Rare ‘ring of fire’ solar eclipse to dim Africa, Asia

Skywatchers along a narrow band from west Africa to the Arabian Peninsula, India and southern China will witness on Sunday the most dramatic “ring of fire” solar eclipse to shadow the Earth in years.

Annular eclipses occur when the Moon — passing between Earth and the Sun — is not quite close enough to our planet to completely obscure sunlight, leaving a thin ring of the solar disc visible.

They occur every year or two, and can only be seen from a narrow pathway across the planet.



Remarkably, the eclipse on Sunday arrives on the northern hemisphere’s longest day of the year — the summer solstice — when Earth’s north pole is tilted most directly towards the Sun.

The “ring of fire” will first be seen in northeastern Republic of Congo at 5:56 local time (04:56 Greenwich Mean Time Zone) just a few minutes after sunrise.

This is the point of maximum duration, with the blackout lasting 1 minute and 22 seconds.


Arcing eastward across Asia and Africa, it will reach “maximum eclipse” — with a perfect solar halo around the Moon — over Uttarakhand, India near the Sino-Indian border at 12:10 local time (6:40 Greenwich Mean Time Zone).


More spectacular, but less long-lived: the exact alignment of the Earth, Moon and Sun will be visible for only 38 seconds.

“The annular eclipse is visible from about 2% of Earth surface,” Florent Delefie, an astronomer and the Paris Observatory, told Agence France-Presse.

“It’s a bit like switching from a 500-watt to a 30-watt light bulb,” he added. “It’s a cold light, and you don’t see as well.”

Good weather key

Animals can get spooked — birds will sometimes go back to sleep, and cows will return to the barn.

The full eclipse will be visible somewhere on Earth during just under four hours, and one of the last places to see a partially hidden Sun is Taiwan before its path heads out into the Pacific.

People hundreds of kilometers on either side of the centreline across 14 countries will also see light drain from the day, but not the “ring of fire.”

Weather conditions are critical for viewing.

“Good weather is the key to successful eclipse viewing,” astrophysicist Fred Espenak, an expert on eclipse prediction, commented on the National Aeronautics and Space Administration (NASA) Eclipse website. “Better to see a shorter eclipse from clear sky than a longer eclipse under clouds.”

A solar eclipse always occurs about two weeks before or after a lunar eclipse, when the Moon moves into Earth’s shadow. Lunar eclipses are visible from about half of Earth’s surface.

There will be a second solar eclipse in 2020 on Dec. 14 over South America. Because the Moon will be a bit closer to Earth, it will block on the Sun’s light entirely.

It will take less than 100 minutes for the path of this eclipse to move across the continent.

Even if the day has darkened, looking at a solar eclipse with the naked eye is dangerous.

Sunglasses — which don’t filter out Ultraviolet rays — do not offer any protection, Delefie warned.

“The Sun is so bright that even when there’s only a tiny portion visible, it is still dangerous for the eyes,” he said.

Agence France-Presse

NASA spacecraft rockets toward sun for closest look yet

CAPE CANAVERAL, Florida — A NASA spacecraft rocketed toward the sun Sunday on an unprecedented quest to get closer to our star than anything ever sent before.

The Parker Solar Probe will fly straight through the wispy edges of the corona, or outer solar atmosphere, that was visible during last August’s total solar eclipse. It eventually will get within 3.8 million (6 million kilometers) of the sun’s surface, staying comfortably cool despite the extreme heat and radiation, and allowing scientists to vicariously explore the sun in a way never before possible.

No wonder scientists consider it the coolest, hottest mission under the sun, and what better day to launch to the sun than Sunday as NASA noted.
“Fly baby girl, fly!!” project scientist Nicola Fox of Johns Hopkins University tweeted just before liftoff. She urged it to “go touch the sun!”


Protected by a revolutionary new carbon heat shield and other high-tech wonders, the spacecraft will zip past Venus in October. That will set up the first solar encounter in November. Altogether, the Parker probe will make 24 close approaches to the sun on the seven-year, $1.5 billion undertaking.

For the second straight day, thousands of spectators jammed the launch site in the middle of the night as well as surrounding towns, including 91-year-old astrophysicist Eugene Parker for whom the spacecraft is named. He proposed the existence of solar wind — a steady, supersonic stream of particles blasting off the sun — 60 years ago.

It was the first time NASA named a spacecraft after someone still alive, and Parker wasn’t about to let it take off without him. Saturday morning’s launch attempt was foiled by last-minute technical trouble.

“I’m just so glad to be here with him,” said NASA’s science mission chief, Thomas Zurbuchen. “Frankly, there’s no other name that belongs on this mission.”

The Delta IV Heavy rocket thundered into the pre-dawn darkness, thrilling onlookers for miles around. NASA needed the mighty 23-story rocket, plus a third stage, to get the diminutive Parker probe — the size of a small car and well under a ton — racing toward the sun.

From Earth, it is 93 million miles to the sun (150 million kilometers), and the Parker probe will be within 4 percent of that distance. That will be seven times closer than previous spacecraft.

Parker will start shattering records this fall. On its very first brush with the sun, it will come within 15.5 million miles (25 million kilometers), easily beating the current record set by NASA’s Helios 2 spacecraft in 1976. By the time Parker gets to its 22nd orbit of the sun, it will be even deeper into the corona and traveling at a record-breaking 430,000 mph (690,000 kilometers per hour).

Nothing from Planet Earth has ever hit that kind of speed.


Even Fox has difficulty comprehending the mission’s derring-do.

