The Hubble telescope has captured another stunning image of the nebula NGC3603 within our Milky Way. The cluster is known to be one of the largest star formation areas and is located in the Carina spiral arm of the Milky Way, about 20 000 light-years from the Solar System. According to the ESA website where I found this article, astronomers have been watching this cluster for some time. The cluster contain stars of varying age and the image below shows the gas cloud formation where the stars are born.
NGC 3603 was first discovered by Sir John Herschel in 1834. It is known to harbour a blue supergiant star called Sher 25, believed to be on the verge of exploding as a supernova. It is often known as the Milky Way counterpart of the predecessor of the now-famous supernova SN 1987A in the Large Magellanic Cloud.
As you can see, most of the stars are giving off an ultraviolet blue light which indicates that they are young stars. The radiation of these stars is creating a solar wind that has generated a cavity in the gas cloud around these stars pushing away the pillars within which the necessary minerals, gasses and debris are located for new star formations.
Why is this of interest to astronomers? Well lets start with the image and how it shows many stars with varying mass. The colouration of the stars also indicate that they were created within the same timeframe. Stars of different masses evolve at a different pace, and hence change their colouration at different rates, so this star cluster makes it possible to study several types of stars at varying stages in their lives, in detail. Astronomers can compare clusters of different ages with one another and determine which properties (such as temperature and brightness) change as the stars get older.
Dr Jesús Maíz Apellániz from Instituto de Astrofísica de Andalucía, Spain, is leading the Hubble investigation and according to ESA's article, 'the cluster appears to gather the most massive stars at its core. His team has discovered that the distribution of different types of stars at the centre of this dense cluster is similar to that of other young clusters in the Milky Way'. The team has also found that a number of stars within this cluster have exceeded known theoretical limits to mass. One theory put forward to explain this is that there may be multiple stars in close proximity from which the light being emitted is combining to give the appearance of a single star. At a distance of 20,000 light years, Hubble's resolution is not fine enough to separate out each light source and hence astronomers are second guessing on whether this theory tests positive.
The swirling nebula of NGC 3603 contains around 400 000 solar masses of gas. Lurking within this vast cloud are a few Bok globules, named after Bart Bok who first observed them in the 1940s. Bok globules are dark clouds of dense dust and gas with masses of about ten to fifty times that of the Sun. They resemble insect cocoons and are in the process of collapsing under their own weight, forming new stars. Bok globules appear to be some of the coldest objects in the Universe.
0 comments:
Post a Comment