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Abstract
Preliminary designs for high thrust, flyby missions to five large
trans-Neptunian Objects are discussed, with an emphasis on Quaoar, but
also including Sedna, Makemake, Haumea, and Eris. The primary focus of
this study was the design of the interplanetary trajectory for Earth
departure dates between 2014 and 2050. The best trajectories identified
use only a Jupiter gravity assist, require a total mission delta-V as
low as 7.15 km/s and have arrival V values at the target comparable to
those of the New Horizons mission to Pluto. Transit times range from
13.57 years for missions to Quaoar to 24.48 years to reach Sedna and
Eris. Jupiter periapse radius is a critical factor for these missions,
with satisfactory trajectories requiring values ranging from 3.5 to 25
planetary radii.
... Flights to such distant objects as Sedna and 2012 VP113are reasonable to carry out with the use of gravity assist of the planets of the Solar system, i.e., with a flight near the planets in order to use their gravitational fields to increase the orbital energy of the spacecraft and purposefully change its trajectory. The article [10] shows the results of studies of the trajectories of the flight to Sedna (as well as to four other TNOs) in 2015-2047. This article considers the Earth-Jupiter-Sedna flight scheme, i.e., the gravitational manoeuvre only at Jupiter is assumed. ...
... As will be shown below, the best flight scheme depends on the launch date: for 2029, 2031 and 2037, the best scheme is EVEEJSed; for 2034 and 2036, EVEEJNSed; and in many cases, adding ΔVα around the Earth-to-Earth aphelion slightly reduces ΔVΣ. Moreover, with a flight duration of 25 years (i.e., approximately the same as that accepted in [10]), the value of ΔVΣ is significantly less than in all cases of trajectories to Sedna considered in [10]. ...
... As will be shown below, the best flight scheme depends on the launch date: for 2029, 2031 and 2037, the best scheme is EVEEJSed; for 2034 and 2036, EVEEJNSed; and in many cases, adding ΔVα around the Earth-to-Earth aphelion slightly reduces ΔVΣ. Moreover, with a flight duration of 25 years (i.e., approximately the same as that accepted in [10]), the value of ΔVΣ is significantly less than in all cases of trajectories to Sedna considered in [10]. ...
The presented research is devoted to the determination and analysis of flight trajectories to the trans-Neptunian object Sedna. In this work, two possible ways of reaching Sedna are considered: a direct flight and a flight including gravity assist manoeuvres. Launch dates for the mission are chosen in 2029-2050. The gravity assist manoeuvres considered in the research can reduce the required value of ΔV and the flight duration. Manoeuvres near Venus and the Earth, as well as Jupiter, Saturn and Neptune are considered. It is shown that for launch windows in 2029-2034, the use of the scheme of flight to Sedna with Venus-Earth-Earth-Jupiter gravity assists as a base can significantly reduce the value of the total ΔV required to reach Sedna under restrictions on the time of flight from 20 to 50 years. It is shown that 2053 seems to be the best time to launch the mission using the Earth-Venus-Earth-Earth-Jupiter-Neptune-Sedna scheme because the launch in this year requires only approximately 5.8 km/s of the total ΔV at a flight duration of 20 years. Additionally, we discuss possible expansions of the mission scenario by combining scientific missions to Sedna and other celestial bodies, such as asteroids or other TNOs. Examples for such expansions were provided for five TNOs: three extreme TNOs, 2012 VP113, (541132) Leleakuhonua (former 2015 TG387), 2013 SY99) and two classical Kuiper Belt objects, (90482) Orcus and (20000) Varuna, as well as for the main belt asteroids (16) Psyche, (20) Massalia and (152) Hilda. The approach within which the flight to a distant trans-Neptunian object was part of a scientific mission to Neptune was also considered.
... Moreover, with the time of flight of 25 yrs (i.e. approximately the same as accepted in (McGranaghan et al., 2011;Kreitzman et al., 2013)), ∆VΣ is significantly less than in all cases of trajectories to Sedna considered in (McGranaghan et al., 2011;Kreitzman et al., 2013). Several flight schemes considered in this paper need approach to Jupiter to a close distance during the gravity assist. ...
