
A snowman-shaped space rock that formed more 4.6billion years ago and predates every planet in the Solar System may have sparked life on earth, scientists believe.

The unusually-shaped object named Arrokoth - the most distant body ever explored by man - was discovered 4.1 billion miles from Earth by NASA's New Horizons craft.

The man-made spacecraft initially flew past Pluto and then continued on to Arrakoth for its January 1 2019 flyby.

Arrakoth, which was previously called Ultima Thule, sits in the Kuiper Belt and has intrigued astronomers since the first fuzzy images were glimpsed.

Now, high-resolution images painstakingly created reveal more secrets about the most distant object ever studied in detail by humans.

Three studies found the snowball-shaped object was once two separate objects that eventually merged into one, to form the unique shape seen today.

It also revealed a distinctive red hue of the rock which was previously unknown.

This implies the presence of key molecules which could have kick-started life in the Solar System.

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A snowman-shaped space rock named Arrokoth that formed more than four billion years ago and predates every planet in the Solar System may have sparked life on earth, scientists say

Scientists on Thursday offered the fullest description yet of Arrokoth's composition and origin, based on data collected by NASA's New Horizons spacecraft

The New Horizons spacecraft (pictured left) flew past Arrokoth on January 1, 2019 after its initial mission. The unusually-shaped space rock - the most distant body ever explored by man - was discovered 4.1 billion miles from Earth in a region beyond Neptune called the Kuiper Belt. A flight path for the mission New Horizons was on when it spotted Arrokoth is pictured right

WHAT IS ARROKOTH? Ultima Thule, now known as Arrakoth, was originally thought to be two separate objects The Kuiper Belt object was discovered by the Hubble Space Telescope in 2014. Officially known as 2014 MU69, it got the nickname Ultima Thule in an online vote. In classic and medieval literature, Thule was the most distant, northernmost place beyond the known world. It was formally renamed in November 2019 to Arrakoth to avoid unwanted connections to the Nazi regime. Arrokoth means 'sky' in the Powhatan and Algonquian languages. The Nazi party used the phrase 'Ultima thule' to refer to the mythical homeland of the Aryan people. When New Horizons first glimpsed the rocky iceball in August it was just a dot. NASA's New Horizons flew past the object on January 1 2019, 4.1 billion miles from Earth. In 2019, ongoing research into data sent back from new Horizons revealed it was not two items, but a single, snowman-like object In 2019, ongoing research into data sent back from new Horizons revealed it was not two items, but a single connected item. High resolution images revealed it had a 'snowman-like' appearance. It is now the most distant, most primitive and most pristine object ever explored by spacecraft. t is now known to be roughly the size of Seattle at 22 miles long and 12 miles wide. It also boasts a uniformly reddish surface that is smooth and undulating with few craters. It has now been officially classified as a planetesimal, objects that were among the solar system's original building blocks. It has now been officially classified as a planetesimal, objects that were among the solar system's original building blocks. Advertisement

More than a year after the ground-breaking flyby, scientists created the fullest description yet of Arrokoth's composition and origin.

'Arrokoth is the most distant, most primitive and most pristine object ever explored by spacecraft, so we knew it would have a unique story to tell,' New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute in Boulder, Colorado, told a media briefing Thursday.

'It's teaching us how planetesimals formed, and we believe the result marks a significant advance in understanding overall planetesimal and planet formation.'

Arrokoth is roughly the size of Seattle at 22 miles long and 12 miles wide and boasts a uniformly reddish surface that is smooth and undulating with few craters.

No water has yet been found on the body, which is coated with frozen methanol - a type of alcohol - and unidentified complex organic molecules.

It is classified as a planetesimal, objects that were among the solar system's original building blocks.

These small bodies coalesced at an early stage of the solar system's formation some 4.5 billion years ago and are a key intermediate size step on the way to building planets.

Arrokoth is comprised of two lobes looking somewhat like giant wheels of cheese fused together by a bridge.

'It consists of two bodies that appear to have formed in orbit around each other from a local dust cloud, which collapsed under its own gravity within the solar nebula - the huge disk of dust and gas that the solar system formed from,' said astronomer John Spencer of the Southwest Research Institute in Colorado, one of the researchers in the study published in the journal Science.

'The two bodies then spiralled in together and merged very gently.'

This suggests that planetesimals formed in localised conditions in which collision speeds were slow rather than from a gradual assembly of widely dispersed objects growing by randomly colliding with each other at higher speeds.

'So we now have a clearer picture of how planets, including the Earth, were built,' Spencer said.

'Planetesimals previously visited by space probes were all badly battered by impactors or cooked by approaching too close to the sun,' said planetary scientist and study co-author Will Grundy of Lowell Observatory in Arizona, a New Horizons mission co-investigator.

'So it is thrilling to finally be able to see one still pretty much just as it was after its formation.'

Life on Earth has a complex history which spans back around 4.5billion years. Molecules on the asteroid Arrakoth may have played a role in the formation of life

Arrokoth, which is roughly the size of Seattle at 22 miles long and 12 miles wide, boasts a uniformly reddish surface that is smooth and undulating with few craters

The figure above shows how Arrokoth's two lobes collided to form its unique 'snowman' shape

The graphics above, which were included in a study published by a New Horizons research team, show how Arrokoth's surface qualities are determined by its gravity and rotation

Arrokoth is one of the thousands of small icy bodies inhabiting the Kuiper Belt, the solar system's vast 'third zone' beyond the inner terrestrial planets and the outer gas giant planets.

It was initially nicknamed Ultima Thule given its vast distance from Earth, but the name drew backlash over its Nazi connotations.

Scientists announced the official name Arrokoth - which means 'sky' in the Native American Powhatan/Algonquian language - last November.

The New Horizons spacecraft, which was launched in 2006, is now 316 million miles beyond Arrokoth.

The research team is looking for other potential targets to investigate. Powerful ground telescopes still under construction will help survey this part of the sky.

Emerging technology will enable scientists to develop a mission that could put a spacecraft in orbit around Pluto, three billion miles away, according to Stern.

After a few years, that same spacecraft could be sent even deeper into the Kuiper Belt to check out other dwarf planets and objects, he said.