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NASA's New Horizons mission performed the first flyby of a small Kuiper Belt Object (KBO), (486958) Arrokoth on 1 January 2019. The fast flyby revealed a fascinating, flattened, contact binary replete with a variety of unexpected geologic terrains. However, the irregular shape and constraints imposed by the fast flyby makes it a challenge to understand these features. Here we use the latest New Horizons shape models of Arrokoth to investigate its geophysical environment, including its surface slopes, gravity field, and moments of inertia—which are critical context for understanding Arrokoth's formation, evolution, and peculiar geology. We find that Arrokoth's surface features have a complicated relationship to its geophysical environment. For example, bright material tends to be concentrated in geopotential lows (like the neck), consistent with mass wasting—however, this trend is not consistently observed across Arrokoth. Mass wasting may naturally explain some aspects of Arrokoth's geology, but the actual dynamics of material transport may be complicated owing to Arrokoth's unique shape, spin‐rate, and inferred density. While New Horizons's fast and distant flyby precluded directly measuring Arrokoth's mass, we used techniques previously pioneered for comets and asteroids to infer its density. We find that Arrokoth has a low bulk density of ρ = 235 kg/m3 (1σ range: 155–600 kg/m3). This density is low compared to previously explored small bodies, but is comparable to comets, select binary KBOs, and the ring‐moons of Saturn. This low density may be a critical data‐point for understanding the formation of planetesimals at the dawn of the Solar System. Plain Language Summary: NASA's New Horizons mission performed the first flyby of a small Kuiper Belt Object (KBO), (486958) Arrokoth on 1 January 2019. Arrokoth is a ∼30‐km long, peanut shaped, icy body in the Kuiper Belt—a reservoir of small bodies left over from the Solar System's formation. Arrokoth is the most distant, and likely the least evolved object, ever explored by a spacecraft. Arrokoth's unusual shape makes it challenging to determine how material moves across its surface. We use the latest shape models to calculate Arrokoth's gravity field. Bright material tends to collect in Arrokoth's lowest locations, perhaps indicating material can move downslope. While New Horizons was not able to measure the density of Arrokoth, we are able to infer it using techniques pioneered for studying asteroids and comets. We find that Arrokoth's density is extremely low—more akin to fluffy snow on Earth. If correct, this would be one of the lowest density objects ever explored, closer to the densities of some of the comets and small moons within Saturn's rings. Arrokoth's low density may suggests that the building blocks of planets were assembled very gently in the outer Solar System, in the first few million years of Solar System formation. Key Points: We present new models for the geophysical environment of (486958) Arrokoth based on the latest New Horizons shape modelsMany (but not all) of Arrokoth's enigmatic surface markings are correlated with its geophysical environmentAnalysis of Arrokoth's shape suggests that it has a low density of 235 kg/m3 (1σ range: 155–600 kg/m3) [ABSTRACT FROM AUTHOR]

The New Horizons spacecraft returned images and compositional data showing that terrains on Pluto span a variety of ages, ranging from relatively ancient, heavily cratered areas to very young surfaces with few-to-no impact craters. One of the regions with very few impact craters is dominated by enormous rises with hummocky flanks. Similar features do not exist anywhere else in the imaged solar system. Here we analyze the geomorphology and composition of the features and conclude this region was resurfaced by cryovolcanic processes, of a type and scale so far unique to Pluto. Creation of this terrain requires multiple eruption sites and a large volume of material (>104 km3) to form what we propose are multiple, several-km-high domes, some of which merge to form more complex planforms. The existence of these massive features suggests Pluto's interior structure and evolution allows for either enhanced retention of heat or more heat overall than was anticipated before New Horizons, which permitted mobilization of water-ice-rich materials late in Pluto's history. Giant icy volcanos (cryovolcanos) on Pluto are unique in the imaged solar system and provide evidence for unexpected, active geology late in Pluto's history. [ABSTRACT FROM AUTHOR]

