• Eta Carinae, a star system 7,500 light-years away, is about to undergo a cataclysmic explosion.
• The primary star in the system is 90 times the mass of the sun and outshines it by 5 million times.
• Eta Carinae experienced a massive outburst in the 1840s, becoming the second-brightest star in the night sky.
• NASA's Hubble Space Telescope and other observatories have provided valuable data on Eta Carinae's structure and behavior.