... Moreover, with the time of flight of 25 yrs (i.e. approximately the same as accepted in (McGranaghan et al., 2011;Kreitzman et al., 2013)), ∆VΣ is significantly less than in all cases of trajectories to Sedna considered in (McGranaghan et al., 2011;Kreitzman et al., 2013). Several flight schemes considered in this paper need approach to Jupiter to a close distance during the gravity assist. ...
... This section provides a comparison of approaches to solving the problem of flight to trans-Neptunian objects in the proposed article and in (McGranaghan et al., 2011;Kreitzman et al., 2013), and evaluates the advantages and disadvantages of our study. ...
The article focuses on trajectory design to the trans-Neptunian object (90377) Sedna for launch in 2029-2034. Sedna is currently moving to the perihelion at a distance of around 74 au from the Sun. The perihelion passage is estimated to be in 2073-74. That opens up of opportunities to study such a distant object. Known for its orbit and 10 thousand year period, Sedna is an exciting object for deep space exploration. The current research provides two possible scenarios of transfer to Sedna. A direct flight and flights including gravity assist manoeuvres are considered. The present study showed that a direct flight would be practically unrealistic due to the high total characteristic velocity and the time of flight value. Promising scenarios include gravity assist manoeuvres near Venus, Earth, Jupiter, Saturn and Neptune. The analysis of the close approach to asteroids during the flight to Sedna had been performed. Results of the research presented in this article show that the launch in 2029 provides the best transfer conditions in terms of minimum total characteristic velocity. The analysis shows that with a small additional impulses flybys of the large main-belt asteroids (16) Psyche for launch in 2034 and (20) Massalia for launch in 2029 are possible.
... Flights to such a distant object as Sedna, it is reasonable to carry out with the use of gravity assist of the planets of the Solar system, i.e. with a flight near the planets in order to use their gravitational fields to increase the orbital energy of the spacecraft and purposefully change its trajectory. The article [7] shows the results of studies of the trajectories of the flight to Sedna (as well as to four other TNOs) in 2015-2047. This article considers the Earth-Jupiter-Sedna flight scheme, i.e., the gravitational maneuver only at Jupiter is assumed. ...
... As will be shown further, the best flight scheme depends on the launch date: for 2029, 2031 and 2037, the best one is EVEEJSed, for 2034 and 2036 EVEEJNSed; and in many cases, adding ΔV α around the Earth-to-Earth aphelion slightly reduces ΔV Σ . Moreover, with a flight duration of 25 years (i.e., approximately the same as that accepted in [7]), the value of ΔV Σ is significantly less than in all cases of trajectories to Sedna considered in [7]. ...
... As will be shown further, the best flight scheme depends on the launch date: for 2029, 2031 and 2037, the best one is EVEEJSed, for 2034 and 2036 EVEEJNSed; and in many cases, adding ΔV α around the Earth-to-Earth aphelion slightly reduces ΔV Σ . Moreover, with a flight duration of 25 years (i.e., approximately the same as that accepted in [7]), the value of ΔV Σ is significantly less than in all cases of trajectories to Sedna considered in [7]. ...
This research is devoted to the determination and analysis of trajectories to the trans-Neptunian object Sedna in launch windows within the 2029-2037 period. Brief analysis has been carried out for the launch within 2029-2034 and a more detailed one was performed for 2036 and 2037 launch years. The gravity assist maneuvers considered in the research can reduce the required value of ∆V and flight duration. Gravity assists of Venus, Earth and giant planets are considered. It is shown that for launch windows in the considered time interval, the use of the Venus, Earth, and Jupiter gravity assists, can significantly reduce the value of the total ∆V required to reach Sedna, with the time of flight limited by 50 years. On the other hand, possibility of reducing the ∆V with help of the Neptune gravity field, does happen on the launch in 2034 and 2036 with the time of flight of about 27.5 years or more. The inclusion of Saturn gravity assist into the flight schemes reduce total ∆V for launch in 2036 and 2037.
... Researches toward studies of a flight to Sedna began since 2011. The paper [22] defines the best scenario of reaching Sedna with a single Jupiter gravity assist (JGA). According to [22], such a flight would require a total cost of 7.42 km/s of characteristic velocity (ΔV) and a time of flight (TOF) of 24.48 yrs. ...
