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UY Scuti

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UY Scuti is a truly giant star located in the Scutum constellation.

New shot of UY Scuti, the former largest known star v2
New shot of UY Scuti, the former largest known star v2

It is known as a red supergiant or a hypergiant. This star is also a pulsating variable star. This means its brightness changes over time. It is too dim to see with just your eyes. It sits about 5,900 light-years away from Earth.

UYSctLightCurve
UYSctLightCurve

This star works by changing its size and light. It is a semiregular variable star. This means it pulses with a period of about 740 days. Inside the star, a special process is happening. It is currently fusing helium in its center. It also fuses hydrogen in a shell around that core. Eventually, the star will make iron in its core. This will cause the star to collapse and explode.

UY Scuti zoomed in, DSS2 survey, 2003
UY Scuti zoomed in, DSS2 survey, 2003

People first found this star in 1860. German astronomers at the Bonn Observatory cataloged it. They were working on the Bonner Durchmusterung Stellar Catalogue. They gave it the name BD-12°5055. This name shows its place in their star survey. Later, it was named UY Scuti. This name means it was the 38th variable star in Scutum.

Scientists use many numbers to describe this huge star. Some estimates say its volume is 750 million times the Sun. If placed in our solar system, it would reach past Mars. In 2012, the Very Large Telescope in Chile studied it. Scientists found it was much more luminous than the Sun. A 2023 measurement put its radius at 1,700 times the Sun. Its temperature is about 3,550K.

UYSctLightCurve
UYSctLightCurve

It is helpful to think about how big this star is. Imagine our Sun as a tiny marble. UY Scuti would be like a giant building next to it. It is also very dusty and loses mass every year. This creates a big cloud of gas and dust around it. It sits deep in the Milky Way disc. This makes it a metal-rich star. Even though it is huge, it is hard to see clearly. It sits in a place called the Zone of Avoidance.

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🖼️ Images & Media (3)
File:UY Scuti zoomed in, DSS2 survey, 2003.png
UY Scuti zoomed in, DSS2 survey, 2003.png
File:UYSctLightCurve.png
UYSctLightCurve.png
File:New shot of UY Scuti, the former largest known star v2.png
New shot of UY Scuti, the former largest...
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