Scientists confirm Einstein’s supermassive black hole theory

This artist's impression provided by the European Southern Observatory in July 2018 shows the path of the star S2 as it passes close to the supermassive black hole at the center of the Milky Way galaxy. (AP)
Updated 28 July 2018
0

Scientists confirm Einstein’s supermassive black hole theory

  • The black hole is 26,000 light years away from Earth and has a mass 4 million times that of the Sun
  • This showed the star’s orbital velocity increasing to more than 25 million kph (15.5 million mph) as it approached the black hole

BERLIN: A team of international scientists observing a star in the Milky Way have for the first time confirmed Einstein’s predictions of what happens to the motion of a star passing close to a supermassive black hole.
Einstein’s 100-year-old general theory of relativity predicted that light from stars would be stretched to longer wavelengths by the extreme gravitational field of a black hole, and the star would appear redder, an effect known as gravitational red shift.
“This was the first time we could test directly Einstein’s theory of general relativity near a supermassive black hole,” Frank Eisenhauer, senior astronomer at the Max Planck Institute for Extraterrestrial Physics, told journalists.
“At the time of Einstein, he could not think or dream of what we are showing today,” he said.
A team of scientists at the European Southern Observatory started monitoring the central area of the Milky Way using its Very Large Telescope to observe the motion of stars near the supermassive black hole 26 years ago.
The black hole is 26,000 light years away from Earth and has a mass 4 million times that of the Sun.
The scientists selected one star, S2, to follow. With an orbit of 16 years, they knew it would return close to the black hole in 2018.
Over 20 years, the accuracy of their instruments has improved and so in May 2018, they were able to take extremely precise measurements in conjunction with scientists from around the world.
This showed the star’s orbital velocity increasing to more than 25 million kph (15.5 million mph) as it approached the black hole.
The star’s wavelength stretched as it sought to escape the gravitational pull of the supermassive black hole, shifting its appearance from blue to red, Odele Straub from the Paris Observatory said.
The scientists now hope to observe other theories of black hole physics, she said.
“This is the first step on a long road that the team has done over many years and which we hope to continue in the next years,” MPE’s Reinhard Genzel, who led the international team, said.


Ivory Coast looks to solar vehicles to replace bush taxis

Updated 23 September 2018
0

Ivory Coast looks to solar vehicles to replace bush taxis

  • A switch to solar and durables may appear paradoxical in Jacqueville, however, as the area produces the lion’s share of the country’s gas and oil
  • Ivory Coast is targeting an 11-percent share of national consumption for renewables by 2020

JACQUEVILLE, Ivory Coast: Hi-tech, cheap — and quiet. The Ivorian resort of Jacqueville just outside Abidjan is betting on solar-powered three-wheelers as it looks to replace traditional but noisy and dirty bush taxis.
“It’s cheaper and relaxing!” says local trader Sandrine Tetelo, of the Chinese-made “Saloni” or “Antara” tricycles, which could eventually spell the end for old-school “woro-woro” four-wheelers as Jacqueville looks to make itself Ivory Coast’s premier eco city.
The mini-cars, 2.7 meters (8.8 feet) long and two meters high, are covered in solar panels each fitted out with six 12-volt batteries, giving the vehicles a range of 140 kilometers (87 miles).
Returning from a visit to China, the solar cars’ promotor Marc Togbe pitched his plan to mayor Joachim Beugre, who was immediately sold.
“We are used to seeing (typically old and beaten up) bush taxis pollute the atmosphere and the environment. We said to ourselves, if we could only replace them by solar trikes,” said Beugre.
“The adventure started in January with two little cars,” added Togbe, who has created a partnership with local businessman Balla Konate.
“I went to China with a friend,” says Konate, “and afterwards I sent four youngsters to Lome for training with a friend who had spoken to me about the project.”
He wants to extend operations to Odienne and Korhogo, towns in the north, the country’s sunniest region.
“Today, a dozen cars are up and running. We are right in the test phase. More and more people are asking for them,” says Beugre, seeing a chance to kill several birds with one solar stone.
Long isolated, his town, nestled between a laguna and the sea, has flourished in terms of real estate and tourism since the 2015 inauguration of a bridge linking Jacqueville to the mainland and cutting transit time to Abidjan to less than an hour.
For the start of the school year in October, Jacqueville plans to bring on stream a 22-seater “solar coach” designed to help deal with “the thorny issue of pupils’ transport.”
Many schoolchildren typically have to travel tens of kilometers from their home village to urban schools.
So far, the trikes have also provided work for around 20 people including drivers and mechanics.
“We’re on the go from six in the morning and finish around 10 or even midnight, weekends too,” says Philippe Aka Koffi, a 24-year-old who has been working as a driver for five months.
“It’s pleasant for doing your shopping more quickly,” says an impressed passenger, Aholia Guy Landry, after riding in a vehicle which can carry four people, driver included.
A big plus is the 100 CFA francs (0.15 euros/$0.18) price of a trip — half a typical downtown “woro-woro” fare — helping to attract between 500 and 1,000 people a day, according to the town hall and promoter.
A switch to solar and durables may appear paradoxical in Jacqueville, however, as the area produces the lion’s share of the country’s gas and oil.
The wells outside the town produce 235 million cubic feet of gas per day, while several foreign firms run pipelines taking oil and gas across the town to feed the refineries at Abidjan.
But the municipality — total budget 140 million CFA francs — sees none of the profits, an issue which has drawn public ire in the past.
The 50-million-CFA trike project is just one piece in a much larger jigsaw which includes the construction of a new eco city on a 240-hectare site among coconut trees.
“It will not be a city for the rich,” insists Beugre, showing off a blueprint replete with cycle paths and a university.
“All social strata who respect the environment will be able to live there,” he adds.
Yet at national level, such plans are conspicuous by their absence.
Ivory Coast, west African leader in electricity production — 75 percent of which comes from thermal energy and the remainder from hydroelectric dams — is targeting an 11-percent share of national consumption for renewables by 2020.
Even though by September the country had burned through barely one single megawatt of solar energy for this year, Beugre is undaunted.
“Our ecological project will go all the way” and “stand up to the power of oil and gas,” says the cowboy-hatted local politician.
“In years to come, we want to ensure that these solar-power machines become the main means of travel in the area.”