“Weather radar detects hail and rain,” said Philip Heck, lead research professor at the Field Museum in Chicago and an associate professor at the University of Chicago. “These pieces of the meteorite fell in that range, so the weather radar helped show the position and speed of the meteorite. That means we were able to find it very quickly.”
Elements in the earth, including liquid water, will change a meteorite’s chemical makeup before it can even be collected.
But the Hamburg meteorite – which was collected within two days of falling to Earth – is a prime example of a largely unaltered meteorite.
Meteorite hunter Robert Ward discovered the first part of a meteorite sitting on the frozen surface of Strawberry Lake near Hamburg, Michigan. Ward and private collector Terry Boud donated the Trucks spacecraft to the Field Museum so it could be read.
“This meteorite was special because it crashed into a frozen lake and was quickly recovered. It was so beautiful. We were able to see that not much of the minerals had been changed, and then we found that it contained cargo full of extraterrestrial organic compounds,” Heck said. “These types of organic compounds may have been provided by meteorites early on and may have contributed to life’s material.”
The study was published in the journal Meteorology and Planetary Science on Tuesday.
“When the meteorite arrived at the field, I analyzed it over the entire weekend because I was so excited to find out what kind of meteorite it was and what it contained,” said Jennica Greer, research associate and doctoral student at the University of Chicago, in a statement.
“With every meteorite that falls, there is a chance that something completely new and completely unexpected will happen.”
Here is what they learned.
Commemorative gift from space
The Hamburg meteorite is mostly beautiful because it was collected very quickly after it fell to Earth. This means that it does not take long for the meteorite to become atmospheric, for its metals to begin to rust, for water to escape through cracks and contaminate it, or for its minerals (such as olive) to be replaced.
This quick recovery of the meteorite makes it “significant,” Heck told CNN in an email. And the turmoil around the meteorite led to a well-researched and analyzed study by researchers from 24 different companies.
Scientists believe the Hamburg meteorite traveled through space until it was ejected from its parent asteroid about 12 million years ago and landed on Earth. Analysis of the meteorite revealed that the rock had been exposed to cosmic rays while zipping in space for 12 million years.
Heck said the meteorite came from an asteroid that formed 4.5 billion years ago, about 20 million years after our solar system formed.
It produced 2,600 different organic compounds, including the Hamburg meteorite Parent Asteroid.
It is called H4chondrite, which is a type of meteorite that is not known to be rich in organisms.
“This meteorite shows a high diversity of creatures, and if anyone is interested in studying the creatures in it, this is not the type of meteorite they usually ask to see,” Greer said. “But there was so much excitement around it that everyone wanted to use their own technique for it, so we have an unusually comprehensive database for a meteorite.”
In general, carbonaceous chondrites are thousands of times richer than H4 chondrites, Heck said. NASA’s Osiris-Rex mission recently modeled near-Earth asteroid Pennu on carbon.
“The fact that this normal contradictory meteorite is full of organisms supports the hypothesis that meteorites played an important role in the early delivery of organic compounds on Earth,” Heck said. “Throughout Earth’s history meteorites have fallen on our planet, providing some building blocks for life on Earth, even before life formed.”
The organic matter in the meteorite was first heated up to 1,200 degrees Fahrenheit, which was part of its parent asteroid. This actually reduced the diversity of organic compounds in the meteorite from a million to two thousand. But despite the heat-induced changes, Heck was still amazed at how many organic compounds were in the meteorite.
The researchers found hydrocarbons and compounds containing sulfur and nitrogen.
“Much more work needs to be done to better understand the individual chemical pathways of different compounds and the different processes by which organic matter goes,” Heck said.
The Hamburg meteorite can be compared to other models collected in the future – including the original models recovered from asteroids by the Japan Space Research Organization’s Hayabusa 2 mission and NASA’s Osiris-Rex mission. The first model of the asteroid Ryu will be delivered to Earth by Hayabusa 2 in December, while the model from Pennu will return in 2023.
“But we’re also looking at new meteor waterfalls,” Heck said. “Every meteorite that falls to Earth is worth studying because it can give a unique view of the solar system and shed new light on its history and our origins.”