24/04/2021
Happy Birthday Hubble.
In celebration of the 31st anniversary of the launching of the NASA/ESA Hubble Space Telescope, astronomers aimed the celebrated observatory at one of the brightest stars seen in our galaxy to capture its beauty.
The giant star featured in this latest anniversary image is waging a tug-of-war between gravity and radiation to avoid self-destruction. The star, called AG Carinae, is surrounded by an expanding shell of gas and dust — a nebula — that is shaped by the powerful winds of the star. The nebula is about five light-years wide, which equals the distance from here to our nearest star, Alpha Centauri.
Learn more about the anniversary image: http://orlo.uk/V06Tz
Here are some cool facts about stars like the one imaged here, called Luminous Blue Variable (LBV)
🌟These stars are among the most massive and brightest stars known.
🌟They live for only a few million years, compared to the roughly 10-billion-year lifetime of our own Sun.
🌟They have a dual personality. They appear to spend years in semi-quiescent bliss and then they erupt in a petulant outburst, during which their luminosity increases.
🌟Major outbursts such as the one that produced the nebula featured in this image occur a few times during a LBV’s lifetime.
🌟A LBV star only casts off material when it is in danger of self-destruction.
🌟They are in a constant battle to maintain stability. It’s an arm-wrestling contest between radiation pressure from within the star pushing outward and gravity pressing inward.
🌟LBV stars are rare: fewer than 50 are known among the galaxies in our local group of neighbouring galaxies.
🌟Some are expected to end their lives in titanic supernova blasts, which enrich the Universe with the heavier elements beyond iron.
Image credit: NASA - National Aeronautics and Space Administration / ESA - European Space Agency and Space Telescope Science Institute
