A Look at 10 Million Stars Finds No Sign of Life Yet
Scientists have completed the largest search to date for signs of life outside of our solar system.
Using a radio telescope in Australia, scientists studied around 10.3 million stars. They did not find life - not yet, at least.
Researchers were looking for so-called "technosignatures" - communications signals that may come from alien beings.
Using the Murchison Widefield Array (MWA) telescope in Western Australia, scientists searched for sound waves in the star system of Vela. The findings were published recently in Publications of the Astronomical Society of Australia.
Chenoa Tremblay is an astrophysicist with Australia's national science agency. Tremblay noted that the findings were "not surprising."
"The search for life outside of our solar system is a big challenge," Tremblay added. "We don't know when, how, where or what type of signal we may receive to get an indication that we are not alone in the galaxy."
The search was 100 times deeper and broader than ever before, noted astrophysicist Steven Tingay of Curtin University in Australia. Still, it involved few stars in the universe.
"Ten million stars does seem like a lot. However, our best evaluation is that there are around 100 billion stars (in the Milky Way galaxy). So we have only looked at about 0.001% of our galaxy," Tremblay said. "Pretend the oceans contained only 30 fish and we tried to look for them by testing an area the size of a backyard swimming pool. The chances of finding one of those fish would have been small."
Another kind of telescope, the Square Kilometer Array (SKA), promises to help search for technosignatures soon.
"What is important is ... always going deeper and further," Tingay said. "There is always that chance that the next observation will be the one that turns up something, even if you expect nothing. Science can be surprising, so the important thing is to keep looking."
I'm John Russell.
1.backyard n. 后院
He had an assemblage of old junk cars filling the backyard.
2.universe n. 宇宙；世界
Behind his eyes was a whole universe of pain.
The telescope has a magnification of 50.
You mustn't fire without my signal.
5.There is always that chance that the next observation will be the one that turns up something, even if you expect nothing.
turn up 出现；发生
Richard had turned up on Christmas Eve with Tony.
Investigations have never turned up any evidence.
6.They did not find life - not yet, at least.
at least 至少
He's been away for at least a week.
This jury is expected to be sequestered for at least two months.
利用澳大利亚的电波望远镜，科学家们研究了大约1030万颗恒星 。他们没有发现生命迹象，至少目前没有 。
利用澳大利亚西部的默奇森宽场阵列（MWA）望远镜，科学家们在Vela星座周围搜寻声波 。这一发现最近发表在《澳大利亚天文学会出版物》上 。
希诺阿·特伦布雷（Chenoa Tremblay）是澳大利亚国家科学机构的天体物理学家 。特伦布雷指出，研究结果“并不意外 。
特伦布雷补充说，“在太阳系外寻找生命是一项巨大的挑战” 。“我们不知道何时、何地、以何种方式或者接收到什么样的信号，来证明我们在银河系中并不是孤单的 。”
澳大利亚科廷大学的天体物理学家史蒂夫·廷加（Steven Tingay）指出，这次搜寻的深度和广度是以往的100倍 。即便如此，研究涉及到宇宙中的恒星还是很少 。
特伦布雷说，“1000万颗恒星看起来确实很多 。然而，我们最保险的评估是（在银河系）大约有1000亿颗恒星 。所以说，我们只观察到银河系的0.001% 。”“假设汪洋大海里只有30条鱼，我们搜寻的范围大概是后院游泳池大小的区域 。所以找到这样一条鱼的概率很小 。”
“重要的是……研究会越来越深入、广泛 。”“即使你无所期待，但是下一个观察结果总是有可能出现一些结果的 。科学是会令人惊讶的，所以重要的是继续寻找 。”