(IME - 2016/2017 - 2ª FASE)
Texto 2
COULD EARTH BE FRIED BY A ‘SUPERFLARE’ FROM THE SUN?
Daniel Clery
Solar flares on the sun frequently shower Earth with high-energy particles causing the Aurora Borealis and, occasionally, less-welcome disruptions to power networks and communications. But researchers say that there is a chance—though small—that the sun could one day blast us with a solar flare thousands of times as powerful, potentially frying our atmosphere and obliterating life. Other stars occasionally produce such “superflares,” some up to 10,000 times the power of the largest solar flare ever detected. To see whether these are generated by the same process as happens on the sun—the breaking and reconnection of magnetic fields—astronomers studied light from 100,000 stars using China’s Guo Shouiing Telescope. As they report online in Nature Communications, superflares do seem to be produced by the same process, but they usually occur in stars with much stronger magnetic fields than the sun’s. Still, the researchers found that about 10% of the superflaring stars had magnetic fields similar to or weaker than the sun’s. From evidence in tree rings, the researchers say, it looks like Earth suffered small superflares—10 to 100 times bigger than normal—in 775 C.E. and 993 C.E. We can expect more, they conclude, once per millennium. (As for the chances of an Earth-frying flare, they don’t say.) So, back up your data and stock up on candles.
*C.E. = Common Era, the same as A.D., Anno Domini.
CLERY, D. Could earth be fried by a ‘superflare’ from the sun?. In: Science, AAAS, 2016. Disponível em: <http://www.sciencemag.org/news/2016/03/could-earth-be-fried-superflare-sun>. Acesso em: 15/06/2016.
Choose the correct option.
An equipment from an Asian country broke and reconnected 100,000 magnetic fields.
10,000 “strong” solar flares produced by other stars were detected.
100,000 stars have stronger magnetic fields than the sun's.
The breaking and reconnection of magnetic fields surely produce superflares from stars different from the sun.
Bigger than normal flares may have reached our planet.
Gabarito:
Bigger than normal flares may have reached our planet.
A alternativa correta é a E) Bigger than normal flares may have reached our planet. (Chamas maiores que o normal podem ter atingido nosso planeta)
As outras alternativas estão incorretas.
A) Um equipamento de um país asiático quebrou e reconectou 100.000 campos magnéticos.
B) 10.000 explosões solares fortes produzidas por outras estrelas foram detectadas.
C) 100.000 estrelas têm campos magnéticos mais fortes que os do sol.
D) A quebra e reconexão de campos magnéticos certamente produzem super explosões de estrelas diferentes do sol.