page_title: Long Range Reconnaissance Imager
section_title: 15810 Arawn
hierarchical_section_title: Long Range Reconnaissance Imager / 15810 Arawn
caption_attribution_description: English: In April 2016, NASA's New Horizons spacecraft observed 1994 JR1, a 90-mile (145-kilometer) wide Kuiper Belt object (KBO) orbiting more than 3 billion miles (5 billion kilometers) from the sun, for the second time. Taken with the spacecraft's Long Range Reconnaissance Imager (LORRI) on April 7-8 from a distance of about 69 million miles (111 million kilometers), the images shatter New Horizons' own record for the closest-ever views of this KBO in November 2015, when New Horizons detected JR1 from 170 million miles (280 million kilometers) away. Combining the November 2015 and April 2016 observations allows scientists to pinpoint the location of JR1 to within 1,000 kilometers (about 600 miles), far better than any small KBO. The more accurate orbit also allows the science team to dispel a theory that JR1 is a quasi-satellite of Pluto. From the closer vantage point of the April 2016 observations, the team also determined the object's rotation period, observing the changes in light reflected from JR1's surface to determine that it rotates once every 5.4 hours (or a JR1 day). The observations are great practice for possible close-up looks at about 20 more ancient Kuiper Belt objects that may come in the next few years, should NASA approve an extended mission. New Horizons flew through the Pluto system on July 14, 2015, making the first close-up observations of Pluto and its family of five moons. The spacecraft is on course for an ultra-close flyby of another Kuiper Belt object, 2014 MU69, on Jan. 1, 2019. Above, the first two of the 20 observations that New Horizons made of 1994 JR1 in April 2016. The Kuiper Belt object is the bright moving dot indicated by the arrow. The dots that do not move are background stars. The moving features in the top left and far right are internal camera reflections (a kind of selfie) caused by illumination by a very bright star just outside of LORRI's field of view; the one on the left shows the three arms that hold up LORRI's secondary mirror.
context_page_description: Long Range Reconnaissance Imager is a telescope aboard the New Horizons spacecraft for imaging. LORRI has been used to image Jupiter and its moons and especially Pluto and its system of moons since its launched in 2006. LORRI is a reflecting telescope of Ritchey-Chrétien design, and it has a main mirror diameter of 20.8 cm across. Images are taken with a CCD capturing data with 1024 × 1024 pixels. LORRI is a telescopic panchromatic imager integrated with the New Horizons spacecraft, and it is one of seven major science instruments on the probe. LORRI does not have any moving parts and is pointed by moving the entire New Horizons spacecraft. LORRI has a narrow field of view, less than a third of one degree.
context_section_description: In 2016 New Horizons oberved the Kuiper belt object, 15810 Arawn. Arawn is the object that is pointed with an arrow.
caption: KBO 15810 Arawn by New Horizons in April 2016.