The final, dying outbursts of an unstable star are captured by Hubble

By Georgina Torbet September 19, 2021

Earlier this year, Hubble celebrated its 31st anniversary with a release of an image of the unstable star AG Carinae. Now, Hubble researchers have returned to this star to show it from two different views, complied from observations in 2020, 2014, and 1994.

This view of AG Carinae showcases the details of the ionised hydrogen and ionised nitrogen emissions from the nebula (seen here in red). — This view of AG Carinae showcases the details of the ionized hydrogen and ionized nitrogen emissions from the nebula (seen here in red). ESA/Hubble and NASA, A. Nota, C. Britt

The first view of the star shows the ionized hydrogen and nitrogen which it emits, and which form a shell around the hot core. This shell is expanding over time as gases are thrown off.

In this image of AG Carinae, the blue demonstrates the contrasting appearance of the distribution of the dust that shines of reflected stellar light. — In this image of AG Carinae, the blue demonstrates the contrasting appearance of the distribution of the dust that shines of reflected stellar light. ESA/Hubble and NASA, A. Nota, C. Britt

The second view of the star shows how dust is distributed around the star, which is represented in blue. This dust shines brightly because it reflects the light given off by the star, and it is shaped by stellar winds which are coming from the star as well.

The star’s dramatic appearance is because it is very massive and coming to the end of its life. As it ages and uses up all of its fuel, the star becomes unstable and throws off both dust and gases.

“AG Carinae is formally classified as a Luminous Blue Variable because it is a hot (emitting blue light), brilliant star that varies in brightness,” the Hubble scientists explain. “Such stars are quite rare because few are so massive. Luminous Blue Variable stars continuously lose mass in the final stages of life. The star is waging a tug-of-war between gravity and radiation pressure to avoid self-destruction. As the star begins to run out of fuel, its radiation pressure decreases, and gravity begins to take hold. Stellar material succumbs to gravity and falls inward. It heats up and is explosively ejected into the surrounding interstellar space. This process continues until enough mass is lost and the star reaches a stable state.”

Gases are being thrown off the star at a tremendous speed of 43 miles per second, and its beautiful shell is formed from previous ejections. The shell of material that forms the nebula is around 10,000 years old and is approximately five light-years across.

Editors' Recommendations

Topics

Georgina Torbet

Space Writer

Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…

Space

Hubble celebrates its 33rd birthday with stunning nebula image

Astronomers are celebrating the NASA/ESA Hubble Space Telescope’s 33rd launch anniversary with an ethereal photo of a nearby star-forming region, NGC 1333. The nebula is in the Perseus molecular cloud, and is located approximately 960 light-years away.

It will soon be the 33rd anniversary of the launch of the Hubble Space Telescope, and to celebrate this milestone, Hubble scientists have shared a stunning image taken by the telescope of a picturesque nebula. NGC 1333 is a busy stellar nursery, with new stars forming among the cloud of dust and gas located 960 light-years away.

The beautiful image of the nebula shows swirls of dark dust around glowing points of light where new stars are being born. To capture this scene, Hubble used its instruments across their full wavelengths, from ultraviolet through the optical light range and into the near-infrared. Hubble took the image using its Wide Field Camera 3 instrument, which used several filter across different wavelengths that were then assigned to colors (Blue: F475W, Green: F606W, Red: F657N and F814W) to create the colorful final result.

Space

Unique black hole is trailed by 200,000 light-year-long tail of stars

This is an artist's impression of a runaway supermassive black hole that was ejected from its host galaxy as a result of a tussle between it and two other black holes. As the black hole plows through intergalactic space it compresses tenuous gas in front to it. This precipitates the birth of hot blue stars. This illustration is based on Hubble Space Telescope observations of a 200,000-light-year-long contrail of stars behind an escaping black hole.

Black holes might have a reputation as terrifying monsters, devouring all they come into contact with -- but they can be a force of creation too, feeding the formation of new stars. Researchers using data from the Hubble Space Telescope recently spotted an unexpectedly huge trail of stars forming in the wake of a rogue black hole.

While most very large black holes, called supermassive black holes, sit at the center of galaxies, occasionally these enormous beasts can be found wandering alone in the depths of space. That's the case with the recently discovered black hole with the mass of 20 million suns, which is streaking through the sky at tremendous speed. This likely began with two galaxies merging, each with its own supermassive black hole, which formed a binary system. Then a third galaxy got too close, and in the chaos of a three-way merger one of the black holes was kicked out and sent zipping off into space -- so fast that if it were in our solar system, it would travel from the Earth to the moon in 14 minutes.

Space

James Webb captures the rarely-seen rings around Uranus

This zoomed-in image of Uranus, captured by Webb’s Near-Infrared Camera (NIRCam) on 6 February 2023, reveals stunning views of the planet’s rings. The planet displays a blue hue in this representative-colour image, made by combining data from two filters (F140M, F300M) at 1.4 and 3.0 microns, shown here as blue and orange, respectively.

The James Webb Space Telescope spends much of its time peering out into distant regions of space searching for some of the earliest galaxies to exist, but it also occasionally turns its sights onto targets a little closer to home. Following up on its image of Neptune released last year, astronomers using Webb have just released a brand-new image of Uranus as you've never seen it before.

As Webb looks in the infrared wavelength, unlike telescopes like Hubble which look in the visible light spectrum, its image of Uranus picks out some features of the planet which are hard to see otherwise like its dusty rings. Uranus' rings are almost invisible in the optical wavelength, but in this new image, they stand out proudly.