Under the leadership of Pavel Mancera Piña (University of Groningen and ASTRON), an international team of astronomers has discovered six dim dwarf galaxies that contain hardly any dark matter. This is rare, as it is expected that most of the dim dwarf galaxies are only held together by means of a large amount of dark matter. The researchers will soon publish their findings in The Astrophysical Journal Letters .
For their research, the astronomers used the satellite dishes of the Dutch Westerbork Synthesis Radio Telescope and those of the American Very Large Array. They looked at six dim dwarf galaxies between 240 million and 320 million light years away. Until now, this type of galaxy has not been studied much because it does not emit much light.
The name ‘dwarf galaxies’ refers to the weak light produced by the galaxies, not to their size. They are actually just as big as our own Milky Way, but contain far fewer stars. The prevailing idea is that such large dwarf galaxies can only exist if they are held together by dark matter.
But to the surprise of the researchers, after studying the dwarf galaxies, it appears that the dim dwarf galaxies and their environments don’t contain any dark matter. According to current theories, these six galaxies are therefore unable to exist.
In their scientific publication, the researchers posit a few explanations for the absence of dark matter, but in fact – as they say themselves – they still haven’t come up with a good explanation.
Two galaxies containing little dark matter were previously found by another research group. Far more details are known about the six new galaxies.
Last week, Ben Feringa and Anouk Lubbe presented the first copy of their book Alledaagse Moleculen (Everyday Molecules) to minister Robbert Dijkgraaf. The richly illustrated book offers an accessible overview of 180 substances in our daily lives....
Dr Annette Scheepstra of the UG Arctic Centre, part of the Faculty of Arts, is about to conduct research into tourism in Antarctica and how tourists can become Antarctic ambassadors. She has been granted €1 million in funding by the Dutch Research...
The Royal Netherlands Academy of Arts and Sciences (KNAW) has appointed Professor Maria Loi and Professor Dirk Slotboom from the Faculty of Science and Engineering as members of the Academy.
The UG website uses functional and anonymous analytics cookies. Please answer the question of whether or not you want to accept other cookies (such as tracking cookies).
If no choice is made, only basic cookies will be stored. More information