Merak is a white star at the bottom of the bowl of the Plough, one of the two Pointers that lead the eye from the Great Bear to Polaris.
At a glance
| type | white star (class A) |
|---|---|
| distance from the Sun | 79.7 light-years (24.4 pc) |
| its light left it | 79.7 years ago |
| luminosity | 72.3 × the Sun |
| radius | 3.28 × the Sun |
| surface temperature | 9,300 K |
| constellation | Ursa Major (Great Bear) |
Read off the piece’s own catalogue, the same values it draws with.
About Merak
The facts describe a hot white star, larger and more luminous than the Sun. Its infrared glow shows that it is surrounded by a disc of cold dust, the kind of debris that colliding bodies leave around a star.
Draw a line from Merak through Dubhe and continue it, and it reaches Polaris, the Pole Star: that is why the two are called the Pointers. The name comes from the Arabic for the loins or flank of the bear.
Merak belongs to the Ursa Major moving group, a loose family of stars born together that still travel through space in the same direction. Most of the Plough’s stars are members; Dubhe and Alkaid are not.
What you see in the piece
In the piece Merak is drawn at its true distance and brightness. Fly out and the Plough comes apart, though its middle stars, moving together, stay closer to one another than Dubhe and Alkaid do.
Questions
Why is Merak called a Pointer?
A line from Merak through Dubhe, extended across the sky, leads to Polaris, the Pole Star.
How far away is Merak?
Merak is 79.7 light-years (24.4 pc) from the Sun; its light left it 79.7 years ago.