Questão 3170438

Comet Fragment Explodes in Dark Skies Over Spain and Portugal

1. At 11:46 p.m. in Portugal, .... fireball streaked across the sky, leaving .... smoldering trail
2. of incandescent graffiti in its wake. Footage shared on social media shows jaws dropping as the
3. dark night briefly turns into day, blazing in shades of snowy white, otherworldly green, and arctic
4. blue. Rocky asteroids cause sky-high streaks as they self-destruct in Earth’s atmosphere with
5. some frequency. But over the weekend, .... projectile was plunging toward Earth at ....
6. remarkable speed — around 100,000 miles per hour, more than twice that expected by a typical
7. asteroid. Experts say it had a strange trajectory, not matching the sort normally taken by nearby
8. space rocks.
9. That’s because it wasn’t an asteroid. It was a fragment of a comet — an icy object that may
10. have formed at the dawn of the solar system — that lost its battle with our planet’s atmosphere
11. 37 miles above the Atlantic Ocean. No parts of the object is likely to have made it to the ground,
12. the European Space Agency said. “It’s an unexpected interplanetary fireworks show”, said Meg
13. Schwamb, a planetary astronomer at Queen’s University Belfast. It is not rare for comets to
14. create shooting stars. “We have notable meteor showers throughout the year, which are the
15. result of the Earth crossing debris clouds of specific comets”, Dr. Schwamb said.
16. These meteor showers, and the lone shard over the weekend, light up the sky in a similar
17. manner. Air in front of the objects is compressed and heats up, which cooks, erodes, cracks
18. open, and obliterates the debris. That destructive process releases light — and, if the projectile
19. is big enough, a powerful shock wave when it surrenders its immense kinetic energy into the
20. sky. The weekend’s “chunk is likely a bit bigger than a good fraction of the meteors we see during
21. meteor showers, so this just made a bigger light show”, Dr. Schwamb said. In addition to its
22. flashy performance, the comet fragment’s breakup served as a dry run for experts hoping to
23. defend the planet from large killer asteroids.
24. One tenet of planetary defense is to find space rocks before they find us; that way, the
25. planet’s protectors can try to do something about them. But the shard over Portugal and Spain
26. was not spied on before its demise. “It would have been great to detect the object prior to
27. colliding with the Earth”, said Juan Luis Cano, a member of the Planetary Defence Office at the
28. European Space Agency. The worry is that an object just a little larger than Saturday’s missile
29. could again escape detection and explode with lethal effect over an unaware, unwarned city. The
30. meager, 55-foot meteor that exploded above the Russian city of Chelyabinsk in 2013, for
31. example, wasn’t identified before its arrival, either — and its airborne blast, equivalent to nearly
32. 500,000 tons of TNT, caused widespread damage, which injured at least 1,200 people.
33. But with improved technology on the ground and in space, the hope is that even tiny,
34. harmless objects from around the solar system (like the weekend’s icy visitor, which experts
35. estimate was a few feet across) can be spotted, providing practice for planetary defense
36. researchers searching the heavens for the common but elusive football-field-size rocks that could
37. destroy a city. Fortunately, a series of next-generation observatories are set to come online in
38. the next few years — including one named after an American astronomer, the Vera C. Rubin
39. Observatory in Chile, which will spot millions of faint and previously undiscovered asteroids. For
40. now, the spectacle in Spain and Portugal reminds us that Earth is a participant in the solar
41. system’s never-ending game of planetary billiards, and that working to find as many killer space
42. rocks as possible is a task of the utmost importance.

(Available at: www.nytimes.com/2024/05/19/science/comet-fireball-portugal-spain.html – text specially adapted for this test).

The excerpt “It would have been great to detect the object” (l. 26) expresses: