A Summer of Super Moons presented by Science@NASA

暑假的超大月亮，由美國太空總署所發表

In June of last year, a full Moon made headlines.

去年7月，一個登上頭條的滿月。

The news media called it a "supermoon" because it was 14% bigger and 30% brighter than other full Moons of 2013.

媒體稱它為"超級月亮"因為它比2013年其它的滿月還要大上14%且亮度也多了30%。

Around the world, people went outside to marvel at its luminosity.

世界各地，人們到外頭來目睹它的"光"彩。

If you thought one supermoon was bright, how about three....?

如果你認為一個超級月亮很明亮，那三個呢....?

The full Moons of summer 2014, July 12th, August 10th and Sept 9th will all be supermoons.

2014暑假的滿月落在 7/12,8/10和 9/9--且都將會是超級月亮。

The scientific term for the phenomenon is 'perigee moon.'

對於此現象的科學術語為"近地月"。

Full Moons vary in size because of the oval shape of the Moon's orbit.

滿月因大小而異由於月亮的運行軌跡呈橢圓狀。

The Moon follows an elliptical path around Earth with one side ('perigee') about 50,000 km closer than the other ('apogee').

而月亮以橢圓的路徑繞著地球轉（近地點）的那側離另一側（遠地點）約50,000公里。

Full Moons that occur on the perigee side of the Moon's orbit seem extra big and bright.

滿月發生在月球軌跡的近地點似乎格外的大也更加的亮。

This coincidence happens three times in 2014.

此現象在2014發生三次為巧合。

On July 12th and Sept 9th, the Moon becomes full on the same day as perigee.

在7/12與9/9號，月球在近地點時也剛好是滿月。

On August 10th it becomes full during the same hour as perigee arguably making it an extra-super Moon.

在8/10時，也在近地點的同時滿月也就是說使它成為超大月亮。

It might seem that such a sequence must be rare.

這樣的日期次序似乎極為稀少。

Not so, says Geoff Chester of the US Naval Observatory.

美國海軍天文台人員 Geoff Chester 不這麼認為。

“Generally speaking, full Moons occur near perigee every 13 months and 18 days, so it's not all that unusual,” he says.

“大體上，每13個月又18天 滿月會在近地點旁發生，所以並非所有都那麼不尋常,”他說。

“In fact, just last year there were three perigee Moons in a row, but only one was widely reported.”

事實上，光是去年就連續發生3次近地月，但只有一次被廣泛的報導。

In practice, it's not always easy to tell the difference between a supermoon and an ordinary full Moon.

事實上，不是總能輕鬆分辨超級月亮與普通的滿月。

A 30% difference in brightness can easily be masked by clouds and haze.

亮度上30%的差異卻很容易被雲層和薄霧所遮蔽。

Also, there are no rulers floating in the sky to measure lunar diameters.

再者，目前也無法將尺懸浮到天空來測量月亮的直徑。

Hanging high overhead with no reference points to provide a sense of scale, one full Moon looks about the same size as any other.

月亮高掛頭頂而沒有對照點來衡量比例，其中一滿月看起來跟其它的約略同大小。

Chester expects most reports of giant Moons this summer to be ...

Chester 預期對於這個暑假超大月亮的報導多屬...

illusory.

幻覺的

''The Moon Illusion is probably what will make people remember this coming set of Full Moons, more than the actual view of the Moon itself,” he says.

"月亮幻覺可能讓人記住眼前的月色，多於實際的景像,”他說。

The illusion occurs when the Moon is near the horizon.

當月亮接近地平線時,此幻覺就會發生

For reasons not fully understood by astronomers or psychologists, low-hanging Moons look unnaturally large when they beam through trees, buildings and other foreground objects.

因為天文學家和心理學者還無法充分了解低懸月的光穿越樹林, 建築物與其他最前景的物體時, 看起來大的不自然。

When the Moon illusion amplifies a perigee Moon, the swollen orb rising in the east at sunset can seem super indeed.

當月幻覺使近地月變大時，這腫脹的球體會在黄昏時從東邊升起且的確很大。

"I guarantee that some folks will think it's the biggest Moon they've ever seen if they catch it rising over a distant horizon, because the media will have told them to pay attention to this particular one," says Chester.

"我敢保證有些人會認為這是他們看過最大的月亮，假如他們能抓住高於地平線的它，因為媒體會跟他們說要注意特別的這個," Chester說。

"There's a part of me that wishes that this 'super-Moon' moniker would just dry up and blow away, like the term 'Blood-Moon' that accompanied the most recent lunar eclipse, because it tends to promulgate a lot of mis-information," admits Chester.

我也有一些心願就是 "超級月亮" 的稱號能日漸被淡忘,隨風而逝，就像 "血月亮" 這個說詞是伴隨著最近的月蝕而誕生的，因為這樣總會傳達許多錯誤資訊，Chester 坦承。

"However, if it gets people out and looking at the night sky and maybe hooks them into astronomy, then it's a good thing."

然而，如果這樣能使大家出門一觀其夜色或也許使他們著迷天文學，這也是好事。

Indeed it is.

確實如此。

Mark your calendar July 12th, August 10th, and Sept 9th and enjoy the super-moonlight !

在你的月曆標上 7/12, 8/10, 9/9 然後等著享受超亮月光吧！

For more news about big bright things in the night sky, visit science. nasa. gov.

想得知更多資訊有關夜空裡又大又亮的東西，來 science.hasa.gov。