A large comet spanning 3-5 km in width, large enough to have severe consequences if it had crash landed on Earth’s surface. Theorists hypothesized that it would be similar to the events that led to the extinction of dinosaurs 65 million years ago. These events may include unnatural drop in Earth’s atmospheric temperature, nuclear winters, and decreased sunlight.
A comet is made of rock, ice, dust, and organic compounds and can be several kilometers long in diameter. However, comets are fragile and can be broken into smaller pieces fairly easily. NASA noted that comet Elenin flew within 75 million kilometers of the sun and broke apart. As the comet approached Earth, it was only a cloud of debris, only visible through a telescope.
Don Yeomans of NASA’s Near-Earth Object Program says that the comet won’t be back for another 12,000 years. He noted that there has been hype on the internet about the comet and the consequences of it entering Earth. Yeomans said that in scientific reality, the comet is incredibly miniscule to have any impact on Earth’s gravitational pull to affect any environmental changes on Earth. The comet passed Earth at a distance that is ninety times the distance of the moon, and its mass was one-hundredths the size of the moon. If anything, the moon is currently exerting significantly more environmental changes than Elenin.
Maybe this event was nothing we should’ve been scared about in the first place. Only time will tell if the next space matter heading towards Earth is large enough for the hypothesized phenomena that were attributed to this comet.
Comet Elenin heads towards Earth
Further Reading:
http://thewatchers.adorraeli.com/2011/10/25/remains-of-comet-elenin-maybe-spotted/
http://www.jpl.nasa.gov/news/news.cfm?release=2011-135