A Vision of Ultima Thule
Artist's illustration of NASA’s New Horizons spacecraft flying by the distant object 2014 MU69 on Jan. 1, 2019. Early observations hint at the Kuiper Belt object being either a binary orbiting pair or a contact (stuck-together) pair of nearly like-sized bodies with diameters near 12 and 11 miles (20 and 18 kilometers).
One possibility is that Ultima Thule is not one, but two objects, as shown in this illustration.
A Single Target
This rendering depicts Ultima Thule as a single, rocky object.
New Horizons scientists stacked 48 different images taken Aug. 16, 2018, to focus on the location of the spacecraft's next target, 2014 MU69 (left). They also subtracted out the stars in the frame to focus on the object itself (right).
New Horizons Halfway to 2014 MU69
New Horizons took a series of 10-second exposures of the background star field near the location of 2014 MU69, to prepare for the probe’s flyby of the Kuiper Belt object on Jan. 1, 2019. This composite image is made from 45 of these 10-second exposures taken on Jan. 28, 2017. The yellow diamond marks the predicted location of MU69 on approach, but the KBO itself was too far from the probe to be detected.
Occultation of Ultima Thule
In 2017, the shadow of Ultima Thule (then known still as 2014 MU69) passed across Earth, giving New Horizons scientists a chance to learn more about their target. This map shows the path of the shadow across Earth's surface.
New Horizons team members here are seen preparing one of their new 16-inch (40 centimeters) telescopes for deployment to 2014 MU69 occultation observation sites in Argentina and South Africa in June 2017.
Looking for 2014 MU69
Scientists with the International Occultation Timing Association joined with NASA's New Horizons team watch an occultation of the Kuiper Belt Object 2014 MU69 from the Karoo desert near Vosburg, South Africa on June 2-3. During the occultation, the icy space rock passed in front of a distant star and was visible with a telescope for about two seconds. The Horizons spacecraft will fly past it on New Year’s Day 2019.
Kuiper Belt Object 1994 JR1
Ultima Thule is not actually the first Kuiper Belt object New Horizons has seen. First, of course, is Pluto, but the spacecraft also spotted this object, 1994 JR1 on Nov. 2, 2015.
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Tariq is the Editor-in-Chief of Space.com and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became Space.com's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining Space.com, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at Space.com and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.