The Hubble Space Telescope has gotten into the Halloween spirit, capturing an image of the carbon star CW Leonis, resembling a glowering orange-hued eye.
The star lies around 400 light-years from Earth in the constellation Leo and is a carbo-rich red star surrounded by clouds of sooty gas and dust. These envelopes were created when the dying star's core collapsed, blowing out its outer layers.
This process happens to all stars of the size of CW Leonis when they run out of hydrogen to burn in their cores. This means that nuclear fusion is stopped, and the outward pressure that supports a star from the effects of gravity ceases.
This triggers a gravitational collapse that triggers the burning of helium in the star's core. This heats the outer layers puffing them out in what is known as the red giant phase.
This will happen to the sun in about 4 billion years, and our star will expand out to the orbit of Mars, in the process engulfing the inner planets, including Earth.
For CW Leonis, this process has left the stellar core surrounded by sooty dust that makes it appear to Hubble as a single glowing eye.
Aside from admiring its haunting aesthetic, studying CW Leonis with Hubble is helping researchers understand the interaction between dying stars and their outer layers.
It isn't just old stars that are capable of putting on a cosmic horror show, however.
This image shows the billowing clouds of gas and dust that make up a nebula where baby stars are brewing, lit up by massive stars hundreds of light-years from Earth.
The nebula, located in the constellation of Orion, is glowing in infrared light which gives it the distinct appearance of a typical "wicked witch" as depicted in lurid Halloween decorations, screaming out into space.
It's little wonder that the cloud of gas and dust has been named the Witch Head Nebula. Its image here was caught by the Wide-field Infrared Survey Explorer (WISE) in 2017.
Another young star, HBC 672, has received the nickname Bat Shadow because of its similarity to the image of Earth's only winged mammal and Halloween staple.
The similarity between HBC 672 and a bat was taken even further in 2018, when Hubble spotted a curious "flapping" motion in the star's shadow caused by motion in the planet-forming disc of gas and dust that surrounds it.
This is likely caused by a planet in the disc orbiting that central star and pulling on the gas and dust warping it.
"You have a star that is surrounded by a disc, and the disc is not like Saturn's rings—it's not flat. It's puffed up," said Klaus Pontoppidan, an astronomer at the Space Telescope Science Institute (STScI) in Baltimore, who helped discover the "flapping" motion. "And so that means that the light from the star, if it goes straight up, can continue straight up—it's not blocked by anything. But if it tries to go along the plane of the disc, it doesn't get out, and it casts a shadow."
If this star's bat-like appearance isn't intimidating enough, the shadow that surrounds it is truly massive. The fact that the shadow is 200 times the size of the solar system means that it takes light 45 days to cross it.
The star is in the Sharpens nebula, around 1,300 light-years away from Earth. This image was captured in 2018.
Halloween wouldn't be complete with a pumpkin.
This Hubble Space Telescope image shows aging red stars in the galaxies NGC 2292 and NGC 2293 in the constellation Canis Major resembling two glowing eyes and a rictus grin.
And this cosmic pumpkin is a whopper, measuring 109,000 light-years across. The two galaxies are actually in the process of colliding. This collision is creating spiral arms, the first of which is forming this haunting grin.
