South African astronomers, together with collaborators from Moscow have discovered Luminous Blue Variable star. A very rare sighting as the star is very old and may soon blow apart causing a supernova explosion, one of the most powerful explosions in the Universe.
Astronomer Dr A. Kniazev from the South African Astronomical Observatory (SAAO), together with collaborators from the Lomonosov Moscow State University Dr V. Gvaramadze and Dr L. Berdnikov, has recently discovered a new example of an incredibly rare kind of star known as a Luminous Blue Variable star (LBV). Out of the billions of stars mapped in our skies, only sixteen confirmed Luminous Blue Variable stars are known to date. The star, named WS1, is the latest addition to this rare group of stars. LBV stars are of interest to astronomers because they are extremely old stars which may soon die and blow apart in a supernova explosion, one of the most powerful explosions in the Universe.
Just like humans, stars do not live forever. Once their fuel has run out they stop shining and die. Stars that are much more massive than the Sun end their lives in powerful supernova explosions which can outshine all the other billions of stars in their galaxy put together. We never know when or where one of these explosions will take place but we can keep an eye on those stars most likely to go supernova in the near future: Luminous Blue Variable stars. Luminous Blue Variables (LBVs) represent a stage in the evolution of very massive stars towards the end of their life. For stars with initial masses of between 20-25 times that of our Sun the LBV stage occurs just before the star dies in a spectacular supernova explosion. For even more massive stars, they pass through the LBV phase slightly earlier in their lifetimes, but those stars too will eventually die in a supernova explosion.
LBV stars are much hotter and therefore more luminous than our Sun. They are some of the most luminous stars known, with brightnesses ranging from 250,000 to 1 million times brighter than our Sun. As a consequence of their high mass they evolve very quickly and have – astronomically speaking – short lifetimes. LBV type stars have a total lifetime of around a few million years and spend much less than one million years in the LBV phase of their evolution. The LBV phase can be thought of as a “stellar retirement” for the most massive stars. The Sun for comparison has a total lifetime of around 9 billion years. Because the LBV phase is so short-lived you have to be incredibly lucky to catch a star at the LBV stage of its life. This explains why they are so rare compared with other types of star.
LBV stars are losing vast amounts of mass as their upper atmosphere streams off into space in a so-called “stellar wind”. These stars undergo random outbursts at their surfaces, spewing their outer atmosphere into space. These outbursts cause variations in their brightness which is one of the key observational signatures of such a star. Another consequence of their immense mass loss is the formation of a bipolar or circular nebula, or cloud, around the star composed of material that has been lost from the star’s atmosphere. These nebulae are found enveloping approximately 70% of confirmed LBV stars. Eta Carinae is a famous and well studied example of a LBV star with a beautiful bipolar nebula.
As most LBVs are enshrouded in a nebula, astronomers often look for possible LBV candidates by searching for such nebulae. In the case of WS1, Kniazev and collaborators were alerted to the possibility that the star could be a LBV because they found in 2011 that it is surrounded by a circular shell of material that emits light at infra-red wavelengths. This prompted them to make follow up optical observations of the central star to confirm whether or not the star was a LBV. In 2011, using the Southern African Large Telescope (SALT) they obtained a spectrum of the star (akin to a fingerprint) and found features in the spectrum typically associated with LBV type stars. However, this information was not sufficient to confirm whether WS1 was indeed a LBV. To do this, astronomers needed to observe the star over a long time period to confirm whether its variability in brightness and in its spectral features matched that expected from a LBV type star. Kniazev and collaborators continued to observe WS1 between 2013 and 2014 using the SALT telescope to look for changes in the star’s spectrum. They also monitored the star’s brightness between 2011 and 2014 using the South African Astronomical Observatory’s 1.9 m telescope and combined their observations with publicly available data spanning over forty years.
By combining the information from all their observations they found that WS1 did indeed exhibit all the observational characteristics of a LBV type star and concluded that WS1 is an incredibly rare Luminous Blue Variable star.
“We were very lucky to discover major spectral and brightness changes in WS1 without having to wait for too long”, says Kniazev. “With this discovery, we unambiguously proved the LBV status of this star. We expect that subsequent spectral analysis will allow us to determine fundamental parameters of WS1, for example its temperature and luminosity. We also hope to find more bona fide LBVs using SALT, which will help us to understand better the evolution of LBV type stars and their relation to other types of massive, old stars.”
This discovery, published as a Letter to Monthly Notices of the Royal Astronomical Society brings the total number of LBV stars known to date to sixteen.
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SA gets gaming awards
Reed Exhibitions Africa recently announced that the inaugural South Africa Gaming Awards will be hosted at Comic Con Africa 2019.
The South Africa Gaming Awards is set to become a key feature of Comic Con Africa and has been established to celebrate individuals, teams, developers, streamers, journalists and the like in the gaming industry. Categories and submission details will be announced early in 2019 for the awards which will take place in September.