Acquiring and processing astrometric measurements of a spacecraft's target using on-board images, generically referred to as optical navigation, is an integral function of the orbit determination and navigation of NASA's New Horizons spacecraft. Since New Horizons' reconnaissance of the Pluto system in July 2015, many preparations have been completed to further enhance the optical navigation system and prepare for the reconnaissance of New Horizons' next target, Kuiper Belt Object (486958) 2014 MU69 (unofficially nicknamed Ultima Thule). Due to its low relative brightness compared to most planetary exploration targets, Ultima Thule presents several unique challenges to the optical navigation system. The optical navigation system design, imaging schedule, and technical algorithms that were developed and tailored to these challenges are explored in detail. Additionally, several operational readiness tests, simulation methods, and test results are presented and analyzed to assess the optical navigation system performance and implications to flight operations. Lastly, a first look at Ultima as viewed from the New Horizons LORRI imager is presented. [ABSTRACT FROM AUTHOR]

The New Horizons instrument named Ralph is a visible/near infrared multi-spectral imager and a short wavelength infrared spectral imager. It is one of the core instruments on New Horizons, NASA’s first mission to the Pluto/Charon system and the Kuiper Belt. Ralph combines panchromatic and color imaging capabilities with SWIR imaging spectroscopy. Its primary purpose is to map the surface geology and composition of these objects, but it will also be used for atmospheric studies and to map the surface temperature. It is a compact, low-mass (10.5 kg) power efficient (7.1 W peak), and robust instrument with good sensitivity and excellent imaging characteristics. Other than a door opened once in flight, it has no moving parts. These characteristics and its high degree of redundancy make Ralph ideally suited to this long-duration flyby reconnaissance mission. [ABSTRACT FROM AUTHOR]

The topography of Neptune's large icy moon Triton could reveal important clues to its internal evolution, but has been difficult to determine. New global digital color maps for Triton have been produced as well as topographic data for <40% of the surface using stereogrammetry and photoclinometry. Triton is most likely a captured Kuiper Belt dwarf planet, similar though slightly larger in size and density to Pluto, and a likely ocean moon that exhibited plume activity during Voyager 2′s visit in 1989. No surface features or regional deviations of greater than ±1 km amplitude are found. Volatile ices in the southern terrains may take the form of extended lobate deposits 300–500 km across as well as dispersed bright materials that appear to embay local topography. Limb hazes may correlate with these deposits, indicating possible surface–atmosphere exchange. Triton's topography contrasts with high relief up to 6 km observed by New Horizons on Pluto. Low relief of (cryo)volcanic features on Triton contrasts with high-standing massifs on Pluto, implying different viscosity materials. Solid-state convection occurs on both and at similar horizontal scales but in very different materials. Triton's low relief is consistent with evolution of an ice shell subjected to high heat flow levels and may strengthen the case of an internal ocean on this active body. [ABSTRACT FROM AUTHOR]

NASA's New Horizons spacecraft has revealed the complex geology of Pluto and Charon. Pluto's encounter hemisphere shows ongoing surface geological activity centered on a vast basin containing a thick layer of volatile ices that appears to be involved in convection and advection, with a crater retention age no greater than ~10 million years. Surrounding terrains show active glacial flow, apparent transport and rotation of large buoyant water-ice crustal blocks, and pitting, the latter likely caused by sublimation erosion and/or collapse. More enigmatic features include tall mounds with central depressions that are conceivably cryovolcanic and ridges with complex bladed textures. Pluto also has ancient cratered terrains up to ~4 billion years old that are extensionally faulted and extensively mantled and perhaps eroded by glacial or other processes. Charon does not appear to be currently active, but experienced major extensional tectonism and resurfacing (probably cryovolcanic) nearly 4 billion years ago. Impact crater populations on Pluto and Charon are not consistent with the steepest impactor size-frequency distributions proposed for the Kuiper belt. [ABSTRACT FROM AUTHOR]

