On 1 January 2019 the New Horizons probe will begin transmitting data from Ultima Thule, 4bn miles from Earth in the Kuiper belt.
The Guardian said:Four billion miles from Earth, a swarm of little worlds circles the dark edge of our solar system. The sun is so remote from this place that it appears no brighter than a star. This is the Kuiper belt, a doughnut-shaped ring of icy objects that is one of the most mysterious – and one of the most scientifically intriguing – regions of space around our sun.
The belt is made up of rubble left over from the formation of the sun’s planets billions of years ago, fragments that are a fossil record of the solar system’s birth. For decades, researchers have dreamed of getting a close-up look at one but have been thwarted by the utter remoteness of the Kuiper belt.
But this sad state of scientific ignorance is about to come to an end. On 1 January, the US probe New Horizons – which has been hurtling away from the sun for the past 13 years – will sweep past Kuiper belt object 2014 MU69 and, for the next 24 hours, use its cameras, detectors and scanners to scrutinise this little world in detail. By the end of the probe’s encounter, an object that is currently no more than a dot in astronomers’ telescopes should be transformed into a world rich in astronomical and geological detail.
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Since Ultima Thule’s discovery, scientists have been trying to find out more about this tiny, utterly remote world as New Horizons speeds towards it. The Hubble space telescope has continued its surveys while astronomers have attempted to exploit stellar occultations – which occur when an object like Ultima Thule passes in front of a star and disturbs the light received from it on Earth.
From these observations, scientists believe Ultima Thule is either a single object that is about 20 miles in diameter or is made up of two objects swirling round each other with each component measuring 9 to 12 miles in diameter. It is even possible that Ultima Thule may have a moon or possibly several.
“Ultima Thule could have an atmosphere, rings or several moons,” says Stern. “We are certainly hoping for a lot because we uncovered so many surprises when we got to Pluto. However, we will have to wait until 1 January to discover the truth.”
Many key features about Ultima Thule should become clear to scientists when the first data from New Horizons reaches Earth next month. However, they will have a longer wait before they get the total picture – for it will take months to transmit all the information sent back by New Horizons after sweeps to within 2,200 miles of Ultima Thule in January.
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