We already have exoplanets, dwarf stars, and black holes, but the cosmic group gained a new type of object this week. At a conference of the American Astronomical Society in Pasadena, California, scientists announced the discovery “blue dotsBlue dots.
“It’s amazingly blue, and in the Hubble Space Telescope images it looks like — well, like blobs,” said Michael Jones of the University of Arizona. These are small and somewhat compact groups of a hundred thousand stars at most. Blue indicates that the stars are hot and young. The blue dots Yet it’s in a place where you wouldn’t expect newborn stars at all: alone in empty space, far from large galaxies like our Milky Way.
One such star cluster, called SECCO1, was discovered a few years ago by Jones’ colleague David Sand, but a handful have now been found. So there really is a new kind of thing.
Compare Jones blue dots With oases in the desert. The desert in which the “blobs” were found is the Virgo cluster, an enormous swarm of galaxies about 50 million light-years away. In such a cluster, the space between individual galaxies is filled with hot, vaporized gas – a very inhospitable environment. New stars can only form from shrinking clouds of cold gas, so don’t expect them to exist at all.
recycled materials
There is another crazy thing. Measurements using the European Very Large Telescope in Chile show that stars in blue dots It contains many relatively heavy elements. This means that they are made from recycled materials, which were already somewhat “polluted” by previous generations of stars. Strange, because the “blue blobs” are located hundreds of thousands of light-years away from large galaxies where such pollution may have occurred.
In an article about Astrophysical Journal Jones and his colleagues come up with a possible explanation. Suppose a galaxy on the outside plunges into a Virgo mass at high speed — a bit like someone is “bombing” into a swimming pool, Jones said. The cold (and polluting) gas in the system is then ejected by the hot gas in the block. Stars can then be formed from that dumped material.
According to Marin Franks of the Leiden Observatory, who was not involved in the research, it’s very exciting to see that there are more of these groups, as well as the first sample discovered from SECCO1. “The remarkable thing is that we don’t know what they can be compared to” — “young galaxies, or star clusters, or ‘streams’ of gas from the collisions,” Franks says. Franks is especially curious to know if the blue blobs also contain dark matter — mysterious things that astronomers only discover via gravity. This could shed more light on their origins.