Highlights • Final global mosaic and topographic map of Charon is now complete and archived to PDS. • Charon has greatest topographic variability on an icy world, except for Iapetus. • Deepest features on Charon are 14-km-deep troughs near North pole. • Resurfaced Vulcan Planitia is variable in elevation and depressed several kilometers. • Vulcan Planitia could be due to volcanism of breakup and foundering of Charon's crust. Abstract The 2015 New Horizons flyby through the Pluto system produced the first high-resolution topographic maps of Pluto and Charon, the most distant objects so mapped. Global integrated mosaics of the illuminated surface of Pluto's large icy moon Charon have been produced using both framing camera and line scan camera data (including four-color images at up to 1.47 km pixel scales), showing the best resolution data at all areas of the surface. Digital elevation models (DEMs) with vertical precisions of up to ∼0.1 km were constructed for ∼40% of Charon using stereo imagery. Local radii estimates for the surface were also determined from the cartographic control network solution for the LORRI framing camera data, which validate the stereo solutions. Charon is moderately cratered, the largest of which is ∼250-km across and ∼6 km deep. Charon has a topographic range over the observed hemisphere from lowest to highest of ∼19 km, the largest topographic amplitude of any mid-sized icy body (including Ceres) other than Iapetus. Unlike Saturn's icy moons whose topographic signature is dominated by global relaxation of topography and subsequent impact cratering, large-scale tectonics and regional resurfacing dominate Charon's topography. Most of Charon's encounter hemisphere north of the equator (Oz Terra) is broken into large polygonal blocks by a network of wide troughs with typically 3–6 km relief; the deepest of these occur near the illuminated pole and are up to 13 km deep with respect to the global mean radius, the deepest known surfaces on Charon. The edge of this terrain is defined by large tilted blocks sloping ∼5° or so, the crests of which rise to 5 or 6 km above Charon mean, the highest known points on Charon. The southern resurfaced plains, Vulcan Planitia, consist of rolling plains, locally fractured and pitted, that are depressed ∼1 km below the mean elevation of the disrupted northern terrains of Oz Terra that comprise much of the northern hemisphere (but ∼2–2.5 km below the surfaces of the blocks themselves). These plains roll downward gently to the south with a topographic range of ∼5 km. The outer margins of Vulcan Planitia along the boundary with Oz Terra form a 2-3-km-deep trough, suggesting viscous flow along the outer margins. Isolated massifs 2–4 km high, also flanked by annular moats, lie within the planitia itself. The plains may be formed from volcanic resurfacing of cryogenic fluids, but the tilted blocks along the outer margins and the isolated and tilted massifs within Vulcan Planitia also suggest that much of Charon has been broken into large blocks, some of which have been rotated and some of which have foundered into Charon's upper “mantle”, now exposed as Vulcan Planitia, a history that may be most similar to the disrupted terrains of Ariel. [ABSTRACT FROM AUTHOR]

The 2015 New Horizons flyby has produced the first high-resolution maps of morphology and topography of Pluto and Charon, the most distant objects so mapped. Global integrated mosaics of Pluto were produced using both LORRI framing camera and MVIC line scan camera data, showing the best resolution data obtained for all areas of the illuminated surface, ∼78% of the body. A unique feature of the Pluto imaging data set is the observation of terrains illuminated only by light scattered from atmospheric haze, allowing us to map terrains in the southern hemisphere that would otherwise have been in darkness. MVIC 4-color data were combined with the panchromatic map to produce full color global maps. Digital elevation models (DEMs) over ∼42% of Pluto were produced using combinations of MVIC hemispheric scans and LORRI mosaics, from which slopes at scales of ∼1 km can be determined. Pluto can be divided into regions each with distinct topographic signatures, corresponding with major physiographic terrain types. Large areas of Pluto are comprised of low-relief moderately cratered plains units. Deeply pitted and glaciated plains east of Sputnik Planitia are elevated ∼0.7 km. The most dominant topographic feature on Pluto is the 1200-by-2000-km wide depression enclosing the bright Sputnik Planitia ice sheet, the surface of which is 2.5-to-3.5 km deep (relative to the rim) and ∼2 km deep relative to the mean radius. The partial ring of steep-sided massifs, several of which are more than 5 km high, along the western margins of Sputnik Planitia produce some of the locally highest and steepest relief on Pluto, with slopes of 40–50°. The second major topographic feature is a complex, eroded, ridge-trough system ∼300–400 km wide and at least 3200 km long extending north-to-south along the 155° meridian. This enormous structure has several kilometers of relief. It may predate the large impact event forming the basin, though some post-Sputnik Planitia deformation is evident. The large depressed, partially walled plain, Hyecho Palus, lies due southwest of Sputnik Planitia. Near the center of Hyecho Palus lie the circular constructional edifices Wright and Piccard Montes. Wright Mons rises 4.5 km above these plains, with a central depression ∼4.5 km deep, whereas Piccard Mons, best observed in haze-light, rises ∼5.5 km above the plains but has a bowl-shaped central depression ∼5.5 km below the plains for a total relief of up to 11 km, the greatest observed on Pluto. Both of these features are interpreted as constructional (volcanic?) in nature. Additional prominent topographic features include a 2–3 km high and ∼600 km wide dome centered on the illuminated IAU pole and the amoeboidal plateaus of “bladed” terrains in the equatorial region, which rise 2–5 km above local terrains and are the highest standing geologic units on the encounter hemisphere. The mean elevations in the integrated DEM for the two radio occultation areas are consistent with the 5–6 km difference in elevation as determined independently by the radio experiment, and a limb profile near the egress point confirms the presence of elevated bladed terrains in that area. Local relief of 3–5 km at massifs, troughs and pits supports conclusions that the icy shell of Pluto is relatively rigid. Numerous examples of topographic control of ice or frost deposition occur across Pluto, including the distinct coloration of the polar dome, the elevated terrains of eastern Tombaugh Regio, and along the ridge-trough system, where ridge tops and fossae rims are covered in different ices than at lower elevations. The topographic hypsogram of Pluto's encounter hemisphere is strongly bimodal due to the large Sputnik Planitia depression. Otherwise the topographic signature of Pluto is controlled by deviations from the otherwise dominant low plains, including elevated bladed terrain plateaus and the depressed volcanic province including Wright and Piccard Montes. [ABSTRACT FROM AUTHOR]

