because of its trip to the Moon." Jack Roosa has since become
a pen pal of Goble's class, encouraging the students to explore
and learn as his father did.
When Goble contacted Dave Williams
to ask for more information about Moon trees, "I was clueless,"
Williams admits. Like many people who were young in the 1970's,
Williams had never heard of such trees, but he soon became an enthusiast.
"I found one Moon tree right here at Goddard near my office," he
laughs. "I had no idea it was there."
Often that's how they're encountered - by
accident. Williams now maintains a web
site listing all known Moon trees. If you stumble across one
then contact him. He'll investigate the find and add it to the collection
if it's authentic.
Moon trees are long-lived, adds Krugman.
The redwoods could last thousands of years, and the pines have a life
expectancy of centuries. Indeed, they've already outlived Stuart Roosa
and Al Shepard - two of the humans who took them to the Moon.
in Goble's 3rd grade class made this sign for their Moon
tree in Indiana.
Says Jack, "I think my father always knew that these
trees would serve as a long-lasting, living reminder of mankind's
greatest achievement - the manned missions to the Moon." Of course,
if humans don't return soon, Moon trees could become the only
living things on our planet that have been to the Moon. That's probably
not what Stuart had in mind.
Jack, however, is optimistic: "These trees will
be here 100 years from now," he says. "By then I believe we'll be
planting Mars trees right beside them."