Astronomers studying a famous supernova located 168,000 light-years from Earth have made new observations inside the structure that may help unlock the mysteries of exploding stars.

The supernova, known as SN 1987A and first discovered in 1987, has been studied by scientists for decades. A supernova is the powerful explosion of a star, which occurs when a star has reached the end of its lifespan. 

The recent observations revealed a central structure, shaped like a keyhole, "packed with clumpy gas and dust ejected by the supernova explosion," according to NASA. Researchers said the dust is so dense that even the highly advanced James Webb Space Telescope cannot see through it, causing the "hole" shape in the keyhole structure. 

The shape is also formed by a bright surrounding ring and two hourglass-shaped outer rings. The surrounding, equatorial ring is made up of material ejected millennia before the supernova exploded. The ring also has bright hot spots, formed by the supernova's shock wave hitting it. 

These structures have been observed in the past with technology like NASA's Hubble Space Telescope and Spitzer Space Telescope. But "the unparalleled sensitivity and spatial resolution of Webb revealed a new feature in this supernova remnant – small crescent-like structures"  that astronomers believe to be part of the "outer layers of gas shot out" by the explosion. The crescent shapes are bright, which may be "limb brightening," which NASA described as an optical phenomenon caused by "viewing the expanding material in three dimensions."  

The supernova will continue to be observed by the Webb telescope. Instruments on the telescope will continue to allow astronomers to capture new data and learn more about the crescent structures. 

The new observations "provide a crucial clue to our understanding of how a supernova develops over time to shape its remnant," NASA said.

The James Webb Space Telescope is the "world's premier space science observatory," according to NASA, and works with other observatories to study space. The telescope is an international program led by NASA, the European Space Agency and the Canadian Space Agency. 

In:
• James Webb Space Telescope
• Space
• NASA

Kerry Breen

Kerry Breen is a news editor and reporter for CBS News. Her reporting focuses on current events, breaking news and substance use.