... The paper [22] defines the best scenario of reaching Sedna with a single Jupiter gravity assist (JGA). According to [22], such a flight would require a total cost of 7.42 km/s of characteristic velocity (ΔV) and a time of flight (TOF) of 24.48 yrs. It is worth highlighting the studies carried out in the paper [23], which considers flight scenarios to Varuna, Haumea, Makemake, Ixion and Sedna. ...
Current research focuses on designing fast trajectories to the trans-Neptunian object (TNO) (90377) Sedna to study the surface and composition from a close range. Studying Sedna from a close distance can provide unique data about the Solar System evolution process including protoplanetary disc and related mechanisms. The trajectories to Sedna are determined considering flight time and the total characteristic velocity (${\Delta}V$) constraints. The time of flight for the analysis was limited to 20 years. The direct flight, the use of gravity assist manoeuvres near Venus, the Earth and the giant planets Jupiter and Neptune, and the flight with the Oberth manoeuvre near the Sun are considered. It is demonstrated that the use of flight scheme with ${\Delta}VEGA$ (${\Delta}V$ and Earth Gravity Assist manoeuvre) and Jupiter-Neptune gravity assist leads to the lowest cost of ${\Delta}V$=6.13 km/s for launch in 2041. The maximum payload for schemes with ${\Delta}$VEGA manoeuvre is 500 kg using Soyuz 2.1.b, 2,000 kg using Proton-M and Delta IV Heavy and exceeds $12,000$ kg using SLS. For schemes with only Jupiter gravity assist, payload mass is twice less than for ones with ${\Delta}$VEGA manoeuvre. As a possible expansion of the mission to Sedna, it is proposed to send a small spacecraft to another TNO during the primary flight to Sedna. Five TNOs suitable for this scenario are found, three extreme TNOs 2012 VP113, (541132) Lele\=ak\=uhonua (former 2015 TG387), 2013 SY99) and two classical Kuiper Belt objects: (90482) Orcus, (20000) Varuna.
... Researches toward studies of a flight to Sedna began since 2011. The paper [22] defines the best scenario of reaching Sedna with a single JGA. According to Ref. [22], such a flight would require a total cost of 7.42 km/s of characteristic velocity (ΔV) and a TOF of 24.48 yrs. ...
... The paper [22] defines the best scenario of reaching Sedna with a single JGA. According to Ref. [22], such a flight would require a total cost of 7.42 km/s of characteristic velocity (ΔV) and a TOF of 24.48 yrs. It is worth highlighting the studies carried out in the paper [23], which considers flight scenarios to Varuna, Haumea, Makemake, Ixion and Sedna. ...
Current research focuses on designing fast trajectories to the trans-Neptunian object (TNO) (90377) Sedna to study the surface and composition from a close range. Studying Sedna from a close distance may provide unique data about the earliest stages of the Solar System evolution, including the protoplanetary disc stage and related mechanisms. The trajectories to Sedna are determined considering flight time and the total characteristic velocity (ΔV) constraints. The time of flight for the analysis was limited to 20 years. The direct flight, the use of gravity assist manoeuvres near Venus, the Earth and the giant planets Jupiter and Neptune, and the flight with the Oberth manoeuvre near the Sun are considered. It is demonstrated that the use of flight scheme with ΔVEGA (ΔV and Earth Gravity Assist manoeuvre) and Jupiter-Neptune gravity assist leads to the lowest cost of ΔV≈6.13 km/s for launch in 2041. The maximum payload for schemes with ΔVEGA manoeuvre is 500 kg using Soyuz 2.1.b, 2000 kg using Proton-M and Delta IV Heavy and exceeds 12,000 kg using SLS. For schemes with only Jupiter gravity assist, payload mass is twice less than for ones with ΔVEGA manoeuvre. As a possible expansion of the mission to Sedna, it is proposed to send a small spacecraft to another TNO during the primary flight to Sedna. Five TNOs suitable for this scenario are found, three extreme TNOs 2012 VP113, (541132) Leleākūhonua (former 2015 TG387), 2013 SY99) and two classical KBOs: (90482) Orcus, (20000) Varuna.
