Antares, 15th brightest star in the sky and about 170 light years away, is the brightest star in the constellation of Scorpius and one of the biggest stars known, a supergiant with a diameter 400 times that of the Sun.
It fluctuates in brightness over an approximately five-year cycle and has a much smaller bluer companion orbiting it over 900 years. On the left is a comparison of the Sun (arrowed in the image) with Antares. The star Arcturus is also shown for comparison as is the size of Mars’ orbit (dotted line).
In the photo to the right Antares is the brightest star, to the lower left. The guide below shows some of the other principal stars in the photo, and below that you can see a constellation map of Scorpius, on a much smaller scale, which shows that Scorpius is indeed one of the constellations that does look like its traditional image. Once it included the stars of Libra which formed its claws, making the resemblance even stronger.