约书亚树国家公园上空的银河，美国加利福尼亚州 Milky Way over Joshua Tree National Park, California (© Schroptschop/Getty Images)

约书亚树国家公园上空的银河，美国加利福尼亚州 Milky Way over Joshua Tree National Park, California (© Schroptschop/Getty Images)

沙漠上空的星海 An ocean of stars above the desert

国际天文

今天是天文日，快准备好望远镜和星图APP去观星吧！为了让更多人对太空感兴趣，道格·伯杰于1973年创立了天文日，他在街角、商场和公园里架设了望远镜，让人们有机会亲眼看到星星。

早期的天文学家缺乏工具，只能凭肉眼观测天体，但他们仍然取得了重大的成就，例如计算月球的大小和距离，确认太阳是太阳系的中心，以及预测恒星运动和地球季节的关系。如今，我们拥有各种先进的望远镜，有詹姆斯韦伯太空望远镜，也有便携式望远镜，在国际黑暗天空公园里你都能看到有人在用这些先进的设备观星。

Astronomy Day

Get your telescope and star map app ready because it's Astronomy Day! Doug Berger, then president of the Astronomical Association of Northern California, created Astronomy Day in 1973 to get more people interested in the wonders of space. He set up telescopes on street corners, malls, and parks to give people a chance to see the stars firsthand.

Early astronomers lacked the means to view celestial objects beyond those which could be seen by the naked eye. But they still made major discoveries, such as calculating the size and distance of the moon, affirming the sun as the center of our solar system, and predicting the movement of stars relative to the seasons. Today we have sophisticated telescopes, from the orbiting James Webb Space Telescope to the portable ones you'll find in use at International Dark Sky Parks, including Joshua Tree National Park, seen in our photo. With such ground-breaking technology at our disposal, astronomers can boldly go where no human eyes have gone before.