The surface of Pluto is more geologically diverse and dynamic than had been expected, but the role of its tenuous atmosphere in shaping the landscape remains unclear. We describe observations from the New Horizons spacecraft of regularly spaced, linear ridges whose morphology, distribution, and orientation are consistent with being transverse dunes. These are located close to mountainous regions and are orthogonal to nearby wind streaks. We demonstrate that the wavelength of the dunes (~0.4 to 1 kilometer) is best explained by the deposition of sand-sized (~200 to ~300 micrometer) particles of methane ice in moderate winds (<10 meters per second). The undisturbed morphology of the dunes, and relationships with the underlying convective glacial ice, imply that the dunes have formed in the very recent geological past. [ABSTRACT FROM AUTHOR]

Bladed Terrain on Pluto consists of deposits of massive CH 4 , which are observed to occur within latitudes 30° of the equator and are found almost exclusively at the highest elevations (> 2 km above the mean radius). Our analysis indicates that these deposits of CH 4 preferentially precipitate at low latitudes where net annual solar energy input is lowest. CH 4 and N 2 will both precipitate at low elevations. However, since there is much more N 2 in the atmosphere than CH 4 , the N 2 ice will dominate at these low elevations. At high elevations the atmosphere is too warm for N 2 to precipitate so only CH 4 can do so. We conclude that following the time of massive CH 4 emplacement; there have been sufficient excursions in Pluto's climate to partially erode these deposits via sublimation into the blades we see today. Blades composed of massive CH 4 ice implies that the mechanical behavior of CH 4 can support at least several hundred meters of relief at Pluto surface conditions. Bladed Terrain deposits may be widespread in the low latitudes of the poorly seen sub-Charon hemisphere, based on spectral observations. If these locations are indeed Bladed Terrain deposits, they may mark heretofore unrecognized regions of high elevation. [ABSTRACT FROM AUTHOR]

The highlands region north and east of Sputnik Planitia can be subdivided into seven terrain types based on their physiographic expression. The northern rough uplands are characterized by jagged uplands and broad troughs, and it may contain a deeply-eroded ancient mantle. Dissected terrain has been interpreted to have been eroded by paleo-glaciation. The smooth uplands and pits terrain contains broad, rolling uplands surrounding complexes of pits, some of which contain smooth floors. The uplands are mantled by smooth-surfaced deposits possibly derived from adjacent pits through low-power explosive cryovolcanism or through slow vapor condensation. The eroded smooth uplands appear to have originally been smooth uplands and pits terrain modified by small-scale sublimation pitting. The bright pitted uplands features intricate texturing by reticulate ridges that may have originated by sublimation erosion, volatile condensation, or both. The bladed terrain is characterized by parallel ridges oriented north–south and is discussed in a separate paper. The dark uplands are mantled with reddish deposits that may be atmospherically deposited tholins. Their presence has affected long-term landform evolution. Widespread pit complexes occur on most of the terrain units. Most appear to be associated with tectonic lineations. Some pits are floored by broad expanses of ices, whereas most feature deep, conical depressions. A few pit complexes are enclosed by elevated rims of uncertain origin. [ABSTRACT FROM AUTHOR]

