They trained 12 telescopes at 10 different laboratories on the spot, and were able to measure numerous physical characteristics of the little-known planet discovered in 2004.
Until now, ring-like structures had only been found around the four outer planets - Jupiter, Saturn, Uranus and Neptune.
They say the dwarf planet has an unusual elongated ellipsoid shape, with axes of approximately 2,322 kilometres (1,442 miles) by 1,704 kilometres (1,059 miles) by 1,138 kilometres (707 miles), and no global atmosphere that can be detected.
Haumea is twice as long, maybe longer, in one direction as it is in the other, giving it an appearance sort of like a river rock.
The researchers also discovered the ring's orbital period is three times Haumea's spin period which - at less than four hours - is one of the quickest known.
Planetary rings capture the imagination with their stark beauty.
The discovery of a ring around Haumea was unexpected.
"Here we report observations from multiple Earth-based observatories of Haumea passing in front of a distant star". It is the fastest-spinning large object in the solar system, Space.com said.
Like their mythological counterparts centaurs are hybrids - embodying traits of both asteroids and comets.
They also calculated its longest axis is at least 1,430 miles (2,300 km) which is larger than earlier estimates.
The occultation also provided the team with our best analysis yet of Haumea's size and shape, which the researchers describe as "very exotic".
The entire surface of Hi'iaka, one of Haumea's two moons along with Namaka, is also covered in this icy shell.
It is named after the Hawaiian goddess of fertility and childbirth.
The findings were published Wednesday in the journal Nature. Neither of those questions can be answered right now, but if a tiny piece of rock like Haumea can have a decent system of rings, it means that rings might be much more common than we thought.