NKALAKATHA
ASTRONOMERS DISCOVER MEGAMASER ‘NKALAKATHA’ USING MEERKAT Let MeerKAT tell stories of the murky underbelly of astronomy. By: Lusanda Tamesi
Megamasers… Megamasers are super powerful space lasers that emit radio
‘Mega’-which means big or very large refers to the size of masers
waves and are caused by dense gas created when two galaxies
like the one discovered by MeerKAT – the emission is so bright it
collide and merge together.
could be seen from 5 billion light-years away! This requires a lot of hydroxyl gas, and this amount of gas is created when
Let's break down the word 'megamaser'. First, we have a 'maser',
two galaxies collide and merge to form a bigger galaxy. This
which is much like a laser. Megamasers act as an astronomical
merger creates a large amount of dense gas, including hydroxyl,
laser that beams out microwave or radio emissions rather than
and this is the condition for a megamaser.
visible light. Since megamasers are the result of galaxy mergers, they are a IN MORE DETAIL: While lasers are seen in visible or infrared
useful marker for identifying and studying merger galaxies and
light, masers are seen in microwave or radio waves. Masers in
galaxy evolution.
space can be created by gas; in this case, this is a hydroxyl maser. Hydroxyl (-OH) is a molecule made of one atom of
On 7 April, media houses were buzzing with captions like
hydrogen (H) and one atom of oxygen(O). When there are a lot
“Megamaser ‘Nkalakatha’ discovered by astronomers using
of hydroxyl molecules, this emission cycle builds up quickly and
MeerKAT”, and “Breakthrough, as ’big boss’ megamaser discovered
causes the maser emission to be seen with a radio telescope,
by MeerKat telescope”. For some odd reason naming the mega-
such as MeerKAT.
maser ‘’Nkalakatha” was somehow ‘unusual’ as some can not even pronounce it. Some in the entertainment industry thought that South African Kwaito artist Mandoza had made a comeback!
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African Science Stars Issue 3 | www.assap.co.za
