A few years ago, I got an email from a colleague in Lima, Peru, asking me if I would help identify a recently discovered meteorite. I was intrigued and happy to assist.

The meteorite was found in a remote region of the Puno region of Peru, near Lake Titicaca. The locals who found the meteorite called it "Huaytapallana" after the nearby mountain.

The meteorite was a large elliptical mass of extraterrestrial rock that weighed over two tonnes (4,000 pounds) making it one of the largest meteorites ever found. It was classified as a pallasite, a rare type of meteorite that contains large, spherical crystals of olivine within a matrix of silicate minerals.

Where might the meteorite come from?

To determine where the meteorite came from, we began by studying the mineralogy and chemical composition of the meteorite. We also measured the meteorite's magnetic susceptibility and remanence, which gives information about the meteorite's past thermal and magnetic history.

We also worked with colleagues in Peru to conduct a detailed petrographic study of the meteorite, which involved making thin sections and examining the meteorite under a microscope. We also performed X-ray diffraction analysis and geochemical analysis to determine the meteorite's mineral composition and major elements.

Based on these analyses, we believe the meteorite originated from a Vesta, a large main-belt asteroid that is the second most massive object in the asteroid belt. Vesta is a very ancient object, with a surface that has many old impact craters and volcanic features.

We believe that the Huaytapallana meteorite was ejected from Vesta by a giant impact event that occurred some time in the past. The meteorite then traveled through the solar system for millions of years before eventually encountering Earth's gravitational field and being pulled down to our planet.

The meteorite entered the Earth's atmosphere at a very high speed and was heated to more than 1,500 degrees Celsius (2,700 degrees Fahrenheit). The intense heat created a molten outer layer that caused the meteorite to ablate, or break up into smaller pieces.

The smaller pieces of the meteorite fell through the atmosphere and landed in a wide area around Lake Titicaca, with the largest pieces landing near the town of Puno.

The Huaytapallana meteorite is a fascinating object that has provided us with a glimpse into the early solar system where large impacts and asteroidal collisions were shaping planets. It is also a reminder of the importance of studying meteorites to learn more about the origins of our own planet and the solar system.