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In celebration of the 34th anniversary of the launch of the legendary NASA/ESA Hubble Space Telescope, astronomers took a snapshot of the Little Dumbbell Nebula (also known as Messier 76, M76, or NGC 650/651) located 3400 light-years away in the northern circumpolar constellation Perseus. The photogenic nebula is a favourite target of amateur astronomers.

M76 is classified as a planetary nebula. This is a misnomer because it is unrelated to planets. But its round shape suggested it was a planet to astronomers who first viewed it through low-power telescopes. In reality, a planetary nebula is an expanding shell of glowing gases that were ejected from a dying red giant star. The star eventually collapses to an ultra-dense, hot white dwarf.

M76 is composed of a ring, seen edge-on as the central bar structure, and two lobes on either opening of the ring. Before the star burned out, it ejected the ring of gas and dust. The ring was probably sculpted by the effects of the star that once had a binary companion star. This sloughed-off material created a thick disc of dust and gas along the plane of the companion’s orbit. The hypothetical companion star isn’t seen in the Hubble image, and so it could have been later swallowed by the central star. The disc would be forensic evidence for that stellar cannibalism.

The primary star is collapsing to form a white dwarf. It is one of the hottest stellar remnants known at a scorching 120 000 degrees Celsius, 24 times our Sun’s surface temperature. The sizzling white dwarf can be seen as a pinpoint in the centre of the nebula. A star visible in projection beneath it is not part of the nebula.

Pinched off by the disc, two lobes of hot gas are escaping from the top and bottom of the ‘belt’ along the star’s rotation axis that is perpendicular to the disc. They are being propelled by the hurricane-like outflow of material from the dying star, tearing across space at two million miles per hour. That’s fast enough to travel from Earth to the Moon in a little over seven minutes! This torrential ‘stellar wind’ is ploughing into cooler, slower-moving gas that was ejected at an earlier stage in the star’s life, when it was a red giant. Ferocious ultraviolet radiation from the super-hot star is causing the gases to glow. The red colour is from nitrogen, and blue is from oxygen.

The entire nebula is a flash in the pan by cosmological timekeeping. It will vanish in about 15 000 years.

[Image description: A Hubble image of the Little Dumbbell Nebula. The name comes from its shape, which is a two-lobed structure of colourful, mottled glowing gases that resemble a balloon that has been pinched around a middle waist. Like an inflating balloon, the lobes are expanding into space from a dying star seen as a white dot in the centre. Blistering ultraviolet radiation from the super-hot star is causing the gases to glow. The red colour is from nitrogen, and blue is from oxygen.]


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This NASA/ESA Hubble Space Telescope image of the barred spiral galaxy UGC 12158 looks like someone took a white marking pen to it. In reality it is a combination of time exposures of a foreground asteroid moving through Hubble’s field of view, photobombing the observation of the galaxy. Several exposures of the galaxy were taken, which is evidenced by the dashed pattern.

The asteroid appears as a curved trail as a result of parallax: Hubble is not stationary, but orbiting Earth, and this gives the illusion that the faint asteroid is swimming along a curved trajectory. The uncharted asteroid is inside the asteroid belt in our Solar System, and hence is 10 trillion times closer to Hubble than the background galaxy.

Rather than being a nuisance, this type of data is useful to astronomers for doing a census of the asteroid population in our Solar System.

[Image description: This is a Hubble Space Telescope image of the barred spiral galaxy UGC 12158. The majestic galaxy has a pinwheel shape made up of bright blue stars wound around a yellow-white hub of central stars. The hub has a slash of stars across it, called a bar. The galaxy is tilted face-on to our view from Earth. A slightly S-shaped white line across the top is the Hubble image of an asteroid streaking across Hubble’s view. It looks dashed because the image is a combination of several exposures of the asteroid flying by like a race car.]

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At NASA’s Kennedy Space Center in Florida, USA, the Orion vehicle that will be used for Artemis II is getting ready for this first mission to bring humans around the Moon and back in over 50 years. 

The vehicle consists of several parts: the conical crew module on top, where the four astronauts will live during the mission; the crew module adapter directly beneath it, connecting the crew module above and service module below; the cylindrical European Service Module, the powerhouse of Orion providing the crew vehicle with electricity, propulsion, thermal control, air and water; and the conical spacecraft adaptor, which connects Orion to the Space Launch System mega Moon rocket. 

The Artemis II vehicle stack was moved into a vacuum chamber at the Kennedy Space Center, where it will undergo several tests to ensure it can withstand the harsh conditions of space. The electromagnetic compatibility and interference tests as well as high-altitude vacuum tests will take place in one of two historical chambers also used to test spacecraft during the Apollo era.