“To me, it’s still mind-blowing,” she said. “Even I still go, really? We’re doing that?”

Zurbuchen considers the sun the most important star in our universe — it’s ours, after all — and so this is one of NASA’s big-time strategic missions. By better understanding the sun’s life-giving and sometimes violent nature, Earthlings can better protect satellites and astronauts in orbit, and power grids on the ground, he noted. In today’s tech-dependent society, everyone stands to benefit.

With this mission, scientists hope to unlock the many mysteries of the sun, a commonplace yellow dwarf star around 4.5 billion years old. Among the puzzlers: Why is the corona hundreds of times hotter than the surface of the sun and why is the sun’s atmosphere continually expanding and accelerating, as the University of Chicago’s Parker accurately predicted in 1958?

“The only way we can do that is to finally go up and touch the sun,” Fox said. “We’ve looked at it. We’ve studied it from missions that are close in, even as close as the planet Mercury. But we have to go there.”

The spacecraft’s heat shield will serve as an umbrella, shading the science instruments during the close, critical solar junctures. Sensors on the spacecraft will make certain the heat shield faces the sun at the right times. If there’s any tilting, the spacecraft will correct itself so nothing gets fried. With a communication lag time of 16 minutes each way, the spacecraft must fend for itself at the sun. The Johns Hopkins flight controllers in Laurel, Maryland, will be too far away to help.

A mission to get close up and personal with our star has been on NASA’s books since 1958. The trick was making the spacecraft small, compact and light enough to travel at incredible speeds, while surviving the sun’s punishing environment and the extreme change in temperature when the spacecraft is out near Venus.

“We’ve had to wait so long for our technology to catch up with our dreams,” Fox said. “It’s incredible to be standing here today.”

More than 1 million names are aboard the spacecraft, submitted last spring by space enthusiasts, as well as photos of Parker, the man, and a copy of his 1958 landmark paper on solar wind.

“I’ll bet you 10 bucks it works,” Parker said. /ee

source: technology.inquirer.net

Earth braces for biggest space storm in five years

WASHINGTON - The biggest space weather storm in five years is hurtling toward Earth, threatening to disrupt power grids, GPS systems, satellites and airline flights, experts say.

The brunt of the storm is expected to strike early Thursday and last through Friday, possibly garbling some of Earthlings' most prized gadgets but also giving viewers in parts of Central Asia a prime look at the aurora borealis, or northern lights, when darkness falls on Thursday.

"Space weather has gotten very interesting over the past 24 hours," said Joseph Kunches, a space weather scientist with the National Oceanic and Atmospheric Administration (NOAA), on Wednesday.

Meanwhile, NASA warned of a "severe" storm event that would impact both the Earth and Mars as well as some key space agency satellites.

The fuss began late Sunday at an active region on the Sun known as 1429, with a big solar flare that was associated with a burst of solar wind and plasma known as a coronal mass ejection that thrust toward the Earth at some four million miles per hour (6.4 million kilometers per hour).

A pair of solar flares and a CME followed overnight Tuesday-Wednesday, setting off a strong geomagnetic and solar radiation storm registering at level three on a five-step scale.

NASA said the first of the two flares on March 6-7 -- classified in the potent X class and facing directly at the Earth -- was the biggest this year and one of the largest of this cycle known as the solar minimum, which began in early 2007.

In fact, it was second only to a stronger one that erupted in August, and the leading edge of the CME it sparked is expected to reach Earth at 0525 GMT on March 8, plus or minus seven hours.

"Such a CME could result in a severe geomagnetic storm, causing aurora at low latitudes, with possible disruption to high frequency radio communication, global positioning systems (GPS) and power grids," NASA said.

The solar flares alone caused brief high frequency radio blackouts that have now passed, according to NOAA.

The storm is likely "the strongest one since December 2006," Kunches said, noting, however, that the Earth experienced a stronger radio blackout last August.

"But en masse, if you put it all together with the geomagnetic effects and the solar radiation effects, I would put it on par with one at the end of the last solar cycle, which was over five years ago."

Satellites, power grids and even astronauts aboard the International Space Station could be affected by the radiation storm, which may cause them to seek shelter in better protected parts of the orbiting lab as they have in the past.

"Flight surgeons in Houston's mission control center have been monitoring the solar activity and will continue to do so," NASA spokesman Mike Curie said.

"They have determined that there presently is no concern for the six crew members aboard the International Space Station."

However, Kunches said some commercial airlines have already taken actions to reroute and fly further away from the poles.

And more such storms could follow in the coming days because region 1429 is expected to stay active, he said.

Geomagnetic and radiation storms are growing more frequent as the Sun leaves its solar minimum period and moves into a solar maximum over the coming years, but people are generally protected by Earth's magnetic field.

"The current increase in the number of X-class flares is part of the Sun's normal 11-year solar cycle, during which activity on the Sun ramps up to solar maximum, which is expected to peak in late 2013," the US space agency said.

However, some experts are concerned that because the world is more reliant on GPS and satellite technology now than it was during the last solar maximum, more disruptions to modern life are likely.

Space storms are not new. The first major solar flare was recorded by British astronomer Richard Carrington in 1859.

Other solar geomagnetic storms have been observed in recent decades. One huge solar flare in 1972 cut off long-distance telephone communication in the midwestern state of Illinois, NASA said.

Another similar flare in 1989 "provoked geomagnetic storms that disrupted electric power transmission" and caused blackouts across the Canadian province of Quebec, according to the US space agency said. — AFP

source: gmanetwork.com