The evening star will be travelling through Gemini this week to line up with Castor and Pollux
This whole week, Venus shines in the western evening sky. It will be easy to see why the classical Greeks called it Hesperus or evening star. The reason is that it is so bright. It is travelling through the constellation Gemini, the twins, and by the weekend, it will line up with the stars Castor and Pollux. These are the brightest stars in the constellation and are named after twin brothers in both Greek and Roman mythology. Venus appears so consistently bright for two reasons. Firstly, it is an inferior planet to Earth, meaning that its orbit is closer to the sun. At just three quarters of the Earth’s orbital radius, it receives more light than the Earth. Secondly, it bounces this light back into space because it is permanently covered in reflective clouds. On Earth we get to enjoy it as a brilliant beacon in the twilight sky. Look for it low in the west between 21:00 and 23:00 BST.