- 3568 - ASTEROIDS - here are the close flybys? An asteroid that swept by Earth in 1989 will be coming back around for a much closer visit at the end of May, 2022. “Asteroid 1989 JA” was discovered on May 1, 1989. It came close to Earth but was not considered hazardous at the time.
--------------------- 3568 - ASTEROIDS - here are the close flybys?
- This time Asteroid 1989 JA will be close enough to be considered potentially hazardous, and even be visible with a small telescope from Earth. It will still be about 2.5 million miles away from Earth when it swings by on May 27,2022.
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- The large space rock will also cross over Earth’s orbital path passing behind our planet as it continues its journey around the Sun. It has a 861-day orbit around the Sun. That causes the asteroid to return to Earth’s neighborhood at irregular intervals, sometimes a few years apart, other times a couple decades. The asteroid coming within 2.5 million miles of Earth is around 10 times the distance to the moon from Earth.
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- The previous closest encounter with the asteroid was 3.4 million miles in 1949. May’s encounter with the asteroid will be the closest approach for at least the next two centuries.
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- Due to the fact that 1989 JA will cross Earth’s orbit and take longer than an Earth year to orbit the sun (861 years), it is classified as an “Apollo asteroid“.
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- “Asteroid 1989 JA” might not be a major cause for concern, yet it still is categorized as a potentially hazardous asteroid. Scientists refer to asteroids as potentially hazardous when they travel within 4.6 million miles or less and are larger than 500 feet in diameter.
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- An object that size has the potential to cause great damage to our planet. If an object is much smaller and happens to encounter Earth, it will mostly burn up in the atmosphere and cause no major threat.
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- There is not a high threat to the planet until 2186, when “asteroid 2009 FD” will pass by. Even though significant, the chance of impact is still only 0.2 percent.
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- The asteroid 1989 JA should slip safely past Earth on its travels around the sun. It is only one of the numerous near-Earth Asteroids (NEA) that NASA and others have been keeping an eye on.
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- A near-Earth object, “Asteroid 2006 FJ42“, estimated to be a diameter of between 380 meters and 860 meters, came within 2.7 million miles of Earth last year.
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- “Asteroid 2022 GN1” also flew safely past Earth last month, coming within 79,000 miles.
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- These passes happen frequently, yet have a low chance of impacting our planet. There are currently more than 870 near-Earth asteroids (NEAs). There are still many to be discovered, with many factors such as visibility and location making it difficult to detect some these asteroids.
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- The largest asteroid scientists have discovered so far is “1036 Ganymed“, which is 25.5 miles in diameter. Luckily, this city-sized asteroid has little chance of approaching Earth in our lifetime.
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- NASA is investigating the “Asteroid Bennu“, which has a slight chance of impacting Earth in the late 2100s. A recent extremely close encounter happened in 2008 when an asteroid came within 4,000 miles of Earth.
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- As for accounts of actual Earth impacts, there is a record of an asteroid or comet 330 feet in diameter breaking apart over remote Siberia in 1908. A 66-foot meteor also exploded over Chelyabinsk, Russia in 2013, causing more than 1,000 injuries.
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- After it safely passes by Earth in May 2022, “Asteroid 1989 JA” will return in the coming years. In 2029 and 2048 the asteroid will fly by much further away, more than 24 million miles. Two more passes will be made, in 2055, and 2062, before 1989 JA comes as close as it was when first discovered. A closer approach will be made again in 2081, when 1989 JA comes within 7 million miles of Earth.
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- NASA’s Lucy mission is set to explore a group of asteroids that follow behind and in front of Jupiter's orbit. This mission will study the crumbs leftover from the early Solar System, and it needs to reach Jupiter’s orbit, where two gravitational crevices have collected them.
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- Operating farther from the Sun requires big solar arrays to capture the diminishing sunlight for energy, so Lucy was equipped with two peeper-like solar wings. Shortly after its October , 2021 launch, NASA officials noticed something was wrong with one of the solar arrays. Its readings were unusual, and personnel soon realized that the lanyard wrapping around one solar array hadn’t fully retracted, blocking some sunlight from reaching the panels.
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- According to NASA officials, the faulty array is between 75 percent and 95 percent deployed. The space agency has been monitoring the situation for the last half-year, and on April 18, 2022, they decided on a plan forward they hope will solve the issue. They will perform two steps over the next several months to see if the solar array can be fully deployed.
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- The first will happen on May 9, when they will attempt to reel back some of the lanyard in a quick maneuver. The team anticipates that this single operation won’t be enough, so they are planning a second array deployment task for a month later, which will hopefully successfully latch the solar array. The month between each task will give the teams time to analyze the best way to perform the second maneuver.
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- The solar array was designed with both a primary and a backup motor winding to give an added layer of reliability for the mission-critical solar array deployment. Lucy engineers will take advantage of this redundancy by using both motors simultaneously to generate higher torque than was used on the day of launch.
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- Ground tests show that this added torque may be enough to pull the snarled lanyard the remaining distance needed to latch. So far, the issue hasn’t affected the mission too severely. That solar array is generating nearly the expected power when compared to the fully deployed wing. This power level is enough to keep the spacecraft healthy and functioning.
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- Having fully charged batteries is important. Lucy is heading out to Jupiter at a speed of roughly 67,000 mph to study the Trojan asteroids, peculiar rocks significantly different from those found between the orbits of Mars and Jupiter in the Asteroid Belt.
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- The Trojans are leftover pieces from the formation of the Solar System that were looped into Jupiter’s orbit and thus avoided being ejected into deep space. The Trojans are trapped in two gravitationally stable spots called “Lagrange Point 4” and “Lagrange Point 5“, created by the gravity interaction of the Sun and Jupiter.
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- Lucy will study seven asteroids over 12 years, so having fully-operating batteries will be critical. Lucy will reach its first target in 2025, an Asteroid Belt object dubbed “Donaldjohanson“.
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- After its encounter with that asteroid, the craft will continue toward the group of Trojans residing in front of Jupiter, targeting a 2027 arrival. After that, a maneuver will bring it back to the inner Solar System to use Earth for a gravity assist in 2031, only to swing back out for a second Trojan trip in 2033 toward the trailing asteroids.
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- The mission is named after the three million-year-old hominid fossil discovered in Ethiopia in 1974. Donaldjohanson is named after Lucy’s discoverer.
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- “Lucy” is both an homage to the science of origins and likely a nod to The Beatles’ song that inspired the fossil’s name, “Lucy in the Sky with Diamonds.”
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May 3, 2022 ASTEROIDS - here are the close flybys? 3568
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