Betelgeuse
Orion's red shoulder — a dying supergiant.
Betelgeuse is so big that, in the Sun's place, it would swallow Mars. It is near the end of its life and will one day explode as a supernova — possibly bright enough to see in daylight. "One day" could mean any time in the next 100,000 years.
Did you know?
In 2019–2020 it dimmed noticeably after puffing out a cloud of dust.