A new image shot a few minutes ago by NASA's New Horizons, shot from a rocky spot in the Kaiper's New Year's Eve, shows a double-divided world called Ultima Thule covered with intriguing fractures and a big crater depression that can provide clues about the early history of the solar system.
The picture, published Thursday, shows Ultima Thule – officially called 2014 MU69 – in more detailed details of the images released by the spacecraft New Horizons in the hours and days after meeting in the Kaiper belt on January 1.
While earlier images showed the shape and color of Ultima Thule, they were unable to recognize subtle details such as craters and textures that scientists wanted to see in their quest to better understand how the icy rocky material merged, to form larger objects, eventually forming the planets of the Solar System.
The picture, published Thursday, was photographed by the Multicolor Visible Imaging Camera component of the New Horizons spacecraft Ralph at a distance of about 4,200 miles (6700 km) from Ultima Thule, just seven minutes before the approach probe approach to the Belt Kaiper at 12:33 EST (0533 GMT) on January 1.
New Year's flight made Ultima Thule the most remote object ever explored from a distance.
Ultima Thule is not even known to scientists when New Horizons started in 2006. They are located at billions of miles from Pluto, New Horizons' first destination in 2015. Ultima Thule was opened in 2014 by astronomers using the Hubble Space Telescope .
"This new image begins to reveal the geological differences between the two Ultima Thule shovels and introduces new mysteries," says Alan Stern, chief investigator at Newworld Research at Newworld Research Institute in Boulder. , Colorado. "Next month we will have better colors and better dividing images that we hope will help uncover the ultimate mystery of Ultima Thule."
In a press release accompanying Thursday's image, the authorities said that the sloping lighting of the new photo revealed topographical details on the day / night boundary or a terminator near the top of the picture. Scientists have identified numerous small pits with a diameter of 0.7 miles and a higher resolution image also reveals a larger circular depression of about 4 miles (7 km) in the smaller of the two the Ultima Thule shovel.
"It is unclear whether these pits are impact craters or features stemming from other processes such as" pile collapse "or an ancient release of volatile materials," officials wrote in the press release.
"Both shovels show many interesting light and dark templates of unknown origin that can reveal clues about how this body was assembled during the formation of the solar system 4.5 billion years ago," the press release said. One of the most impressive is the "collar" light that separates the two shovels.
Scientists believe that two sites have formed themselves and merged into a slow-speed collision to create Ultima Thule, 34 miles (34 miles) long in its largest dimension.
Scientists mean the larger of the two shovels on the site, like Ultima, and the smaller Thule. Stern said earlier this month that New Horizons' scientific team will present official proposals to name the site and its features on the surface of the International Astronomical Union later this year.
Each lobe looks approximately spherical in shape, and the larger body has about 2.6 times the internal volume of the smaller one, according to the first scientific article written after the New Horizons flight.
Ultima Thule is the first object of its kind – a category of planetary bodies that scientists call a bi-binary contact pair – ever explored by a spacecraft so far off Earth. The object is also part of a population of objects in the Kaiper belt – a ring of dwarf planets and smaller rock blocks outside Neptune's orbit – called "cold classics," which have remained in the same area of the solar system in which they originally formed about 4.5 billion years ago.
Planets, comets and other objects were drifting closer or farther away from the sun through the history of the Solar System. Another known binary contact site, Comet 67P / Churumov-Gerasimenko, was visited by the spacecraft of the European Space Agency Rosetta from 2014 to 2016.
Stern and members of the New Horizons team wrote in a report on January 9 that the appearance of Ultima Thule is in line with the relict planetary body that may have been created by the collapse of the cloud in the outer solar system.
"How are the two love of MU69 merging, how gentle and how the angular impulse is lost before the final contact, the puzzles have to be resolved when more data is returned and detailed modeling can be done," Stern and other scientists wrote.
New horizons did not find any signs of a moon or companion of Ultima Thule, although there are still more images to be analyzed. The scientists in the January 9th book also wrote that the spacecraft's dust counter had not recorded any impact during the closest part of the flight sequence.
It will take about 20 months for all New Horizons data to return to Earth due to the vast distance and slow transfer speed between the antenna of the probe and the reception of vessels on the ground.
The picture, released on Thursday, was returned to Earth on January 18 and 19, after controllers re-established the New Horizons after a planned interruption that began on January 4 when the spacecraft was too close to the sun in the sky to allow for reliable communication.
The data stored in the spacecraft data recorders will return back to scientists a bit faster than 1000 bits per second. The data will not be permanent as the probe conducts other scientific observations and NASA's Deep Space Network antennas support other interplanetary missions.
Currently, New Horizons is 4.13 billion miles (6.64 billion kilometers) from Earth. At this distance a radio signal takes six hours and nine minutes to travel from New Horizons to Earth.
It is expected that the final data from the Ultima Thule will arrive on Earth by September 2020.
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