Modern N 2 ice glaciers flow from highlands to the east of the 750 × 1400 km 2 lowland of Sputnik Planum [ SP ] and merge with the ices of similar composition on SP. We explore the possibility that glaciation may be fed by N 2 sublimation from SP followed by redeposition on the highlands. The uplands to the northeast, north, and west of SP have been erosionally sculpted into a variety of dissected terrains that feature linear depressions (valleys), locally in dendritic networks. We interpret these dissected terrains to have been carved by N 2 glaciers formerly covering the uplands. Depositional glacial landforms (moraines, eskers, outwash) have not been identified, however. N 2 glaciation would have a different erosional manifestation because the substrate (porous water ice and CH 4 -rich mantles) probably has lower density than N 2 , and also because of the lack of freeze-thaw weathering. If sufficiently thick (1–4 km), N 2 glaciers might have experienced basal melting. Past flow of N 2 glaciers from the highlands into SP may have detached and transported the prominent mountainous water ice mountains along the western border of SP . [ABSTRACT FROM AUTHOR]

NASA's New Horizons flyby mission of the Pluto-Charon binary system and its four moons provided humanity with its first spacecraft-based look at a large Kuiper Belt Object beyond Triton. Excluding this system, multiple Kuiper Belt Objects (KBOs) have been observed for only 20 years from Earth, and the KBO size distribution is unconstrained except among the largest objects. Because small KBOs will remain beyond the capabilities of ground-based observatories for the foreseeable future, one of the best ways to constrain the small KBO population is to examine the craters they have made on the Pluto-Charon system. The first step to understanding the crater population is to map it. In this work, we describe the steps undertaken to produce a robust crater database of impact features on Pluto, Charon, and their two largest moons, Nix and Hydra. These include an examination of different types of images and image processing, and we present an analysis of variability among the crater mapping team, where crater diameters were found to average ± 10% uncertainty across all sizes measured (∼0.5–300 km). We also present a few basic analyses of the crater databases, finding that Pluto's craters' differential size-frequency distribution across the encounter hemisphere has a power-law slope of approximately –3.1 ± 0.1 over diameters D ≈ 15–200 km, and Charon's has a slope of –3.0 ± 0.2 over diameters D ≈ 10–120 km; it is significantly shallower on both bodies at smaller diameters. We also better quantify evidence of resurfacing evidenced by Pluto's craters in contrast with Charon's. With this work, we are also releasing our database of potential and probable impact craters: 5287 on Pluto, 2287 on Charon, 35 on Nix, and 6 on Hydra. [ABSTRACT FROM AUTHOR]

New Horizons images of Pluto’s companion Charon show a variety of terrains that display extensional tectonic features, with relief surprising for this relatively small world. These features suggest a global extensional areal strain of order 1% early in Charon’s history. Such extension is consistent with the presence of an ancient global ocean, now frozen. [ABSTRACT FROM AUTHOR]

Fields of pits, both large and small, in Tombaugh Regio (Sputnik Planitia, and the Pitted Uplands to the east), and along the scarp of Piri Rupes, are examples of landscapes on Pluto where we conclude that sublimation drives their formation and evolution. Our heuristic modeling closely mimics the form, spacing, and arrangement of a variety of Tombaugh Regio's pits. Pluto's sublimation modified landforms appear to require a significant role for (diffusive) mass wasting as suggested by our modeling. In our models, the temporal evolution of pitted surfaces is such that initially lots of time passes with little happening, then eventually, very rapid development of relief and rapid sublimation. Small pits on Sputnik Planitia are consistent with their formation in N 2 -dominated materials. As N 2 -ice readily flows, some other ``stiffer'' volatile ice may play a role in supporting the relief of sublimation degraded landforms that exhibit several hundred meters of relief. A strong candidate is CH 4 , which is spectroscopically observed to be associated with these features, but the current state of rheological knowledge for CH 4 ice at Pluto conditions is insufficient for a firm assessment. [ABSTRACT FROM AUTHOR]

The geology and stratigraphy of the feature on Pluto informally named Sputnik Planitia is documented through geologic mapping at 1:2,000,000 scale. All units that have been mapped are presently being affected to some degree by the action of flowing N 2 ice. The N 2 ice plains of Sputnik Planitia display no impact craters, and are undergoing constant resurfacing via convection, glacial flow and sublimation. Condensation of atmospheric N 2 onto the surface to form a bright mantle has occurred across broad swathes of Sputnik Planitia, and appears to be partly controlled by Pluto's obliquity cycles. The action of N 2 ice has been instrumental in affecting uplands terrain surrounding Sputnik Planitia, and has played a key role in the disruption of Sputnik Planitia's western margin to form chains of blocky mountain ranges, as well in the extensive erosion by glacial flow of the uplands to the east of Sputnik Planitia. [ABSTRACT FROM AUTHOR]

