The Cat's Paw Nebula is a region of massive star formation
A newborn, massive star was formed some 4 000 light years from Earth in the Cat’s Paw Nebula (NGC 6334), a region of massive star formation.
This exciting conclusion was the result of many hours of observation, sighting, detection, and studying and monitoring readings at the Hartebeesthoek Radio Astronomy Observatory (HartRAO).
What is now HartRAO was originally built in 1961 as a tracking station for lunar and other solar system missions, and was operated by the Council for Scientific and Industrial Research on behalf of the National Aeronautics and Space Administration (Nasa). In 1974, when Nasa left, it was re-purposed for radio astronomy, and from 1999 it functioned under the National Research Foundation, an entity of the department of science and technology. Today HartRAO is a multidisciplinary facility for radio astronomy and space geodesy (the measurement, representation and orientation of Earth), exploiting the synergies between various disciplines.
Since 1961, there have been many interesting discoveries made at HartRAO, including an “earthquake” on a neutron star, flaring extragalactic sources and episodic and periodic masers.
Although the telescope is only 26m in diameter, it fulfils a niche function. It can carry out long-term monitoring programmes, do quick response surveys, and participate in experiments where telescopes are linked globally, all while teaching future generations of astronomers.
Massive stars, much bigger than our sun, are born inside clouds of dust and gas, rather like rain droplets form in clouds. The clouds are so dense that not even the world’s best optical telescopes — America’s space-based Hubble Telescope or the Southern African Large Telescope — can see stars inside them.
Bear in mind that the Cat’s Paw Nebula is a region of massive star formation. The illuminated regions are the result of gigantic stars heating nearby gas. Stars are born in the areas of darkness, and can only be detected using infrared telescopes, or radio telescopes like the one at HartRAO.
We used the phenomena of masers (which act in a similar way to lasers, only at radio wavelengths) to search areas where stars are born. Masers are excellent probes for monitoring star-forming regions. What transpired?
A major event was recently discovered near the massive star-forming region NGC 6334 F. Many different masers found in this region, some never seen before, suddenly brightened in unison shortly after February 17 2015.
One possible explanation is that a star was born in the background and ionised the gas and dust that the masers are amplifying; something never seen before, let alone monitored. Give or take 1 000 years, the news of the birth has taken 4 000 years to reach Earth, implying that the star was actually born sometime in February 2000 BC. Exciting stuff — if it is true.
A less exciting possibility is that an existing protostar ionised the gas and dust behind the masers but, whatever the cause, we continue to monitor the source and are working with groups of astronomers in Japan, Korea and Australia to discover more.
Dr Gordon MacLeod is an expert in star formation and business consulting, who has recently rejoined the staff at HartRAO after a 19-year absence. Professor Derek Smits is the head at the Astonomy department at Unisa, and is a renowned researcher in a range of astronomi