周三是世界地球日50周年。美国人盖洛德·尼尔森于1970年发起了第一个世界地球日。他的目的是督促当地采取行动，并加深人们对地球及其环境的了解。
The creation of Earth Day is widely considered the beginning of the modern environmental movement.
地球日的创设被广泛认为是现代环保运动的开始。
As climate activists marked the event this year, an unplanned experiment is changing the planet.
当气候活动家纪念今年的地球日时，一项意外实验正在改变地球。
Many people continue to stay at home to stop the spread of the new coronavirus. As a result, people are making less pollution, and the air has become cleaner.
很多人继续留在家里以阻断新冠病毒的传播。结果，人类造成的污染减少了，空气变得更加清洁。
Smog stopped covering New Delhi, one of the world's most polluted cities. Nitrogen dioxide pollution in the northeastern United States has dropped 30 percent. Air pollution levels in Rome have dropped 49 percent compared to a year ago. Stars seem more visible at night.
烟雾不再笼罩着新德里，这是全球污染最严重的城市之一。美国东北部的二氧化氮污染下降了30%。罗马的空气污染水平比去年相比下降了49%。星星在晚上也更加耀眼。
People also report seeing wild animals in unusual places. Coyotes have been observed walking in downtown Chicago and near San Francisco's Golden Gate Bridge. A puma was seen in the streets of Santiago, Chile. Goats entered a town in Wales and showed no interest in leaving.
人们还报告称在一些不寻常的地方看到了野生动物。土狼被看到在芝加哥市中心和旧金山金门大桥附近行走。智利圣地亚哥的街道上出现了一只美洲狮。山羊进入了威尔士的一个小镇并且无意离开。
When people stay home, the Earth becomes cleaner and wilder.
当人们呆在家里时，地球变得更加清洁和荒凉。
Cleaner air
空气更清洁
Stuart Pimm is a scientist at Duke University in the United States. He says the stay-at-home orders worldwide are "giving us this quite extraordinary insight into just how much of a mess we humans are making of our beautiful planet."
斯图亚特.皮姆是美国杜克大学的一名科学家。他说，全球范围内的居家令“赋予我们这种非同寻常的洞察力，让我们了解到人类给我们美丽的地球制造了多少混乱。”
Pimm told The Associated Press that the situation is providing a chance to "see how much better it can be."
皮姆在接受美联社采访时表示，这种局面让我们有机会看到地球能有多好。
Scientists, stuck at home like the rest of us, say they are interested in studying unexpected changes in plants, insects, weather, noise and light pollution.
跟我们其他人一样也呆在家里的科学家表示，他们有兴趣研究植物、昆虫、天气、噪声和光污染的意外变化。
Researchers have been observing sharp drops in traditional air pollutants, such as nitrogen dioxide, smog and tiny particles. These kinds of pollutants kill up to 7 million people a year worldwide, says Dan Greenbaum, president of the Health Effects Institute.
研究人员一直在观测传统空气污染物的急剧下降，例如二氧化氮、烟雾和微小颗粒物。健康影响研究所所长丹·格林鲍姆表示，这类污染物每年造成全球高达7百万人死亡。
Cleaner air has been most noticeable in India and China. On April 3, people living in Jalandhar, a city in north India's Punjab, woke up to a sight not seen for many years: snow-covered Himalayan mountains more than 160 kilometers away.
空气更清洁在印度和中国最为显著。4月3日，印度北部旁遮普邦贾朗达尔市的人们一觉醒来，看到了160多公里以外积雪覆盖的喜马拉雅山脉，这是多年未见的景象。
Cleaner air means stronger lungs for asthmatics, especially children, said Mary Prunicki. She is a doctor and director of air pollution and health research at the Stanford University School of Medicine in California. She noted early studies have linked coronavirus severity to people with weak lungs and those living in more polluted areas.
玛丽·普鲁妮基表示，对哮喘患者，尤其是儿童来说，更清洁的空气意味着更强的肺部功能。她是加州斯坦福大学医学院的医生兼空气污染和健康研究主任。她指出，早期研究已经将冠状病毒的严重程度与肺部受损的人们以及生活在污染较严重地区的人们联系起来。
Animals take over
动物接管地球
In Australia, police shared a video of a kangaroo on social media. It showed the animal jumping around a mostly empty neighborhood in downtown Adelaide. Several wild jackals recently occupied a city park in Tel Aviv, Israel.
在澳大利亚，警方在社交媒体上分享了一只袋鼠的视频。视频显示这只袋鼠在阿德莱德市区的一个空旷社区跳来跳去。几只野生胡狼最近占领了以色列特拉维夫的一个城市公园。
We are not being invaded, Duke's Stuart Pimm noted. The wildlife has always been there, but many animals only come out when people are not around.
杜克大学的皮姆指出，我们并未遭到动物入侵。这些野生动物一直在那里，但是许多动物只有在没人的时候才会出来。
Human activity usually makes it difficult for sea turtles to leave their eggs on sandy coastlines. Nesting turtles need to be undisturbed. After they come out of their eggs, baby turtles might have problems finding their way to the water because of bright lights, said David Godfrey. He is executive director of the Sea Turtle Conservancy.
人类活动通常会使海龟很难在沙滩上产卵。筑巢海龟需要保持不受干扰。大卫·戈弗雷表示，当小乌龟从卵中出来后，它们可能会因为灯光明亮很难找到入水的路线。戈弗雷是海龟保护协会的执行理事。
But with lights mostly off and people in their homes, the sea turtle nesting seems much better this year -- from India to Costa Rica to Florida, Godfrey said.
戈弗雷表示，但是由于大部分灯光关闭，人们呆在家里，今年从印度到哥斯达黎加，再到佛罗里达，海龟的筑巢情况似乎要好得多。
"There's some silver lining for wildlife in what otherwise is a fairly catastrophic time for humans," he added.
他还说：“在人类的灾难时刻，野生动物反而看到了一线光明。”
I'm Ashley Thompson.
我是阿什利·汤普森。(51VOA.COM原创翻译，禁止转载，违者必究！)