Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2016 August 8
See Explanation.
Moving the cursor over the image will bring up an annotated version.
Clicking on the image will bring up the highest resolution version

Perseid Meteors over Mount Shasta
Image Credit & Copyright: Brad Goldpaint (Goldpaint Photography)

Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks later this week is known as the Perseids -- the meteors all appear to came from a radiant toward Perseus. In terms of parent body, though, the sand-sized debris that makes up the Perseids meteors come from Comet Swift-Tuttle. The comet follows a well-defined orbit around our Sun, and the part of the orbit that approaches Earth is superposed in front of the Perseus. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in Perseus. Featured here, a composite image containing over 60 meteors from last August's Perseids meteor shower shows many bright meteors that streaked over Mount Shasta, California, USA. This year's Perseids holds promise to be the best meteor shower of the year.

Transparent Science: Browse 1,300+ codes in the Astrophysics Source Code Library
Tomorrow's picture: passing mars

< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
NASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC
& Michigan Tech. U.