A new image taken minutes before NASA's New Horizons spacecraft was zipped by a rocky object in the Kuiper belt on New Year's Day shows that the two-winged world – nicknamed Ultima Thule – has fascinating fractures and a large Crater-like depression may provide clues to the early history of the solar system.
The image released on Thursday shows Ultima Thule – officially designated as 2014 MU69 – in more detail than images linked down from the New Horizons probe in the hours and days after their appearance in the Kuiper Belt on January 1.
While the earlier images showed the shape and color of Ultima Thule, they did not have the resolution to see finer details, such as craters and textures, that scientists want to see in their quest for a better understanding of icing. rocky material merged into larger objects and eventually formed the planets of the solar system.
The image released on Thursday was taken by the Multicolor Visible Imaging Camer A component of the Ralph instrument on the New Horizons probe at a distance of approximately 6,700 kilometers from Ultima Thule, just seven minutes before the probe's approach to the next Object in the Kuiper belt at 12:33 EST (0533 GMT) on 1 January.
The New Year's flyby made Ultima Thule the farthest object ever explored from close range.
Ultima Thule was not even known to the scientists when New Horizons was launched in 2006. One billion miles beyond Pluto – New Horizons mission's first flyby target in 2015 – Ultima Thule was discovered in 2014 by astronomers who used the Hubble Space Telescope.
"This new image gradually shows differences in the geological character of the two Ultima Thule rags. and also introduces new secrets, "said Alan Stern, chief investigator of the New Horizons mission at the Southwest Research Institute in Boulder, Colorado. "Next month, there will be better color images and better resolution images we hope will solve the many secrets of Ultima Thule."
In a press release accompanying the image on Thursday, officials said that the oblique illumination of the new image reveals topographic details along the day / night boundary or terminator at the top of the image. Scientists have identified numerous small pits with a diameter of up to 0.7 kilometers, and the higher resolution image has also shown a larger circular pit with a diameter of about 4 kilometers on the smaller two Ultima Thule lobes.  "It is not clear whether these pits are impact craters or features that result from other processes, such as" collapse pits "or old venting of volatiles."
"Both rags also show many fascinating aspects of light and dark Patterns of unknown origin, which can give indications of how this body was assembled 4.5 billion years ago during the formation of the solar system, "the press release continues. "One of the most striking of these is the bright" collar "that separates the two lobes."
Scientists believe that two objects formed independently of each other and assembled in a slow collision to form Ultima Thule, which measures about 34 kilometers long) on its largest dimension.
Scientists refer to the larger of the two lobes of the object as Ultima and the smaller Thule. Stern said earlier this month that the New Horizons science team will submit formal nominations for the object and its surface features to the International Astronomical Union later this year.
Each lobe appears somewhat spherical in shape and the larger body has it According to the first scientific article after the New Horizons fly-by
Ultima Thule is the first object of its kind – a category of planetary bodies that scientists call a "bizarre". Lobat contact "call binary" – ever explored by a spaceship that is so far from Earth. The object is also part of a population of objects in the Kuiper Belt – a ring of dwarf planets and smaller rocks beyond the orbit of Neptune – the so-called "cold classics" that have remained in the same zone of the solar system in which they are located originally about 4.5 billion years ago.
The planets, comets, and other objects have come or come from the sun through the history of the solar system. Another known contact binary object, Comet 67P / Churyumov-Gerasimenko, was visited from 2014 to 2016 by the European Space Agency's Rosetta probe.
Stern and members of the New Horizons team wrote in a newspaper on January 9 that Ultima Thule's appearance is in line with a relic planetary body possibly formed by the collapse of a pebble cloud in the outer solar system.
"How MU69's two loves merged, how gentle and how the angular momentum was lost before the final contact is a puzzle that needs to be solved. More data is returned and detailed modeling can be done," Stern and other scientists wrote Newspaper of January 9.
New Horizons detected no sign of a moon or companion of Ultima Thule, although more images need to be analyzed, and scientists in the January 9 newspaper also wrote that the spacecraft's dust counter will be on during the next part The flyby sequence had no effect.
It will take about 20 months for all New Horizons flight data to return to Earth The long distance and slow transfer rate between the antenna of the probe and the receiving harness on the ground.  The picture published on Thursday was on the 18th and 19th of January on the Earth returned after controllers had reestablished contact with New Horizons after a scheduled break. On January 4, as the spacecraft was too close to the sun in the sky to allow reliable communication.
The data stored in the spacecraft data loggers are returned to the scientists a little faster than 1,000 bits per second. The data downlinks are not constant as the probe performs other scientific observations and NASA's Deep Space Network antennas support other interplanetary missions.
New Horizons is currently 6,64 billion kilometers from Earth. At this distance, a radio signal takes six hours and nine minutes to return to Earth from New Horizons.
The final dates of the Ultima Thule encounter are expected to arrive on Earth in September 2020.
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