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NASA: Earth’s Ozone Hole Shrinks to Smallest Since 1988

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NASA: Earth's Ozone Hole Shrinks to Smallest Since 1988 (VOA)

Washington: The ozone hole over Antarctica shrank to its smallest peak since 1988, NASA said Thursday. The huge hole in Earth’s protective ozone layer reached its maximum this year in September, and this year NASA said it was 7.6 million square miles (19.6 million square kilometers). The hole size shrinks after mid-September.

This year’s maximum hole is more than twice as big as the United States, but it’s 1.3 million square miles smaller than last year and 3.3 million square miles smaller than 2015.

FILE - A false-color view of total ozone over the Antarctic pole is seen in this NASA handout image released Oct. 24, 2012. The purple and blue colors are where there is the least ozone. The average area covered by the Antarctic ozone hole in that year was the second smallest in two decades, at 8.2 million square miles; in September 2017, it was 7.6 million square miles.

[ FILE – A false-color view of total ozone over the Antarctic pole is seen in this NASA handout image released Oct. 24, 2012. The purple and blue colors are where there is the least ozone. The average area covered by the Antarctic ozone hole in that year was the second smallest in two decades, at 8.2 million square miles; in September 2017, it was 7.6 million square miles ].

Paul Newman, chief Earth scientist at NASA’s Goddard Space Flight Center, said stormy conditions in the upper atmosphere warmed the air and kept the chemicals chlorine and bromine from eating ozone. He said scientists haven’t quite figured out why some years are stormier — and have smaller ozone holes — than others.

“It’s really small this year. That’s a good thing,” Newman said.

Newman said this year’s drop is mostly natural but is on top of a trend of smaller steady improvements likely from the banning of ozone-eating chemicals in a 1987 international treaty. The ozone hole hit its highest in 2000 at 11.5 million square miles (29.86 million square kilometers).

Ozone is a colorless combination of three oxygen atoms. High in the atmosphere, about 7 to 25 miles (11 to 40 kilometers) above the Earth, ozone shields Earth from ultraviolet rays that cause skin cancer, crop damage and other problems.

Scientists at the United Nations a few years ago determined that without the 1987 treaty, by 2030 there would have been an extra 2 million skin cancer cases. They said that overall, the ozone layer is beginning to recover because of the phase-out of chemicals used in refrigerants and aerosol cans. (VOA)

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Incredible Full Moon Falls on 50th Anniversary of NASA’s Apollo 11

The partial lunar eclipse will occur during the full moon beginning Tuesday night

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Full Moon, Anniversary, NASA
The moon is seen during a lunar eclipse known as the "Super Blood Wolf Moon," in Manaus, Brazil, Jan. 21, 2019. VOA

The last lunar eclipse of the year will take place this week, allowing stargazers from large swathes of the globe to catch a glimpse of the celestial phenomena.

The partial lunar eclipse will occur during the full moon beginning Tuesday night, and will be visible in South America, Europe, Africa, Asia and Australia. The only region that will miss out on viewing the eclipse entirely is North America.

A lunar eclipse occurs when there is an alignment of the moon, the sun and the Earth. It can only happen during a full moon, because that is the only time the moon can be directly opposite of the sun in Earth’s sky.

The upcoming alignment will result in a partial lunar eclipse because the moon will be slightly askew from a direct line with Earth’s shadow.

Full Moon, Anniversary, NASA
The last lunar eclipse of the year will take place this week, allowing stargazers from large swathes of the globe to catch a glimpse of the celestial phenomena. Pixabay

This lunar eclipse will come two weeks after a total eclipse of the sun was visible over South America. This follows a typical astronomical pattern of lunar eclipses occurring within two weeks of a solar eclipse.

The last lunar eclipse took place in January 2019 and was visible from both Americas as well as parts of Europe and Africa. The next lunar eclipse will not take place until next year, however all four eclipses in 2020 will only be penumbral eclipses, which are much weaker than partial or full eclipses.

During penumbral eclipses, the moon passes through the weakest shadow cast by Earth and often does not visibly darken to the naked eye.

There won’t be another total lunar eclipse until May 2021.

Also Read- India Aborts Launch of Spacecraft Intended to Land on Far Side of Moon

Apollo anniversary

Tuesday’s lunar eclipse will be seen by stargazers at different times around the globe. Viewers in South America will be the first to see Earth’s shadow touch the moon’s surface when the moon is rising in the sky around sunset July 16, while watchers in Asia and Australia will see the moon in eclipse as it sets around sunrise July 17.

Interestingly, this celestial event falls on the anniversary of another lunar happening: July 16 is the 50th anniversary of the Apollo 11 rocket launch, which first landed humans on the moon. (VOA)