New life found on old rock

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In 1995, NASA was strapped for cash — and the search for life beyond Earth looked like it might be in trouble.

Years of drastic cuts had slashed the space agency’s five-year budget plan by just over 30 percent. Interest in exobiology—the study of the origin, evolution, and spread of life in the universe—had dried up for decades. After the 1976 Viking lander life search experiment on Mars came up empty, NASA scaled back missions to Mars. Congress canceled NASA’s search for extraterrestrial intelligence program in 1993 after less than a year of operation. And in 1995, the Clinton administration called for more than $5 billion in additional funding cuts to NASA before the new millennium.

“Then a miracle called ALH84001 happened,” said Wesley Huntress, then NASA’s associate administrator for space science. “And that just drives public interest in what we’re doing.”

A potato-sized chunk of 4-billion-year-old gray-green rock from Mars, ALH84001, fell to Earth about 13,000 years ago. Researchers found it in the Allen Hills region of Antarctica during a 1984 meteorite search expedition and brought it to the Johnson Space Center (JSC) Meteorite Processing Laboratory, where the Martian origin of the rock was discovered almost a decade later in 1993

ALH84001 is not just a Martian meteorite. It contains carbonate minerals—minerals that on Earth can be formed by life—that JSC researchers believe evolved at habitable temperatures. Under an electron microscope, the tiny structures in the carbonates looked like images of nanobacteria buried in a hot spring mineral deposit on Earth. These carbonates weren’t enough to prove anything on their own, but they hinted that ALH84001 might be much more than just another space rock. So in 1994, a JSC-led team quietly got to work taking a closer look at the meteorite.

Revived search

Two years later, on August 7, 1996, NASA announced that JSC researchers believed ALH84001 contained traces of ancient microbial life from Mars.

Suddenly, the quest for life returned. That same day, President Bill Clinton went on television to promise that NASA would “put its full intellectual might and technological prowess into the search for further evidence of life on Mars.” A few days later, a headline reading “After Mars Rock, Hunt for Otherworldly Organisms Revived” topped the science section of New York Times. By September, NASA’s Ames Research Center brought together nearly 100 astronomers, Earth scientists and biologists for the first-ever scientific conference on astrobiology, a successor to exobiology that takes a broader look at the search for life in the universe. And in December, Vice President Al Gore met with leading scientists to discuss the implications of finding evidence of extraterrestrial life and chart a course for NASA’s future exploration of Mars.

Astrobiologist Jamie Foster of the University of Florida watched these events unfold. A young Dr. student at the University of Hawaii in 1996, Foster had always dreamed of working for NASA, but was instead working in a zoological lab when ALH84001 hit the news.

“I remember President Clinton at the time going on TV and talking about this rock — you know, talking about the exciting potential: Has life from Mars been found in this meteorite?” Foster says. “Now we know it’s very, very controversial, … but what it did was it allowed funding to be absorbed.”

Traveling from Mars 13,000 years ago, ALH84001 landed in the Allen Hills of Antarctica (Credit: tunasalmon/Shutterstock).

Embracing Astrobiology

Earlier, it was clear that the meteorite would have financial stakes. Huntress remembers getting a call shortly after ALH84001 hit the headlines from Steve Isakowitz, then chief of the space programs branch of the White House Office of Management and Budget. Isakowitz wanted to know how NASA should benefit from the discovery. “The president’s Office of Management and Budget came in and said, ‘What do you want to do with this Mars rock?'” Huntress says. “We had a plan right in our back pocket called Origin.”

The Origins program has been in development since at least 1994. The idea was to unite many of NASA’s myriad space science missions behind one grand unifying theme: understanding the origin, distribution, and future of life in the universe. Before ALH84001, Origins “was just a blueprint,” says Huntress. But after much back and forth between Isakowitz and Huntress, it became much more.

The president’s fiscal year 1998 NASA budget proposal calls for a staggering $1.5 billion more in space science funding between 1998 and 2000 than in the 1996 proposal. The plans for additional, large cuts of billions of dollars to the total NASA budget through the year 2000 were canceled; NASA’s budget would still shrink slightly, but space science, and above all astrobiology, was in for a renaissance.

Citing the discovery of putative biosignatures in ALH84001 as motivation for the new funding, the 1998 budget allowed cash infusions for the search for life. It funded new missions to discover exoplanets, including the next-generation space telescope — eventually renamed the James Webb Space Telescope — which launches in December 2021. It also committed money to a new program to develop technologies for exploring the solar system and increased funding for the Mars Surveyor program with the goal of one day returning a sample from Mars, a mission the Perseverance rover is carrying out today.

Origins also funded a new program in astrobiology, which became the Ames-led NASA Astrobiology Institute (NAI). Enjoying a wave of new funding and the growing scientific legitimacy of astrobiology, NASA is welcoming biologists into space science with renewed enthusiasm.

Foster was one of those biologists. More than 20 years later, she is a professor at the University of Florida’s Space Life Science Laboratory, where she studies modern analogues of microbial ecosystems that were common on early Earth and how spaceflight affects animals and their microbiomes.

For her, the sudden surge in funding, institutional support and interest in astrobiology made it possible to pursue a career that would have been nearly impossible just a few years earlier. “The meteorite created doors that never existed before,” she says.

ALH84001 wasn’t the only factor that pushed NASA to embrace astrobiology in the mid-1990s. “It was the confluence of many things at once, creating a perfect storm for studying life in the universe,” says Lynn Harper, who was one of the heads of astrobiology at Ames between 1995 and 2003. “The Allen Hills meteorite itself is not provided the financing [for the NAI],” she says. It was certainly in the mix. But it wasn’t going to be enough.

Harper sees the aggressive internal audit, called the Zero Base Review, as more important to the development of astrobiology at NASA. The zero-base review was launched in 1995 in response to NASA’s drastically shrinking budget as a way to eliminate or restructure inefficient programs. The space agency had to downsize, and Ames — long home to an unusual interdisciplinary cadre of respected exobiologists — found its science programs at rock bottom.

Today, the Perseverance rover continues its search for evidence of life on Mars (CC BY-SA 3.0 IGO; NASA/JPL-Caltech).

Unlike other NASA centers, such as the Jet Propulsion Laboratory, which leads NASA in planetary science, Ames’ mix of researchers who have studied everything from planetary atmospheres to life in extreme environments has made their role at NASA difficult to define. But Ames’ leadership knew their exobiological hot spot was something worth saving. So instead of coming up with the decommissioning plan they were asked to do, they argued that the center does serve several purposes, including searching for life in the universe and understanding how life originates. It worked, which is why Ames eventually became NASA’s flagship center for astrobiology.

And ALH84001 wasn’t the only discovery of the 1990s that revived interest in the search for life. Hubble began sending dazzling images of space in 1990. The first exoplanet was discovered in 1992, and the Galileo probe’s flyby of Europa, which began in 1996, hinted that the icy moon might harbor an ocean. Some of these findings are highlighted along with ALH84001 in the budget request that funded Origins.

Today, the scientific community agrees that the possible biosignatures in ALH84001 are not that convincing. Even in 1996, researchers expressed skepticism about the findings. The “Mars Rock” was one of the greatest scientific discoveries that never happened. However, this rock renewed NASA’s search for life, which continues today.

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