‘Dying star’ keeps on coming back big time

Hunting Africa’s Einstein

CAPE CANAVERAL, Florida, Nov 9, (Agencies): Death definitely becomes this star.

Astronomers reported Wednesday on a massive, distant star that exploded in 2014 — and also, apparently back in 1954. This is one supernova that refuses to bite the cosmic dust, confounding scientists who thought they knew how dying stars ticked.

The oft-erupting star is 500 million light-years away — one light-year is equal to 5.9 trillion miles (9.5 trillion kilometers) — in the direction of the Big Bear constellation. It was discovered in 2014 and, at the time, resembled your basic supernova that was getting fainter.

But a few months later, astronomers at the Californiabased Las Cumbres Observatory saw it getting brighter. They’ve seen it grow faint, then bright, then faint again five times. They’ve even found past evidence of an explosion 60 years earlier at the same spot.

Supernovas typically fade over 100 days. This one is still going strong after 1,000 days, although it’s gradually fading.

The finding was published Wednesday in the journal Nature.

“It’s very surprising and very exciting,” said astrophysicist Iair Arcavi of the University of California, Santa Barbara who led the study. “We thought we’ve seen everything there is to see in supernovae after seeing so many of them, but you always get surprised by the universe. This one just really blew away everything we thought we understood about them.”

The supernova — officially known as iPTF14hls — is believed to have once been a star up to 100 times more massive than our sun. It could well be the biggest stellar explosion ever observed, which might explain its deathdefying peculiarity.

It could be multiple explosions occurring so frequently that they run into one another or perhaps a single explosion that repeatedly gets brighter and fainter, though scientists don’t know exactly how this happens.

Arcavi

Massive

One possibility is that this star was so massive, and its core so hot, that an explosion blew away the outer layers and left the center intact enough to repeat the entire process. But this pulsating star theory still doesn’t explain everything about this supernova, Arcavi said.

Harvard University’s astronomy chairman, Avi Loeb, who was not involved in the study, speculates a black hole or magnetar — a neutron star with a strong magnetic field — might be at the center of this never-beforeseen behavior. Further monitoring may better explain what’s going on, he said.

Las Cumbres, a global network of robotic telescopes, continues to keep watch.

Scientists do not know whether this particular supernova is unique; it appears rare since no others have been detected.

“We could actually have missed plenty of them because it kind of masquerades as a normal supernova if you only look at it once,” Arcavi said.

Nothing lasts forever — not even this super supernova.

“Eventually, this star will go out at some point,” Arcavi said. “I mean, energy has to run out eventually.”

A dozen other students look on as Umar Amadu uses a glass pipette to draw a solution from a conical flask as part of a chemistry experiment.

It could be a scene from any school laboratory around the world, but until two months ago Amadu and his fellow students had no access to any science equipment.

Science subjects at his rural secondary school outside the city of Katsina in northern Nigeria were taught using theory only.

But now they have all the kit they need to put theory into practice, thanks to a mobile science lab that tours selected state schools.

“It’s an exciting experience. We were being taught only the theoretical aspect of science subjects,” Amadu, who wants to be a doctor, told AFP.

“But with this project we now have a better understanding of what we are taught.”

The “Science on Wheels” project is the brainchild of international development charity Voluntary Service Overseas (VSO) and is supported by the consumer goods company PZ Cussons.

A truck equipped with laboratory equipment tours the state, allowing 7,500 students and 15 schools to conduct practical lessons.

Quality

It also aims to haul Nigeria up the rankings for the quality of its science and math teaching, after a World Economic Forum study ranked the country a lowly 131st out of 139.

The Katsina state government pays for the driver and fuel to take the truck to each school twice a week.

Katsina — the home state of President Muhammadu Buhari — was the first in mainly Muslim northern Nigeria to introduce so-called Western subjects in education in the 1940s.

But since then the sector has suffered from years of neglect and under-investment. Now, it has a substantial share of the more than 10 million out-of-school children in the north. About 16 billion naira ($45 million, 38 million euros) was allocated to education from Katsina’s 140.2-billion-naira budget this year.

According to state governor Aminu Bello Masari, the state has a deficit of 13,000 teachers, as there are currently just 5,200 for its 432 secondary schools. Only 123 of those schools have science labs. The state government has tried to address the teacher shortage by re-employing retired teachers and even deploying civil servants to classrooms to help out.

It has also tried to attract university graduates from the more educationally prosperous south, with postings to Katsina part of their mandatory one-year national service.

For the “Science on Wheels” project, VSO said it had to take on 60 science and math teachers to go to the 15 selected schools.

Amadu’s school, the Government Day Secondary School (GDSS) in Muduru, has 734 pupils but had only one teacher for its 157 science students.

School principal Sagir Ladan said the mobile science project has allowed it to take on three more and helped overcome lack of funding for infrastructure and laboratory supplies.

Poor funding is obvious from the classrooms at the school, most of which have no furniture, with students sitting on the floor or perching on broken window sills instead of desks.

VSO’s country director in Nigeria, Lucia Balonwu, said the charity’s project was a small step towards overall improvements.