This article was originally published on The conversation. The publication contributed the article to Space.com’s Expert Voices: Op-Ed & Insights.
Monica Grady, Professor of Planetary and Space Sciences, Open University
While people in the UK were watching the late night news on 28 February, a fresh news report appeared, literally in the night sky. A large and very bright fireball was spotted over southern England and northern France at 21:54 GMT. It was captured by many doorbell cameras, so it was a very well-observed fireball. More importantly, it is also captured by the UK Meteor Observation Network’s automated cameras and similar networks.
In collaboration with colleagues in France and Australia, the meteorite viewers worked out the trajectory of the fireball and determined where the meteorite pieces could be just north of Cheltenham in the UK. Based on their calculations, Ashley King, a meteorite specialist at the Natural History Museum in London, called on local TV and radio stations for information on any unusual black rocks that fell from the sky.
Related: Meteorite of brilliant British fireball is the first England in 30 years
Among the photographs he received, there was one that caught his attention: a small pile of dust and pebbles on a driveway in the small town of Winchcombe. King asked Open University researcher Richard Greenwood (who lived closest) to investigate the example. Greenwood was overwhelmed to discover that it was not only a meteorite, but also a very rare species. The UK was lucky – we had a new member to add to our meteorite collection.
Over the next four days, specialist researchers from various British institutions assembled teams to systematically search the Winchcombe rural area. The results of their labor are several stones weighing about 500 g, plus lots of dust and fragments. The specimens are now in the Natural History Museum.
Precious rocks
Why is this such a big deal? Meteorites are divided into two main groups: primitive and processed. The primitive comes from the solar nebula that gave birth to the solar system, which retains the composition of this original material. In contrast, processed samples were altered by heat. It comes from larger bodies and contains information on planetary surfaces and interiors.
The rocks that fell over Winchcombe are of the former group – and not only, they are of a subcategory known as carbonaceous chondrites – the pristine (or unchanged) of all meteorites, containing records of the earliest phases of the solar system. history. They are rich in organic compounds: the molecules that form the building blocks of life. It also contains small dust species of stars that are dead and older than the sun.
Some of the newly found rocks are almost entirely black and distinctive, while others are dark gray with irregular, pale spots. It is clear that it is a complex meteorite, possibly one originating from the surface of an asteroid, where several pieces of asteroid collided during collisions.
And this is where things get a little ironic: scientists are currently collecting samples of two asteroids in space. About five grams of material collected by the Japanese Hayabusa2 mission from the asteroid Ryugu arrived safely in December 2020. Nasa’s OSIRIS-Rex mission is on its return journey from the asteroid Bennu with about 200 g of material that will arrive in September 2023. These missions cost a lot of money, but can help reveal the secrets of the origin of life and the solar system. And then just fall out of nowhere, almost 500g of rock from an asteroid, possibly very similar to Ryugu and Bennu, over part of England.
Next steps
Meteorologists in the UK will now be practically analyzing the material on a grain-by-grain basis. Things have to happen in a row – there are time-sensitive measurements that need to be done within the first month or so of a new fall. Meteorites are not radioactive – they do not emit harmful radiation – but contain elements that are unstable and fall apart. And if we can measure the quantities of the elements that decay quickly, we can get valuable information.
We must also take a good look at the organic compounds in the meteorite – there is always a danger of pollution from the earth. So, the faster we can analyze its organic organisms, the better. The more we can understand some of these materials in meteorites, the more we can compose the chemistry that led to life on earth. It can give an idea of how widespread the chemistry is (or was) in the solar system (or even in the universe).
The search for a meteorite in a small town and its surrounding fields is usually not dangerous and requires little risk assessment: ask permission from the owners to gain access to their land, keep the land code in mind, remember to lock gates and do not step into anything soft. But in the time of a pandemic, everything changes.
The British government currently prohibits citizens from traveling far from home unless it is necessary. Was it necessary for a group of meteorites to travel to Winchcombe? Yes, it was. Each completed the risk assessments in the field and obtained permission to travel from their institutions. They were meticulous about wearing masks and keeping a distance of 2 meters when talking to locals.
I would love to be involved in the search – although my colleague Sara Russell told me that cleaning the owner’s driveway with a toothbrush faded after the first hour. My arthritic knees would not be able to handle it. But I was on base again and did something just as important: get machinery up and running to get Greenwood’s paper review sorted out for Greenwood. And as a reward, I saw the first photos of our new family member, named ‘Winchcombe’. It may look a bit like a broken barbecue briquette, but to me it’s absolutely beautiful.
This article was published from The Conversation under a Creative Commons license. Read the original article.
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