Why being hit by space dust is an unavoidable aspect of space travel

On 8 June, NASA revealed that its new powerful space observatory, James Web Space Telescope, is now playing a small dimple in one of its primary mirrors, which is in deep space by a large-to-first micrometer. After exiting. The news came as a shock since the telescope’s space tenure just five months into effect – but such attacks are an essential aspect of space travel, and there are certainly more attacks on their way.

Despite the meaning of its name, the location is not vacant at all. Within our solar system, tiny bits of space dust are zooming into the regions between our planets at speeds that can reach thousands of miles per hour. These microscopic meteorites, which are no larger than a grain of sand, are often small fragments of asteroids or comets that have broken up and are now orbiting the Sun. And they are everywhere. A rough estimate of small meteorites in the inner Solar System puts their combined total mass at about 55 trillion tons (if they were all combined into one rock, it would be about the size of a small island).

This means that if you send a spacecraft into deep space, your hardware will almost certainly get hit by one of these tiny pieces of space rock at some point. Knowing this, spacecraft engineers would build their vehicles with certain protections to avoid micrometeoroid attacks. They often include something called a special multi-layer barrier called Whipple shielding. If the gradient hits a micrometer, the particle will pass through the first layer and slice further, so the second layer collides with even smaller particles. इस तरह के परिरक्षण का उपयोग आमतौर पर अतिरिक्त सुरक्षा के लिए अंतरिक्ष यान के संवेदनशील घटकों के आसपास किया जाता है।

But with NASA’s James Webb Space Telescope, or JWST, it’s more difficult. The telescope’s gold-coated mirrors must be exposed to the space environment in order to properly collect light from the distant universe. And while these mirrors were built to withstand some impacts, they are more or less the sitting duck for larger micrometeoroid attacks, like the one that struck JWST in May. Although the micrometer was still smaller than a grain of sand, it was larger than NASA estimated—enough to damage a mirror.

The spacecraft operators form a model of micrometer population in space to better understand how often the spacecraft can be hit in any part of the solar system – and which size particles can destroy their hardware. But still, it is not a foolproof system. “It’s all likely,” tells David Malaspina, an astrophysicist at the University of Colorado, focusing on the effects of cosmic dust on spacecraft. ledge, “You can only say, ‘I have a good chance of being hit by a particle of this size.’ But whether you ever do this or not, it depends on the coincidence. “

Image: NASA

Micrometeoroids has a wide range of origin stories. वे अंतरिक्ष में उच्च गति की टक्करों के बचे हुए उत्पाद हो सकते हैं, जो अंतरिक्ष चट्टानों को छोटे टुकड़ों में चूर-चूर कर देते हैं। क्षुद्रग्रह और धूमकेतु भी समय के साथ सूर्य से अंतरिक्ष कणों और फोटॉनों द्वारा बमबारी करते हैं, जिससे छोटे टुकड़े टूट जाते हैं। An asteroid can also get very close to a large planet like Jupiter, where the strong gravitational pull breaks up pieces of rock. या कोई वस्तु सूर्य के बहुत करीब आ सकती है और बहुत गर्म हो सकती है, जिससे चट्टान का विस्तार हो सकता है और टुकड़े-टुकड़े हो सकते हैं। यहां तक ​​​​कि इंटरस्टेलर माइक्रोमीटरोइड्स भी हैं जो हमारे सौर मंडल से अधिक दूर के ब्रह्मांडीय पड़ोस से गुजर रहे हैं।

How fast these particles move depends on which region of space they are in and the path they travel around our star, averaging about 45,000 miles per hour, or 20 kilometers per second. Whether or not they will run in your spaceship also depends on where your vehicle lives in space and how fast it is moving. For example, NASA’s Parker Solar Probe is currently the closest man-made object to the Sun, moving at a top speed of more than 400,000 mph. “It goes down to the 4-yard line compared to being at one end of Earth,” says Malaspina, who focuses on studying micrometeoroid effects on the Parker Solar Probe. It is also passing through the densest part of a region called the zodiacal cloud, a thick disk of space particles that enters our solar system. So Parker Solar Probe is getting sandblasted more often than JWST—and it’s hitting these particles at incredibly high speeds, as the telescope will hit.

Parker Solar Probe is giving us a better understanding of the micrometeoroids around the Sun, लेकिन हमें पृथ्वी के आसपास की आबादी के बारे में भी अच्छी समझ है। Whenever a micrometer hits our planet’s upper atmosphere, it burns up and creates meteorite smoke – fine smoke particles that can be measured. The amount of this smoke can tell us how much dust is hitting Earth over time. Additionally, experiments have been conducted on the International Space Station, where materials have been placed outside the orbital laboratory to see how often they are bombarded.

Image: NASA

While JWST remains at a distance of about 1 million miles from Earth, it is still relatively close. Scientists also have an idea of ​​what’s out there based on other missions sent to the same orbit as JWST. और अधिकांश सामान जो दूरबीन से टकराता है वह इतना बड़ा सौदा नहीं है। “Spacecraft get hit by the little ones all the time,” Malaspina says. “By little, I mean fractions of a micron—much, much smaller than a human hair. And for the most part, the spacecraft doesn’t even notice them.” In fact, the JWST may have larger micrometers. He had been hit by the tiny micrometer four times before he was caught.

NASA had prepared a model of the micrometer atmosphere before the launch of JWST, but in the light of the recent effect, the agency can improve its model and better estimate what could happen to the telescope after future effects. A new team has been called. Current micrometeoroid modeling will try to predict things such as how debris propagates through orbit when an asteroid or comet separates. That kind of debris is more mobile, Malaspina says, which makes it harder to predict.

At the end of the day, though, the prediction will tell you more about when A spacecraft can be hit by a large particle of dust. Such outright effects are simply inevitable. JWST would continue to dissipate over time, but it was an event NASA was always prepared for. “You just have to live with the possibility that you’ll eventually hit a dust particle of some size, and that’s the best you can do with engineering,” Malaspina says.