NASA's Mercury-orbiting spacecraft, Messenger, has crashed onto Mercury, ending its four-year mission.

The spacecraft launched more than a decade ago from Florida's Space Coast on a mission to study Mercury.

MESSENGER stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging. NASA has gotten some extra years out of the spacecraft, but it finally ran out of fuel, and so the space agency decided to end the mission with a bang.

Messenger launched in 2004 from Cape Canaveral Air Force Station. It only arrived at Mercury and began to orbit the planet in 2011 — becoming the first spacecraft to circle the planet.

Over the last four-plus years, Messenger has studied the most hostile planet, where temperatures range from 800 degrees during the day to minus 290 degrees at night.

The spacecraft has led to scientific discoveries about the small, airless planet.

"We confirmed with each test the planet closest to the sun indeed harbors water-ice at both poles," said Sean Solomon, Messenger's principal investigator.

Thanks to Messenger, NASA has learned more about the planet's makeup, its bizarrely offset magnetic field and evidence that Mercury may have shrunk.

Scientists said Messenger is helping tell the story of how the solar system was formed.

"It's really the beginning chapters rather than the later chapters," Solomon said. "It's the chapters about the delivery of the building blocks for life, which are extraordinarily well preserved on Mercury."

Messenger plunged from orbit at a speed of more than 8,750 mph and carved out a crater estimated to be 52 feet in diameter.

NASA got confirmation about 14 minutes after it happened.

The next spacecraft to study Mercury won't arrive at the planet until the 2020s. In the meantime, scientists will be combing over the data from Messenger.

A look at Mercury's soon-to-be-obliterated travel companion:

ROUNDABOUT FLIGHT

Messenger rocketed away from Cape Canaveral, Florida, in August 2004. It flew twice past Venus and three times past Mercury, before entering orbit around Mercury in March 2011. Only one other spacecraft, NASA's Mariner 10, has ever visited Mercury, and that was back in the 1970s. Mariner 10 flew past, but did not orbit the innermost planet. The $427 million Messenger mission was developed and run for NASA by Johns Hopkins University.

SCIENCE DISCOVERIES

During its four years in orbit - comprising more than 4,000 laps - Messenger has revealed volcanic deposits at Mercury that are helping to explain the planet's important eruptive and interior-melting past; polar caps of frozen water at or near the surface; and incredible global shrinkage thanks to a cooling interior. In addition, despite its proximity to the sun, Mercury is more abundant in volatile elements, like potassium and sulfur, than anticipated before Messenger's arrival, according to Messenger's principal investigator Sean Solomon, director of Columbia University's Lamont-Doherty Earth Observatory. Planetary scientists will be looking at Messenger's huge stash of data "for years, probably for decades, as we try to understand the origin and evolution of Mercury," Solomon said.

SUPER SUNSHADE

Messenger's creators needed to keep the spacecraft cool during its super-hot mission at Mercury. "It's an enormously hostile environment," said Jim Green, director of planetary science for NASA. Designers came up with a novel sunshade of lightweight ceramic cloth. This sunscreen tolerated more than 600 degrees Fahrenheit (316 degrees Celsius) on the front, while keeping everything behind it at room temperature, including the seven scientific instruments. Messenger also regularly performed "an intricate dance" to balance all the infrared heat that was reflected off Mercury back at the spacecraft. At the same time, engineers equipped Messenger with numerous heaters to keep the fuel from freezing and the electronics from faltering when the spacecraft ducked behind the planet, away from the sun.

SMASHING END

On Thursday, Messenger is expected to crash into the side of Mercury facing away from Earth. So there will be no cameras or observatories to witness the impact. Scientists expect to gather information from Messenger until 10 to 15 minutes before its fatal plunge. The expected crash site is about two-thirds of the way up the planet, near the north pole. Mercury is the smallest planet - a little bigger than our moon.

UPCOMING AT MERCURY:

A pair of European and Japanese spacecraft will aim for Mercury following a 2017 launch from South America's French Guiana. It will take seven years for the two satellites to reach Mercury and enter its orbit, in 2024. The mission is called BepiColombo after the late Italian scientist who came up with the calculations for repeated fly-bys of Mercury by Mariner 10.

Information from The Associated Press was used in this report.