Visions of life on Mars in Earth’s depths
Bacteria that live deep within the Earth’s crust are giving scientists insights into where life could exist elsewhere in the solar system, including Mars
By Kenneth Chang / NY Times News Service
More than a kilometer down in an unused mine tunnel, scientists guided by helmet lamps trudged through darkness and the muck of a flooded, uneven floor.
In the subterranean world of the Beatrix Gold Mine, they shed their backpacks, took out tools and meticulously prepared test tubes to collect samples.
Leaning a ladder against the hard rock wall, Tullis Onstott, a geosciences professor at Princeton University, climbed to open an old valve about 3.66m up.
Out flowed water chock-full of microbes, organisms flourishing not from the warmth of the sun, but by heat generated from the interior of the planet below.
These tiny life-forms — bacteria, other microbes and even little worms — exist in places nearly impossible to reach, living in eternal darkness, in hard rock.
Scientists like Onstott have been on the hunt for life in the underworld, not just in South Africa, but in mines in South Dakota and at the bottom of oceans.
What they learn could provide insights into where life could exist elsewhere in the solar system, including Mars.
Microbial Martians might well look like what lives in the rocks in the deep underground mine.
The same conditions almost certainly exist on Mars. Drill a hole there, drop these organisms in, and they might happily multiply, fueled by chemical reactions in the rocks and drips of water.
“As long as you can get below the ice, no problems,” Onstott said. “They just need a little bit of water.”
Mars has long been a focus of space exploration and science fiction dreams. NASA has sent more robotic probes there than any other planet. However, now there is renewed interest in sending people as well. NASA has been enthusiastically promoting its “Journey to Mars” goal to send astronauts there in the 2030s. Elon Musk, the billionaire founder of SpaceX, is promising that he will be able to get there a decade sooner and set up colonies.
Astronauts on Mars would be able to greatly accelerate the quest for answers to the most intriguing questions about the red planet. Was there ever life on Mars? Could there be life there today?
It was not that long ago that scientists had written off Mars as lifeless.
Forty years ago, NASA spent about US$1 billion on its Viking program, which revealed a cold, dry world seemingly devoid of organic molecules that are the building blocks of life.
However, more recent missions have discovered compelling evidence that Mars was not always such an uninviting place. In its youth, more than 3 billion years ago, the planet was warmer and wetter, blanketed with a thick atmosphere — possibly almost Earthlike.
A fanciful, but plausible notion is that life did originate on Mars, then traveled to Earth via meteorites, and we are all descendants of Martians.
Eventually, Mars did turn cold and dry. Radiation broke apart the water molecules and the lighter hydrogen atoms escaped to space. The atmosphere thinned to wisps.
However, if life did arise on Mars, might it have migrated to the underworld and persisted?
For a couple of decades, Onstott has been talking his way into South African gold mines, regaling the mine managers with the wonder of deep-Earth life to overcome their wariness. In many ways, the mines provide easy access to the depths — a ride in a cage-like elevator, jammed against miners starting their shift, descending quickly as lights from the different levels zip past. Think of it as traveling through a 450-story skyscraper, going down.
http://www.taipeitimes.com/News/editorials/archives/2016/09/16/2003655234
More than a kilometer down in an unused mine tunnel, scientists guided by helmet lamps trudged through darkness and the muck of a flooded, uneven floor.
In the subterranean world of the Beatrix Gold Mine, they shed their backpacks, took out tools and meticulously prepared test tubes to collect samples.
Leaning a ladder against the hard rock wall, Tullis Onstott, a geosciences professor at Princeton University, climbed to open an old valve about 3.66m up.
Out flowed water chock-full of microbes, organisms flourishing not from the warmth of the sun, but by heat generated from the interior of the planet below.
These tiny life-forms — bacteria, other microbes and even little worms — exist in places nearly impossible to reach, living in eternal darkness, in hard rock.
Scientists like Onstott have been on the hunt for life in the underworld, not just in South Africa, but in mines in South Dakota and at the bottom of oceans.
What they learn could provide insights into where life could exist elsewhere in the solar system, including Mars.
Microbial Martians might well look like what lives in the rocks in the deep underground mine.
The same conditions almost certainly exist on Mars. Drill a hole there, drop these organisms in, and they might happily multiply, fueled by chemical reactions in the rocks and drips of water.
“As long as you can get below the ice, no problems,” Onstott said. “They just need a little bit of water.”
Mars has long been a focus of space exploration and science fiction dreams. NASA has sent more robotic probes there than any other planet. However, now there is renewed interest in sending people as well. NASA has been enthusiastically promoting its “Journey to Mars” goal to send astronauts there in the 2030s. Elon Musk, the billionaire founder of SpaceX, is promising that he will be able to get there a decade sooner and set up colonies.
Astronauts on Mars would be able to greatly accelerate the quest for answers to the most intriguing questions about the red planet. Was there ever life on Mars? Could there be life there today?
It was not that long ago that scientists had written off Mars as lifeless.
Forty years ago, NASA spent about US$1 billion on its Viking program, which revealed a cold, dry world seemingly devoid of organic molecules that are the building blocks of life.
However, more recent missions have discovered compelling evidence that Mars was not always such an uninviting place. In its youth, more than 3 billion years ago, the planet was warmer and wetter, blanketed with a thick atmosphere — possibly almost Earthlike.
A fanciful, but plausible notion is that life did originate on Mars, then traveled to Earth via meteorites, and we are all descendants of Martians.
Eventually, Mars did turn cold and dry. Radiation broke apart the water molecules and the lighter hydrogen atoms escaped to space. The atmosphere thinned to wisps.
However, if life did arise on Mars, might it have migrated to the underworld and persisted?
For a couple of decades, Onstott has been talking his way into South African gold mines, regaling the mine managers with the wonder of deep-Earth life to overcome their wariness. In many ways, the mines provide easy access to the depths — a ride in a cage-like elevator, jammed against miners starting their shift, descending quickly as lights from the different levels zip past. Think of it as traveling through a 450-story skyscraper, going down.
http://www.taipeitimes.com/News/editorials/archives/2016/09/16/2003655234
*Structure of the Lead：
WHO-scientists
WHEN-not given
WHAT- guided by helmet lamps trudged through darkness and the muck of a flooded, uneven floor
WHY- not given
WHERE-not given
HOW-not given
*Keywords：
1. trudge：跋涉，步履艱難地走
SYN：plod, lumber, tramp
2. muck：腐殖土；淤泥
3. uneven：不平坦的，崎嶇的；參差不齊的
SYN：unequal, irregular, disparate；ANT：even
4. subterranean：地下的
5. shed ：把……放入棚內
6. take out： 取出; 請人...
SYN：get out
7. meticulously ：極注意地，極細心地，一絲不苟地
8. valve ：閥; 閘閥; 氣門
9. interior ：內部，內側
SYN：inside, inner, middle, heart；ANT：exterior, foreign
10. eternal ：永久的，永恆的；無窮的
SYN：endless, perpetual, everlasting, permanent；ANT：momentary, temporary,
transient
11. multiply ：使（成倍地）增加
SYN：increase, advance, gain, grow；ANT：divide