... In response, an effort has been made by several teams to identify target objects and trajectories to this distant region. [1][2][3][4][5][6][7][8][9][10][11][12] Our group has evaluated a wide range of mission types to the Kuiper Belt; these studies have considered both high and low thrust propulsion systems, the use of Jupiter gravity assist and ΔV Earth Gravity Assist (ΔVEGA) maneuvers, the feasibility of orbital capture, the possibility of a single probe intercepting two TNOs, and the potential for multiple probes to be launched on a single rocket, with each probe destined for a different target TNO. [1][2][3][4][5][6][7][8] Zangari and colleagues also cast a broad net and describe a wide array of single and double gas giant swingby trajectories to a total of 46 potential TNO targets. ...
... [1][2][3][4][5][6][7][8][9][10][11][12] Our group has evaluated a wide range of mission types to the Kuiper Belt; these studies have considered both high and low thrust propulsion systems, the use of Jupiter gravity assist and ΔV Earth Gravity Assist (ΔVEGA) maneuvers, the feasibility of orbital capture, the possibility of a single probe intercepting two TNOs, and the potential for multiple probes to be launched on a single rocket, with each probe destined for a different target TNO. [1][2][3][4][5][6][7][8] Zangari and colleagues also cast a broad net and describe a wide array of single and double gas giant swingby trajectories to a total of 46 potential TNO targets. 9 Taking a different approach, Zubko's group has focused almost entirely on missions to Sedna and looked in great detail at exquisite and complex trajectories involving multiple inner planet gravity assists. ...
The recent success of the New Horizons mission has heightened public
interest and awareness of the distant, poorly-understood region of the
Solar System known as the Kuiper Belt. The current study was designed
to identify promising trajectories to additional targets among the
thousands of trans-Neptunian objects that have now been cataloged. The
objective was to maximize the potential mass on target, while
maintaining reasonable values of transit time, arrival excess speed and
planetary flyby distances. The approach was to combine a ΔV Earth
gravity assist with a Jupiter flyby. The addition of the ΔVEGA lengthens
the transit time by approximately two years but allows departure C3
values under 30 km2/s2, resulting for many cases in a mass on target of
over 2000 kg for launch on an Atlas V 551. Promising trajectories using
this architecture and departing Earth between 2029 and 2042 are
presented for seven targets, including Sedna, which will reach the
perihelion of its 11,400 year orbit in 2076.
... In a very detailed and well-documented body of work, Zubko et al. have explored a wide range of trajectory designs for Sedna missions, including trajectories reaching the target in as little as twelve years [4,5,10]. Our group has previously examined a wide range of TNO missions [6,7], including a handful of Earth -Jupiter -Sedna trajectories. In this study, we also extend that work to examine the feasibility of lander missions using currently available or soon-to-be available, American launch vehicles. ...
This study aims to explore various orbital trajectories to reach the trans-Neptunian object Sedna. In addition to the opportunity to observe Sedna's physical properties such as its surface composition and atmosphere, such a mission may yield insight into the early history of the Solar System due to the remoteness of trans-Neptunian objects. We compare trajectories by their C3 values, transit times, arrival speeds, Jupiter flyby distances, and Jupiter radiation dosages. The possibility of a lander mission is also considered.
... Previous papers by our group have identified mission opportunities to dozens of TNOs. [2][3][4][5][6][7][8][9] Most of these have focused on flyby opportunities; however, recent papers have researched the feasibility of capturing into orbit about the target objects. 10 This would allow for prolonged study of the body as opposed to the brief amount of time a spacecraft on a flyby trajectory is allotted for observation. ...
... The same approach was used for Pioneer 10 and New Horizons, and has been proposed for the Interstellar Probe as well as numerous missions to trans-Neptunian objects. [5][6][7][8][9][10][11][12] METHODOLOGY Trajectories to Planet Nine were formulated using the software packages Celestia and Mission Analysis Environment (MAnE). 13,14 Celestia is a downloadable, digital orrery that allows the user to visualize the solar system in the past, present, and future. ...
