In the southern Milky Way, a galaxy collision has been uncovered by an international team of astronomers, one of whom is Michelle Cluver from the University of the Western Cape. This is the closest such “collisional ring” galaxy system ever detected.
The team of astronomers, led by Prof. Quentin Parker at the University of Hong-Kong and Prof. Albert Zijlstra at the University of Manchester, includes Dr Michelle Cluver from the University of the Western Cape. Their peer-reviewed paper appeared today in the Monthly Notices of the Royal Astronomical Society publication and details the discovery and description of this galaxy “train wreck.” It has been dubbed “Kathryn’s wheel” both after the famous fireworks that the system resembles, but also after the wife of the paper’s second author.
Such cosmic fireworks are very rare and arise from “bulls-eye” collisions between two galaxies of similar mass. Shock waves from the collision compress previously dormant reservoirs of gas and trigger the formation of new stars. This creates a spectacular ring of intense emission, and lights up the system like a Catherine wheel firework.
Kathryn’s Wheel was discovered during a wide-field optical survey of the Milky Way. The survey had been looking for the remnants of dying stars in our Galaxy, and the authors were very surprised to also find this example of a cosmic “ring of fire”, only about 30 million light years from us. This makes it seven times closer than the previous nearest example, and forty times closer than the famous ‘Cartwheel’ example of such systems. The galaxy is located behind a dense star field and close to a very bright foreground star, which is likely why its true nature had not been noted before. In addition, this appears to be a relatively empty region of space, making the chances of such a collision at this location very low.
Professor Parker said, “Not only is this system visually stunning, but it is close enough to be an ideal target for detailed study. The ring is also quite low in mass – a few thousand million Suns or less than 1% of the Milky Way – so our discovery shows that collision rings can form around much smaller galaxies than we thought.”
Dr Cluver added: “Further detailed studies of this system will help us learn more about the physics of shocks under these conditions, which may apply to a range of different astrophysical phenomena. In particular we are interested in how energy is dissipated from shocks to star formation.”
Smaller galaxies are more common than large ones enabling the authors to revise upwards the estimated number of such curious but rare phenomena by a factor of ten. They also find that Kathryn’s Wheel is probably the nearest collisional ring.
Prof. Q.A.Parker, Dr D.J.Frew and Dr I.Bojicic (HKU)
Prof. Albert Zijlstra and Dr George Bendo (University if Manchester)
Dr. Milorad Stupar (University of Western Sydney/Macquarie University)
Dr Michelle Cluver (University of the Western Cape)
Deezer to host Hotstix’s Mandela tribute playlist
Deezer is celebrating Nelson Mandela on the centenary of his birthday by hosting a tribute playlist created by music legend Sipho “Hotstix” Mabuse.
Mabuse, a legendary figure in African music, first rose to prominence in the 1970s with his band Harari and later developed a name for himself as a solo artist. One of his best known songs was the global hit BurnOut in the 1980s.
The playlist takes the listener on a captivating musical journey through the life of Nelson Mandela. It was compiled by Mabuse, who consulted with Mandela’s family and friends to ensure that the music would be relevant and accurate. The playlist also features commentary by Mabuse, which was recorded in his Soweto home.
“I have tried to tell the story of the music that Madiba loved,” says Mabuse. “The Playlist excludes the time in prison obviously, as Madiba would not have had exposure to music in that time. We have focused on the music we know he loved before and after that period. This recording was really an emotional journey for me, but an incredible opportunity to document these memories.”
The playlist features the music the young Mandela loved, such as The Manhattan Brothers, Solomon Linda, Brenda Fassie and Miriam Makeba. It includes struggle songs from Chicco, Johnny Clegg, Hugh Masekela and Yvonne Chaka Chaka. The playlist also includes Mandela by Zahara, one of the younger artists who caught Madiba’s ear.
Mabuse also offers stories of his own songs, such as Shikisha, a song greatly beloved by the former President.
“I was delighted to share my thoughts and hope the listeners enjoyed the musical journey,” says Mabuse. “Madiba did enjoy music immensely and we all have a purpose wherever we are in the world to celebrate culture and to learn from different cultures and music forms and styles.”
This playlist was inspired by the Nelson Mandela 100 campaign, calling on corporates and individuals to act as sources of inspiration and engage in conversation and action.
Sports streaming takes off
Live streaming of sports is coming of age as a mainstream method of viewing big games, as the latest FIFA World Cup figures from the UK show. Africa isn’t yet at the same level when it comes to the adoption of sports streaming, but usage is clearly moving in the right direction.
England’s World Cup quarter-final against Sweden was watched by just under 20 million viewers in the UK via BBC One. While this traditional broadcast audience was huge, it was streaming that broke records: the game was the BBC’s most popular online-viewed live programme ever, with 3.8 million views. In Africa, the absolute numbers are lower but the trend towards streaming major sports events on the continent is also well under way.
According to DStv, live streaming of sports dominates the usage figures for its live and recorded TV streaming app, DStv Now. The number of people using the app in June was five times higher than a year ago, with concurrent views peaking during major football and rugby games.
Since the start of the World Cup, average weekday usage of DStv Now is up 60%. The absolute peak in concurrent usage for one event was reached on 26 June, during the Nigeria vs Argentina game. The app’s biggest ever test was on 16 June with both Springbok Rugby and World Cup Football under way at the same time, resulting in concurrent in-app views seven times higher than the peaks seen in June last year.
The World Cup has also been a major reason for new users to download and try out the app. First-time app user volumes have tripled on Android and doubled on iOS since the start of the tournament.
“While we expected live sports streaming to take off, it’s also been pleasing to see that the app is really popular for watching shows on Catch Up,” says MultiChoice South Africa Chief Operating Officer Mark Rayner. “Interestingly, some of the most popular Catch Up shows are local, with Isibaya, Binnelanders, The Queen and The River all getting a significant number of views.”
With respect to app usage, the web and Android apps are the most popular way to watch DStv Now, with Android outpacing iOS by a factor of 2:1.
“We’re continuing to develop DStv Now, with 4k streaming in testing and smart TV and Apple TV apps on their way shortly,” says Rayner. “The other key priority for us is working with the telcos to deliver mobile data propositions that make watching online painless and worry-free for our customers.”
The DStv Now app is free to all 10 million DStv customers in Africa. The app streams DStv live channels as well as supplying an extended Catch Up library. Two separate streams can be watched on different devices simultaneously, and content can also be downloaded to smartphones and tablets. The content available on the app varies according to the DStv package subscribed to.