Our planet has seen a lot of near misses from space rocks

We’ve seen some of the hottest weather of the summer season in Coeur d’Alene. On Tuesday, July 17, Cliff measured a high of 96 degrees. It wasn’t a record, which was 102 degrees in 1918. More very warm to hot weather is expected into early August, but it now looks like we’ll be staying dry with more 90-degree temperatures this week. There could be, however, a passing shower near the higher mountains next week.

Weather patterns in the West have been dominated by a very strong ridge of high pressure. This large dome of air has been so strong that the interior portions of California, the desert southwest and other parts of the West have been experiencing 100-degree heat for days on end. Despite more dry weather, there are indications that we may start seeing an increased chance of showers and perhaps a few thunderstorms toward the middle of August.

If we don’t receive another drop of rain this month, we’ll only have a puny 0.04 inches of moisture for July of 2018. The extremely dry conditions are helping to fuel wildfires across the Pacific Northwest, including one near The Dalles, Ore., last week that closed a portion of Highway 97, and another near Vantage, Wash., that closed I-90. Last year, Cliff measured 0.05 inches in July. But, we do expect to flip to the above-normal side of the precipitation scale later in the fall. Cliff is predicting another 18 inches of moisture between September and the end of December.

Earlier this month, I wrote a column about the number of satellites orbiting the Earth that provide invaluable weather and other types of data. Obviously, satellites orbit the Earth in space, but with all the things going on in our lives, we hardly ever wonder about the constant threats of space rocks, meteors and asteroids that may eventually threaten our planet. An asteroid is a large rocky body in space while a meteorite is a much smaller rock that orbits the sun.

According to NASA, each day our planet is hit with more than 100 tons of dust and sand-sized particles. Scientists estimate that between 18,000 and 84,000 meteorites strike the Earth each year, but most are so small that they will burn up in our atmosphere. However, about once a year, an asteroid the size of an automobile comes into contact with the Earth’s atmosphere and usually burns up due to the friction with the atmosphere that many call “shooting stars.” Approximately every 2,000 years, one of those big space rocks the size of a football field, called a meteoroid, collides with the Earth’s atmosphere.

Approximately 65 million years ago, geologic evidence points to the extinction of the dinosaurs due, at least in part, to a massive impact. A huge rock from space is supported by a layer of metal found around the world, including the oceans, called iridium that dates back about 65 million years. This metal is rare, and it’s primarily found in meteorites and the Earth’s core. Scientists also found a 110-mile crater at Mexico’s Yucatan Peninsula that also matches the date of extinction.

Other evidence also suggest that massive volcanic eruptions may have been responsible for the demise of the dinosaurs. They believe that large volcanic flows originated from India and piled up more than 1.5 miles thick over 1 million square miles.

Over the years, there have been numerous “close calls” of these giant rocks nearly hitting the Earth. Since 1910, there have been at least 52 larger asteroids that have passed within one lunar distance, nearly 250,000 miles. There are likely to be plenty more within the next 100 years, but the chances of one doing significant damage are extremely small.

The most recent close call with an asteroid occurred on April 15. The rock was the size of a football field, between 157 and 361 feet in diameter. It passed about half the distance between the Earth and the moon, nearly 120,000 miles. On Oct. 19, 2017, an asteroid the size of a school bus came too close for comfort and passed between our planet and the moon around 119,000 miles from the Earth’s surface.

In February of 2015, one large rock exploded over Russia and set a record for the most people injured by a meteorite. Scientists believed that the meteorite was about the size of a car and the explosion sent a shockwave strong enough to blow out windows. Fortunately, the meteor didn’t hit anyone, but the damage was about $33 million.

One of the most famous events relating to a meteoroid was the Tunguska event on June 30, 1908, in Siberia, Russia. It was classified as an impact event, the largest in recent recorded history, although no craters were ever found. The Tunguska explosion knocked down an amazing 80 million trees over 830 square miles.

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Contact Randy Mann at randy@longrangeweather.com.