I can't say that I've ever heard of the Jovian Trojans before. It sounds like some sort of high school football team, but the name actually refers to asteroids that circle the sun in the same orbit as Jupiter. Scientists have been studying these asteroids using data generated by NASA's Wide-field Infrared Explorer or WISE. NASA says that the Jovian Trojans travel in packs with one group of asteroids ahead of Jupiter and the other group behind Jupiter.
The observations made using WISE are the first that have offered a detailed look at the color of the Trojans in the leading and trailing packs. The data determined that the Jovian Trojans are made up predominantly of dark, reddish rocks with a matte, non-reflective surface. The observations also allowed astronomers to confirm previous suspicions that the leading pack of Jovian Trojans was larger than the trailing pack.
The scientists are trying to determine more than simply what the asteroids look like, they want to know where the asteroids came from. WISE data shows that the asteroids are strikingly similar with no interlopers from other parts of the solar system. The Jovian Trojans also don't resemble asteroids from the main asteroid belt between Mars and Jupiter.
The scientists say that the Jovian Trojans don't resemble asteroids from the Kuiper belt family of objects near Pluto either. The first Jovian Trojan was discovered in February 22, 1906 by German astronomer named Max Wolf. This particular Trojan was called Achilles and is roughly 220 miles wide. The scientists are still unsure exactly how many asteroids are included in the two packs of Jovian Trojans, but they believe there are as many objects in the two packs as there are in the entirety of the main asteroid belt between Mars and Jupiter. The scientists have proposed future space mission to study the Jovian Trojans and gather data needed to determine how old they are and where the asteroids came from.