Does the moon look smaller tonight? Here's why a 'micromoon' rises

今晚的月亮看起来更小了吗？原因是"微月"正在升起

If you're an avid moon-watcher, you might notice that our moon appears just a tiny bit smaller in the night sky tonight.

如果你是个热衷赏月的人，或许会注意到今晚夜空中的月亮看起来稍微小了一点。

On Monday (Feb. 17), the moon reaches what's known as apogee  — its farthest point away from Earth. The moon's orbit is elliptical, or oval-shaped, meaning its distance from Earth changes throughout its 27.3-day cycle around our planet. Sometimes it's closer to us, which is why we experience "supermoons," or full moons that appear slightly larger in the night sky.

周一（2月17日），月球将到达"远地点"——即其绕地轨道上距离地球最远的位置。由于月球轨道呈椭圆形，所以在它为期27.3天的公转周期中，与地球的距离会不断变化。当月球离我们更近时，我们会看到"超级月亮"，抑或是看起来略大的满月悬挂夜空。

But at other times, like tonight, the moon is farther away, making it appear smaller. The moon's distance only changes by around 14% as it moves closer to and farther away from Earth during its orbit though, so for most skywatchers, the change in size won't be visibly apparent.

但在其他时候，比如今晚，月球会运行到距离地球较远的位置，使其看起来更小。不过由于月球在轨道上远近变化时，与地球的距离只会变化14%左右，因此大多数观星者很难察觉这种大小变化。

The exact moment of apogee occurs at 8:10 p.m. ET (0110 GMT on Feb. 18) tonight, but the moon will be below the horizon at the time. For observers in the Northern Hemisphere, the moon won't rise above the eastern horizon until shortly before midnight, still at the farther end of its orbit from Earth. The moon will be in the Virgo constellation.

今晚月球到达远地点的精确时间为美国东部时间今晚8：10（格林威治时间2月18日13:10），但那时月球仍处地平线以下。对于北半球的观测者来说，月球要到午夜前才会从东方地平线升起，且仍处于轨道上离地球更远的的位置。届时月亮将在处女座。

Tonight's moon is 19 days old (past new moon), in the waning gibbous phase, and approaching its next phase, the half-lit third quarter moon, which occurs on Feb. 20. Despite the moon being half-illuminated, we call this the "third quarter phase" because it comes when the moon is three-quarters of the way through its orbit around Earth.

今晚的月亮已过新月期19天，正处于渐亏的凸月阶段，并即将在2月20日进入下一个阶段，半亮的弦月阶段。尽管此时月球仅有一半被照亮，但我们仍称之为"下弦月阶段"，因为它标志着月球已完成绕地轨道的四分之三。

After third quarter, the next phase in the moon's cycle will be the new moon on Feb. 27. One day later, the moon will be just a one-day-old sliver, appearing between Saturn and Mercury in the night sky.

下弦月之后，月球将在2月27日迎来下一个新月阶段。一天后，月龄仅一天的纤细月牙将现身夜空，位于土星和水星之间。

Want to see craters and other features on the moon? Our guides to the best telescopes and best binoculars are helpful tools for anyone hoping to get a closer look at Earth's natural satellite.

想要观测月球上的陨石坑和其他特征吗？我们的《最佳望远镜指南》和《最佳双筒望远镜推荐》能为任何想要近距离观察这颗地球天然卫星的爱好者提供帮助。

And if you're looking to take photos of the night sky or the moon, check out our guides on how to photograph the moon, how to shoot the night sky, and our guides to the best cameras for astrophotography and best lenses for astrophotography.

如果你想拍摄夜空或月亮，可以参考我们的指南：《如何拍摄月亮》《如何拍摄夜空》，以及我们的《最佳天文摄影相机推荐》和《最佳天文摄影镜头推荐》。

Editor's Note: If you get a good photo of the moon, and would like to share it with Space.com's readers, send your photo(s), comments, and your name and location to spacephotos@space.com.

编者提示：如果您拍摄到了精彩的月球照片，并想与Space.com的读者分享，请将您的照片、拍摄心得、姓名及拍摄地点发送至spacephotos@space.com。