This new image from NASA’s Hubble Space Telescope, shows the tentacled Southern Crab Nebula. The nebula, officially known as Hen 2-104, appears to have two nested hourglass-shaped structures that were sculpted by a whirling pair of stars in a binary system. The duo consists of an aging red giant star and a burned-out star, a white dwarf. The red giant is shedding its outer layers and some of this ejected material is attracted by the gravity of the companion white dwarf. The result is that both stars are embedded in a flat disk of gas stretching between them. This belt of material constricts the outflow of gas so that it only speeds away above and below the disk. The result is an hourglass-shaped nebula. The bubbles of gas and dust appear brightest at the edges, giving the illusion of crab leg structures. These “legs” are likely to be the places where the outflow slams into surrounding interstellar gas and dust, or possibly material which was earlier lost by the red giant star. (NASA and ESA)
The Hubble Space Telescope, arguably the jewel in the crown of NASA’s science missions, was launched 29 years ago. It has been providing scientists and the public with a steady stream of previously unimagined insights about the cosmos — plus those jaw-dropping, very high-resolution images like the one above — pretty much ever since.
It has also provided the best example to date of what humans can do in space with its five repair and upgrade missions. It did indeed launch to great skepticism, especially after a near fatal flaw was found in its key mirror. It was also considered over budget at launch, way behind schedule and questionable scientifically and had to be fixed in orbit 353 miles into space.
The Hubble Space Telescope after its second repair and upgrade mission in 1998. (NASA)
But almost three decades into its mission now — and with decades more service likely — it clearly shows what an exceedingly ambitious project can deliver and the level of excellence that NASA, its European Space Agency partner and space scientists and engineers can achieve. Talk about soft power.
This is important to remember as the agency’s 40-year-old Great Observatories program –that the Hubble Telescope is a part of –is under considerable threat.
The mission that was supposed to fly in the 2010s, the James Webb Space Telescope, is also way over budget, way behind schedule, and now described as a financial threat to other NASA missions. … Read more