We examine the 2.21- μ m band from 19 disk-integrated Charon spectra measured by New Horizons /LEISA in the week leading up to its closest encounter with the Pluto system. These observations cover one Charon rotation period. Additionally, we analyze Charon's 2.21- μ m band from 22 Earth-based spectra obtained over the last two decades. We measure the equivalent width of the 2.21- μ m band from all observations and study it as a function of sub-observer longitude. We find no significant variation in the 2.21- μ m band as Charon rotates. Compared to the same band seen on Nix and Hydra, Charon's 2.21- μ m band is several times weaker. We attribute the 2.21- μ m band to NH 4 Cl based on the appearance of a weaker band at 2.24- μ m. Furthermore, we see two never-before-reported absorption features in Charon's spectrum at 1.60 and 1.63- μ m , which may also be due to NH 4 Cl. If NH 3 -H 2 O-ice mixtures are present on Charon, they must be a small fraction of the disk-average composition to be consistent with the spectrum at 1.99- μ m. • First analysis of Charon spectra obtained by New Horizons on approach to the Pluto-system. • In-depth examination of the 2.21 μ m band using New Horizons and ground-based observations. • No variation in depth observed with respect to longitude, and much weaker absorption than Nix and Hydra. • Band at 2.24 μ m suggests NH 4 Cl is present and possible new spectral features are found at 1.60 and 1.63 μ m. • Formation, evolution, and destruction of NH 4 Cl discussed. [ABSTRACT FROM AUTHOR]

The cameras of New Horizons will provide robust data sets that should be imminently amenable to geological analysis of the Pluto system’s landscapes. In this paper, we begin with a brief discussion of the planned observations by the New Horizons cameras that will bear most directly on geological interpretability. Then we broadly review the major geological processes that could potentially operate on the surfaces of Pluto and its major moon Charon. We first survey exogenic processes (i.e. those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration), and the work of wind. We conclude with an assessment of the prospects for endogenic activity in the form of tectonics and cryovolcanism. [ABSTRACT FROM AUTHOR]

On January 1st 2019, the New Horizons spacecraft flew by the classical Kuiper belt object (486958) Arrokoth (provisionally designated 2014 MU69), possibly the most primitive object ever explored by a spacecraft. The I/F of Arrokoth is analyzed and fit with a photometric function that is a linear combination of the Lommel-Seeliger (lunar) and Lambert photometric functions. Arrokoth has a geometric albedo of p v = 0.21 −0.04 +0.05 at a wavelength of 550 nm and ≈0.24 at 610 nm. Arrokoth's geometric albedo is greater than the median but consistent with a distribution of cold classical Kuiper belt objects whose geometric albedos were determined by fitting a thermal model to radiometric observations. Thus, Arrokoth's geometric albedo adds to the orbital and spectral evidence that it is a cold classical Kuiper belt object. Maps of the normal reflectance and hemispherical albedo of Arrokoth are presented. The normal reflectance of Arrokoth's surface varies with location, ranging from ≈0.10–0.40 at 610 nm with an approximately Gaussian distribution. Both Arrokoth's extrema dark and extrema bright surfaces are correlated to topographic depressions. Arrokoth has a bilobate shape and the two lobes have similar normal reflectance distributions: both are approximately Gaussian, peak at ≈0.25 at 610 nm, and range from ≈0.10–0.40, which is consistent with co-formation and co-evolution of the two lobes. The hemispherical albedo of Arrokoth varies substantially with both incidence angle and location, the average hemispherical albedo at 610 nm is 0.063 ± 0.015. The Bond albedo of Arrokoth at 610 nm is 0.062 ± 0.015. • Geometric albedo > than mean but consistent with distribution of cold classical KBOs. • Maps of normal reflectance & hemispherical albedo of Arrokoth's surface are presented. • Normal reflectance of Arrokoth varies with location with ≈Gaussian distribution. • Normal reflectance distributions of Arrokoth's two lobes are very similar. • Hemispherical albedo varies substantially with both incidence angle and location. [ABSTRACT FROM AUTHOR]