今晚新年夜 月亮变蓝色!？

欢迎您访问52ij英汉互译网，今天小编为你分享的英语知识是：【今晚新年夜 月亮变蓝色!？】，下面是详细的分享！

今晚新年夜 月亮变蓝色!？

"Blue Moon" to Shine on New Year's Eve

For the first time in almost 20 years, a bright "blue moon" will grace New Year's Eve celebrations worldwide.

If the skies are clear, revelers looking up at midnight will get an eyeful of the second full moon of the month—commonly called a blue moon. The last time a blue moon appeared on New Year's Eve was in 1990, and it won't happen again until 2028.

A blue moon isn't actually blue—as commonly defined, the name reflects the relative rarity of two full moons in a month and is linked to the saying "once in a blue moon."（52ij英汉互译小编注：once in a blue moon,英语俗语，意思是极少的、破天荒的。）

With this New Year's Eve blue moon, "there is nothing scientific about it, and it has no astronomical significance," said Mark Hammergren, a staff astronomer at the Adler Planetarium in Chicago, Illinois.

"But I believe it does give us some insight into history and makes us think of how our calendar system has derived from motions of objects in the sky."

Blue Moon Error

The popular definition of a blue moon isn't the only one—and it's one that's based on an editorial error, astronomers contend.

The widespread definition of the second full moon in a month stems from errors made in an astronomy magazine, when a writer misinterpreted how the term was used in the Maine Farmer's Almanac.

Later studies of almanacs published from 1819 to 1962 revealed that the term "blue moon" actually refers to the "extra" full moon that can occur in a year due to differences between the calendar year and the astronomical year.

Most years on average have 12 full moons, with 1 appearing each month.

That's because the lunar month—the time it takes the moon to cycle through its phases—corresponds closely to the calendar month.

But the calendar year is actually based on the solar cycle, or the time it takes Earth to make one trip around the sun. This means a year is not evenly divisible by lunar months, so every three years or so there are 13 full moons.

The farmer's almanac further divided the year into four seasons, with each season lasting three months. When a given season saw four full moons, the almanac dubbed the third moon as a blue moon.

Ultimately, a blue moon as defined by the calendar isn't that rare, added Hammergren. The term's significance instead lies in the way it links people to the motions of the cosmos.

"Just being able to recognize that we can have a full moon twice in a month and have [folklore] attached really highlights the fact that humans have been astronomers their entire existence," he said.

"True" Blue Moon

Before the editorial error, the term "blue moon" more often referred to the rare instances when the moon actually seemed to turn blue, as can happen under certain atmospheric conditions.

"After a forest fire or volcanic eruption, there may be enough particulate matter in the air so that the moon can take on a bluish tinge," Hammergren said.

For instance, a "true" blue moon occurred in 1950 after a large forest fire in Canada blew smoke across most of the Northern Hemisphere.

Another appeared in 1980 after the last major eruption of Mount St. Helens, which sent tons of ash into the upper atmosphere.

Although rumblings at the Mayon Volcano in the Philippines seem to signal a major eruption is imminent, experts don't think Mayon's current output will make this New Year's Eve full moon turn blue.

Howling at the Blue Moon

Even if the 2009 New Year's Eve blue moon has astronomers scoffing, nighttime partygoers may still get moonstruck.

Rising in the east at sunset, the New Year's Eve full moon will reach its highest point at midnight, noted Jack Horkheimer, director of the Miami Space-Transit Planetarium and host of PBS television's long-running show Star Gazer.

"Full moons around winter solstice rise their highest for the entire year," Horkheimer added.

"Even if you are downtown in a large city, if it is clear at the stroke of midnight the moon will be very visible if you look up."

In any location, the high, silvery orb will seem like a floodlight cast on the landscape, added Horkheimer, who is organizing a national moon-howling contest around this year's blue moon.

"This is especially true where the ground is covered with a blanket of snow. There is nothing quite so spectacular as a snow-covered scene under a December full moon at midnight."

相关中文阅读：南北美州和欧洲天空将出现美丽浪漫"蓝月亮" （转自搜狐科学频道）

据国外媒体报道，2010年的新年夜在南北美洲和欧洲天空将会出现“蓝月亮”。天文学家表示，“蓝月亮”与月亮的颜色没有多大关系，只是在部分地区由于环境的改变而能看到蓝色的月亮。

据报道，南北美洲和欧洲等地在12月2日已经出现过一次满月，但在2010年的新年夜满月将再次出现在苍穹。在天文历法中，当一个月出现两次满月时，第二个满月就被赋予一个充满神秘浪漫色彩的名字——“蓝月亮” （blue moon）。

天文学家称，美国、加拿大、欧洲、南美洲和非洲等地的新年夜将可以看到“蓝月亮”。而对澳大利亚和亚洲的人们来说，要到元旦那天才能看到满月，这些地方在明年一月会出现“蓝月亮”。同时，东半球的人们在新年夜可以观测到月偏食，而美国将看不到这次月偏食。

根据历法计算，满月每隔29.5天出现一次，而目前采用的公历历法中每个月的时间大月为31天，小月为30天，这就出现了一个时间差，导致一个月可能同时出现两个满月。平均来说，每两年半出现一次“蓝月亮”，上次出现“ 蓝月亮”的时间为2007年5月。在新年夜出现“蓝月亮”的几率非常少，每隔19年出现一次。上一次新年夜“蓝月亮”发生在1990年，下一次出现的日期至少要到2028年。

然而，加利福尼亚大学的天文学家格雷格·劳克林（Greg Laughlin）称“蓝月亮”没有实际的天文意义。劳克林在一封邮件中说：“蓝月亮没有实际的天文意义，就像中秋后的第一个满月“狩猎月”那样，仅仅是一个名字而已。”

据报道，1946年《天空和望远镜》的一位作者误解了缅因州农民的历书，将一个月中的第二个满月称为“蓝月亮 ”。实际上，当一个季度中出现4次满月时，第3个满月才被称作蓝月亮。虽然数十年后《天空和望远镜》的作者对这个错误进行了更正，但是关于“蓝月亮”的定义已经流行开来。因此，对那些“纯粹主义者”来说，新年夜的满月不能被称 作“蓝月亮”，只算是冬季的第一个满月。