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SA observatory helps in rare find

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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.

EtaCarinae

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 digital prospects shine

South Africa is awaiting the arrival of not one but three international data centres, each representing a major hyperscale provider.

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Suffice to say, SA and its neighbours will soon have access to the same digital power, flexibility and reduced costs that makes the likes of Google, Facebook and Netflix possible.

It’s not an isolated event but in response to the market’s appetites. Companies large and small are rethinking and rebuilding their data centres, moving to massive hosting sites, using public cloud services, and investing in more specialised private systems. Not long ago this was the message brought to a reluctant market, but by 2018 the adoption of modern technologies – collectively called Digital Transformation – is in full swing.

There are many challenges facing our country, but we are also seeing important gains. The fast growth of fibre, refreshing new attitudes around mobile data, and proactive moves by Government are all pushing digital’s momentum in the right direction. Digital is prompting both foreign investment and massive expansions by local companies.

According to an International Data Corp (IDC) report, the local IT industry is outperforming other parts of the economy and is a real job creator. Much of this is due to cloud adoption, which moots suspicions that digital technology will reduce employment. In contrast, it shapes a smarter business environment, which is more productive and innovative. This grows economies and creates work.

What does it mean for 2019? The IT sector is still a small part of SA’s GDP, but that view doesn’t take in the knock-on effect of technology. For example, you can now apply for an ID or passport online, a big step forward from the stifling queues that many had to take time off from work to attend. Local services are taking on international rivals in the taxi and entertainment sectors. There has been a steady bubbling of startups taking SA innovations to international markets. Smarter farms, smarter taxis, smarter cities, smarter mines – digital is rippling through our society.

That ripple will continue to grow and reverb in 2019 – of that, I have no doubt. Today we have many local use cases where businesses and services have changed how they serve their markets. This is silencing digital’s critics as well as giving clear pathways to transformation. Making the switch is not easy. It takes leadership and an appetite for change and its challenges. But the practical proof is out there for all to see and the ways to accomplish it are clearer than ever before.

Meaningful change requires a certain level of strife. We can use this idea to colour our expectations for 2019. We can’t deny that it will be a tough year as the repercussions of a struggling economy start making themselves felt. But that means for the enlightened and proactive there will be opportunities for change as well. The groundwork for that shift is, as I explained earlier, already in place.

2019 will be tough, but it will also see SA flex its digital muscles. These are ready for primetime in a society that increasingly appreciates the relationship between digital technology and our wellbeing. The arrival of Azure, AWS and other international data centres to the market show that foreign investors see that potential. In 2019 South African society will start seeing it as well.

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ERP needs asset management

A single, integrated EAM and ERP solution can power an asset-intensive business into the future, says MOHAMED CASSOOJEE, MD and Country Manager, IFS South Africa and Africa.

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Most Enterprise Resource Planning software originated in the manufacturing sector as materials resource planning (MRP) solutions for organisations that needed to manage a lot of inventory. From there, they were rapidly developed into solutions for every industry imaginable.

But these roots mean that most standalone ERP software isn’t quite enough on its own to address the needs of organisations in asset-intensive industries such as metal foundries, mining, oil and gas, pulp and paper, energy and utilities, and construction and engineering.

Companies in these sectors are not managing inventory as much as they are managing the capacity of a fixed asset over its lifecycle as well as handling large-scale infrastructure projects with long planning cycles. This is where enterprise asset management (EAM) comes into play, offering capabilities that are not found in typical ERP systems.

EAM systems are built to help organisations manage assets such as plants, heavy machinery, pipelines and industrial-class vehicles. These solutions enable organisations to track the location and status of assets and asset objects in real time, schedule work orders to maintain and fix the assets, and manage the storage of spare parts required to service them.

As Africa’s governments, state-owned enterprises and private sector step up infrastructure investment, EAM has a vital role to play in ensuring that organisations drive the highest possible value from their new assets, whether these are telecoms networks, railway systems, ports or power plants.

According to the World Bank, Africa needs to spend around $93 billion a year over the next decade to address its infrastructure backlogs — about one-third of that cost is for maintenance. In 2008, World Bank found that about 30% of the infrastructure assets of a typical African country needed rehabilitation.

These numbers point to the urgent need for organisations across the continent to take a more proactive and preventative outlook towards maintenance of their key infrastructure and assets. Implementation of EAM can enable organisations to better track, manage and maintain assets to prolong their lifespan and enhance return on investment.

From asset planning to construction to operation to decommissioning and replacement, EAM allows organisations to maintain, manage and optimise assets over the entire asset lifecycle. By helping companies to increase asset productivity and availability – while reducing total cost of ownership – EAM can have a direct impact on profitability and financial sustainability.

Good EAM solutions can also be paired with corporate performance management and analytics tools to let organisations analyse operation disruptions and determine and address the causes, such as maintenance issues, inadequate training, or design faults.

Technological advances, along with the associated price drop for smart products being developed for the Internet of Things (IoT), now make it possible to monitor almost any asset in real-time from nearly any location across the globe. This further boosts the power and usefulness of an EAM solution. It is imperative that the EAM solutions that are implemented are built on robust, newer technologies that can easily support IOT, AI and smart bots.

EAM and ERP: a critical partnership

To sum up, ERP manages business operations, while the EAM system manages all the monitoring and operations of the asset. That means for most companies it isn’t an either-or choice because they need both EAM and ERP to drive optimal business performance.

Some organisations opt for so-called ‘best of breed’ EAM and ERP solutions from different providers. Yet integration can be a headache. The challenges include master data synchronisation and transaction integration. The company may also need to consider whether the ERP or EAM system is the better fit for a particular transaction or asset type.

However, for most organisations in asset-intensive industries, the ideal solution is an ERP system with extensive EAM capabilities: a system built from the ground up to manage not only basic business functions but also assets and their maintenance. Such a solution provides one complete solution spanning key processes and data.

This approach enables the organisation to truly manage and maximise value over asset lifecycles. It also empowers the enterprise to organise operations around the assets and individual asset objects it uses to create value for stakeholders, customers and the community.

For most asset-intensive companies, delivering EAM capabilities as part and parcel of an integrated ERP solution, simplifies their business systems landscape, giving them a single source of truth. The same arguments apply to project management and workforce management systems.

Organisations seeking to transform their business by standardising processes and leveraging reliable, real-time data will benefit from an ERP system with all of these capabilities, setting them up to adopt IoT, artificial intelligence, or whatever other new technologies are coming up next.

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