NASA welcomed the New Year with a first-time visit to a mysterious world at the edge of the solar system. At 12:33 a.m. EST on Tuesday, Jan. 1, NASA’s New Horizons spacecraft zoomed past Ultima Thule, a 20-by-10 mile wide twin-lobed body located in the outer reaches of the solar system, a billion miles past Pluto, about four billion miles from the sun, and the furthest world ever visited by human space probe.
NASA reported New Years Day that all went as planned: New Horizons passed about 2,200 miles from Ultima Thule, a world researchers believe to be composed of the primordial building blocks that helped form the sun and planets about 4.6 billion years ago. PBS Newshour reported the encounter represents a milestone in science and exploration (Click here to view online).
The close-up photographs of the encounter take about six hours to reach Earth — the time it takes for radio waves travelling at the speed of light to travel four billion miles. The distance also reduces signal strength, slowing data download to a 500 bit-per second trickle. What’s more, the Earth’s orbit has brought it behind the sun, relative to New Horizon’s position, creating a temporary transmission black-out. More images and information on Ultima Thule is expected in February. NASA reported it may take 20 months to receive all the photos and scientific information New Horizons collected in the recent fly-by.
This image taken by the Long-Range Reconnaissance Imager (LORRI) is the most detailed of Ultima Thule returned so far by the New Horizons spacecraft. It was taken at 5:01 Universal Time on January 1, 2019, just 30 minutes before closest approach from a range of 18,000 miles (28,000 kilometers), with an original scale of 730 feet (140 meters) per pixel. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
NASA scientists, including Principal Investigator Alan Stern, reported Wednesday that Ultima Thule is a “contact binary,” an object created by the slow-motion collision of two smaller sphere-shaped bodies, each of which separately formed by the accretion of dust and gas from when the solar system was first forming billions of years ago.
The larger, now dubbed “Ultima,” is about three times larger than the smaller, “Thule.” The body’s remarkable appearance, Stern reported, is unlike anything seen before and illuminates the processes that built the planets four and a half billion years ago.
“New Horizons is like a time machine, taking us back to the birth of the solar system. We are seeing a physical representation of the beginning of planetary formation, frozen in time,” said Jeff Moore, New Horizons Geology and Geophysics team lead. “Studying Ultima Thule is helping us understand how planets form — both those in our own solar system and those orbiting other stars in our galaxy.”
The two bodies came together in a super slow-motion collision, perhaps as slow as 1 mph. They may have spent billions of years rotating around one another, about once every 15 hours.
The NASA scientists also described how comets explored by probes over the past two decades have often shown similar contact binary structure. The researchers believe the new data will shed light on how planets like Earth formed. More detailed images are expected in the coming days,
The first color image of Ultima Thule, taken at a distance of 85,000 miles (137,000 kilometers) at 4:08 Universal Time on January 1, 2019, highlights its reddish surface. At left is an enhanced color image taken by the Multispectral Visible Imaging Camera (MVIC), produced by combining the near infrared, red and blue channels. The center image taken by the Long-Range Reconnaissance Imager (LORRI) has a higher spatial resolution than MVIC by approximately a factor of five. At right, the color has been overlaid onto the LORRI image to show the color uniformity of the Ultima and Thule lobes. Note the reduced red coloring at the neck of the object. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
The image above is a composite of two images taken by New Horizons’ high-resolution Long-Range Reconnaissance Imager (LORRI), which provides the best indication of Ultima Thule’s size and shape so far. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This sequence of three images, received on Dec. 31, 2018, and taken by the LORRI camera onboard New Horizons at 70 and 85 minutes apart illustrates the rotation of Ultima Thule. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
To get the latest word on New Horizons from NASA, click here.
The images above were taken on Dec. 30, 2018 as New Horizons was a little over a million miles from Ultima Thule. Details on the pictures from NASA:
Just over 24 hours before its closest approach to Kuiper Belt object Ultima Thule, the New Horizons spacecraft has sent back the first images that begin to reveal Ultima’s shape. The original images have a pixel size of 6 miles (10 kilometers), not much smaller than Ultima’s estimated size of 20 miles (30 kilometers), so Ultima is only about 3 pixels across (left panel). However, image-sharpening techniques combining multiple images show that it is elongated, perhaps twice as long as it is wide (right panel). This shape roughly matches the outline of Ultima’s shadow that was seen in observations of the object passing in front of a star made from Argentina in 2017 and Senegal in 2018.
Much more detailed images, and other kinds of data, will be gathered today and tomorrow as New Horizons speeds towards its closest approach to Ultima at 12:33 a.m. EST on Jan. 1. A small sample of these images and other data will be returned to Earth in the next few days, though it will take about 20 months to downlink the full data set.
New Horizons was approximately 1.2 million miles (1.9 million kilometers) from Ultima when this image was taken on Dec. 30, 2018.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
The photos were taken with LORRI — the LOng-Range Reconnaissance Imager — a remarkable camera built to work in the demanding and harsh conditions of deep space. Researchers hope the images will shed light on how planets and the solar system itself formed from gas and dust about 4.6 billion years ago. Other New Horizons instruments detect chemical compositions, surface temperatures and interplanetary dust. The data will serve to enlarge the astronomical atlas of worlds visited and explored by humanity to the far reaches of the solar system.
New Horizons flew by the Pluto System on July 14, 2015. The spacecraft returned a treasure trove of photographs and scientific measurements which have revolutionized our understanding of Pluto, its largest moon, Charon, and several smaller moons. Information gathered by New Horizons showed that Pluto undergoes active geologic processes — despite surface temperatures reaching minus-370 degrees Fahrenheit — and holds a thin atmosphere of nitrogen and methane.
About the size of a grand piano, the New Horizons spacecraft was launched from the Kennedy Space Center on January 19, 2006, atop an Atlas V-Centaur booster rocket. After reaching orbit, the Star 48B third stage engine fired the half-ton probe toward Jupiter.
New Horizons swung by the largest planet in the solar system on February 28, 2007. Jupiter’s gravitational pull sped up the spacecraft and then swung it out toward Pluto. The process shaved off about three years of travel time.
Encouraged by the spacecraft’s near-flawless performance after nine years in space, NASA scientists set New Horizons on course for a second mission to the frozen space beyond Pluto: the Kuiper Belt, a region of the solar system comprised of myriad bodies, such as icy comets, rocky asteroids, dwarf planets, and planetisimals thought to coalesced from gas and dust at the birth of the solar system 4.6 billion years ago.
“Ultima Thule” was an ancient mapmaker’s name for the farthest known part of the world, the last known place — somewhere beyond Greenland (“Thule,” pronounced “TOO-Lee”). Formally known to astronomers as (486958) 2014 MU₆₉, the dwarf planet was discovered by researchers using the Hubble Space Telescope on June 26, 2014.
Astronomers report Ultima Thule takes about 297 years to orbit the sun. It and the other objects in the Kuiper Belt are believed to have remained largely untouched from the time of their formation.
New Horizons’ visit to Ultima Thule may mark the auspicious beginnings to 2019, a year which commemorates the 50th anniversary of mankind’s first manned lunar landing, Apollo 11, when on July 20, 1969 astronauts Neil Armstrong and Edwin “Buzz” Aldrin stepped from the Lunar Module Eagle to explore the surface of the moon, while, overhead, astronaut Michael Collins piloted the Command Module Columbia in orbit around the moon.
What’s next for New Horizons? If all systems stay green, NASA may direct it for a third mission to another unexplored world, a place beyond Ultima Thule. Wow! Oh, wow!
For complete details on the New Horizons mission, and what all the acronyms mean, click here to NASA New Horizons online.