Hubble celebrates 34 years in orbit with a new photo of the Little Dumbbell Nebula

The Little Dumbbell Nebula
Click for original image.

Cool image time! To celebrate the 34th anniversay of its launch in 1990, astronomers have used the Hubble Space Telescope to take a new photo of the Little Dumbbell Nebula (also known as M76), located about 3,400 light years away and one of the most well-known planetary nebulae in the sky.

That picture is to the right, cropped, reduced, and sharpened to post here. From the caption:

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 disk 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 disk 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 250,000 degrees Fahrenheit, 24 times our Sun’s surface temperature. 
The sizzling white dwarf can be seen as a pinpoint in the center of the nebula. A star visible in projection beneath it is not part of the nebula.



Pinched off by the disk, 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 disk. They are being propelled by the hurricane-like outflow of material from the dying star, tearing across space at two million miles per hour.

Since launch Hubble has made 1.6 million observations of over 53,000 astronomical objects, and continues to be in high demand by astronomers, with only one request in six able to get time on the telescope. Not surprisingly, almost all of Hubble’s biggest discoveries were unexpected. Its future right now rests with its last three working gyroscopes used to orient it precisely. When one more fails, it will go to one-gyro mode, which will limit the precision of that orientation significantly. At that point the sharpness of the telescope’s imagery will sadly decline.

The only comparable orbital optical telescope now planned is China’s Xuntian optical telescope, scheduled for launch next year. It will fly in formation with the Tiangong-3 space station, allowing astronauts to periodically do maintenance missions to it. As I noted many times previously, American astronomers better start learning Chinese, assuming China even allows them access. Nor will these American astronomers have a right to complain, as it was their decision to not build a Hubble replacement, in their 2000, 2010, and 2020 decadal reports.

China delays till ’25 the launch of its Hubble-class optical space telescope

China today revealed that it is delaying the the launch of its Xuntian space telescope from early next year to 2025.

Zhan Hu, project scientist of Xuntian space telescope system, revealed that the delay was necessary for the team to finalize a preflight “engineering qualification model.” This model will undergo rigorous performance tests early next year. Despite the setback, China is making significant strides by domestically developing all five instruments for Xuntian, a first for the country, Scientific American reported.

The optical telescope, designed to somewhat comparable to Hubble, is intended to fly close to China’s Tiangong-3 space station where astronauts will periodically fly over to do maintenance and repair. Its primary mirror, two meters in diameter, is only slightly smaller than Hubble’s 2.4 meter mirror.

The article says the launch was supposed to happen before the end of this year, but that is incorrect. The launch has been targeting the spring of 2024 since February.