Carol Weaving, Managing Director of Reed Exhibitions states: “On the back of the roaring success of the inaugural Comic Con Africa earlier this year we came to the realisation that there is no platform of this nature on the African continent where those who are excelling in the gaming industry have an opportunity to be acknowledged. We want to bring peers and like-minded individuals together to celebrate this industry and build this community across the board. To all future entries: Game on!”
Comic Con Africa 2019 will take place from 21 – 24 September 2019, at Gallagher Convention Centre in Midrand.
What tech’s 3 wise men tell us to expect
Advice from three wise men will lead SA into the 4th Industrial Revolution, writes ANDRIES BRINK, CEO of Andile Solutions
Over the past 50 years, 3 wise men made predictions that have become definitive in our time. Gordon Moore said data processing would double in capacity every 18 to 24 months, Mark Kryder predicted that data storage would expand at about the same rate, and George Gilder said the bandwidth connecting different nodes would double at three times that speed. Like the sages from the biblical story, they saw a massive star rising ahead of them.
Today we stand in the radiance of technology’s sun. My consumer grade phone is more powerful than most corporate data centres at the turn of the century. It has 200,000 times more memory than Voyager 2, which just left our solar system. In lockstep with this progress, today’s data centres produce decentralised processing power at incredibly cheap prices. These have found their way to humanity and are delivering on the promise of a new dispensation. Maybe LOCNVL had a point when they sang in 2010 that they had a sun in their pocket.
Let’s change our focus, for a moment, to Africa, which despite having nearly a billion people still only produces roughly $3.5 trillion in GDP. Apple, Alphabet, Amazon, Microsoft and Facebook have a collective market capitalisation of the same amount, yet do so with 0.08% of the number of people. To say Africa is missing out on the technology sun is an understatement. While everyone can benefit from this change, only a few will be positioned to lead it. It’s a fact quite visible wherever you look.
Over the centuries, we have learnt that only four composers (Bach, Beethoven, Mozart and Tchaikovsky) wrote almost all the music played by modern orchestras. Similarly, just a handful of authors sell all the books (of 1,5 million books published each year, only 500 sell more than a hundred thousand copies), and of the few scientists that actually publish papers that are accepted, only a very small percentage are then actually referenced by their peers. Business majors will note that this phenomenon was captured eloquently by 18th century Italian polymath Vilfredo Pareto and his 80/20 principle.
The question we should ask ourselves is: how can SA be part of the 20%, the mavericks that change the world instead of the 80% who end up as followers? For the answer, we need not look further than Lesetja Kganyago, the governor of our Reserve Bank:
“Lasting wealth… isn’t in a country’s soil but in its citizens’ heads. Countries get rich because people develop specialised skills, and because they find ways to cooperate so they can do things much too complex for any individual to do alone. To handle all this complexity and specialisation, people gather in firms, and firms interact in markets.”
He warned that when a state declares war against market mechanisms and wealth, it kills off investment and scares skilled people away. Natural resources don’t get used effectively, no matter how abundant they are, and the economy doesn’t develop other kinds of industries either.
It’s not hard to back this view: the mess in the DRC, the collapse of Zimbabwe, and the unbelievable accumulation of debt by Zambia reveal how disdain for market principles have hobbled what should be highly productive nations. Neither is it hard to find positive examples: India and Singapore have transformed their economies thanks to very business-friendly environments, and they have reduced poverty as well. The rise of the Asian Tigers had a lot to do with using market mechanisms effectively.
This brings us to the saviour part.
Minister Rob Davies recently declared that “there would be serious winners and losers due to the 4th industrial revolution (4IR).”, sounding vaguely familiar to a disturbing passages from the Holy Bible, a book that we can be certain the Minister did not mean to reference. In Matthew 13:12, Jesus says that:” For whoever has, to him more will be given, and he will have abundance; but whoever does not have, even what he has will be taken away from him.” (The reader should be aware that economists often refer to the Pareto principle as the Matthew principle in relation to the above)
A significant number of things have been taken away from South Africa during the Zupta era. Yet South Africa still has an incredible opportunity here:
Yes, since 2008 SA has plunged 22 spots from 45th position. Yet we are still in the game and can reverse the trend, particularly if we harness 4IR beyond mentions in speeches. To me the opportunity is obvious. We have the finance system, market size and innovation capability to create a hotbed for 4IR-fueled progress. Looking at my industry, we should find ways to bring the smartest fintechs to South Africa.
Therefore, during this festive season, let us listen to our favourite devices streaming Mozart and Beethoven whilst we study and embrace the wise words of Pareto and other trusted saviours. The governor has confirmed our course. If SA Inc. could open doors for that 0.08 % of innovators and give them a reason to bring their wealth and knowledge here, we can accomplish amazing things as a nation. The three wise men have shown us a great rising star that everyone, even our most Marxist ministers, can see on the horizon. In 2019, let’s hope, and pray, we can converge on the opportunity.