Planet Nine is a large body believed to exist in the outermost part of the solar system hundreds of astronomical units from Earth. A recent study identified the most probable values for five of the planet's orbital elements, but not for true anomaly. In the current paper, potential trajectories to Planet Nine are examined. Since true anomaly is unknown, a family of trajectories is simulated, and critical mission parameters are examined as a function of its assumed value. Due to the extreme distances involved, high-thrust architectures using a single Jupiter gravity assist have transit times of 48 to 67 years. Because of their infrequent availability, trajectories using multiple outer planet flybys do not currently appear to be a practical way of decreasing mission duration. The use of a powered Jupiter flyby, however, can provide decreases of several years in transit time but may require a substantial propellant expenditure.
... These missions focused on Jovian gravity assists (JGA) using an Atlas V 551 rocket with a Star 48 upper stage for launch. [3][4][5][6][7][8][9][10] The current study builds on previous work and investigates the addition of delta-V Earth gravity assists (delta-VEGA) along side Jovian gravity assists to optimize critical performance parameters, with a focus on minimizing launch C 3 and maximizing probe mass while maintaining reasonable transit times. Current missions target TNOs not previously considered, including 2001 U R 163 , Lempo, and Orcus, which have orbital resonance with Neptune; Kagara, a binary cubewano suspected to be undergoing mutual occultation until 2035 if itself and its companion are both spheres; and Arrokoth, a cold contact binary cubewano formed from two planetesimals that orbit with low inclination and low eccentricity. ...
This study is a continuation of previous efforts to identify trajectories to trans-Neptunian objects (TNO). The current work focuses on the use of delta-V Earth gravity assist maneuvers in
combination with Jovian gravity assists to improve overall mission performance and launch
characteristics. Launch is assumed to be accomplished using an Atlas V 551, and a HiPAT
motor is used for deep space maneuvers. Missions to fourteen TNOs are presented, visiting
a wide variety of object types including binaries, cubewanos, plutinos, a trinary system, and
objects both with and without orbital resonance with Neptune. All fourteen missions are
generally favorable in terms of C3, transit time, arrival excess speed and achievable probe
mass when compared to more direct mission architectures. Additionally, four targets are
examined for the possibility of orbital capture. Overall, the missions presented in this study
would allow scientists to observe materials present at the beginning of the formation of the
solar system and result in an increased understanding of the Kuiper Belt.
We present measurements at optical wavelengths of the spectral reflectance, rotational light curve, and solar phase curve of 2003 EL61. With apparent visual magnitude 17.5 at 51 AU from the Sun, this newly discovered member of the classical Kuiper Belt is now the third brightest KBO after Pluto and 2005 FY9. Our observations reveal an unambiguous, double-peaked rotational light curve with period 3.9154 ± 0.0002 hr and peak-to-peak amplitude 0.28 ± 0.04 mag. This is the fastest rotation period reliably determined for any body in the solar system larger than 100 km. Assuming the body has relaxed over time to the shape taken by a homogenous fluid body, our observations tightly constrain the shape and density. Given the mass we recently determined for 2003 EL61 from the orbit of a small satellite, we also constrain the size and albedo. We find a total length of 1960-2500 km, a mean density of 2600-3340 kg m -3, and a visual albedo greater than 0.6. We also measure a neutral reflectance at visible wavelengths and a linear phase curve with slope varying from 0.09 mag deg-1 in the B band to 0.13 mag deg-1 in the I band. The absolute V-band magnitude is 0.444 ± 0.021. © 2006. The American Astronomical Society. All rights reserved.
This paper gives a quantitative comparison of short trip time, direct transfer Earth-Pluto trajectories having launch windows in 1999, 2000, and 2001 that require Titan IV/Centaur launch vehicles with gravity-assist Earth-Jupiter-Pluto trajectories having launch windows in 2002, 2003, and 2004 for the exploration of Pluto. It is shown that by utilizing fast, gravity-assist Earth-Jupiter-Pluto trajectories rather than fast, direct transfer Earth-Pluto trajectories, missions to Pluto can be accomplished with much larger spacecraft using much smaller launch vehicles. This will result in a major cost reduction and, at the same time, provide a major increase in scientific return.
The Kuiper belt contains a vast number of objects in a flattened, ring-like volume beyond the orbit of Neptune. These objects
are collisionally processed relics from the accretion disk of the Sun and, as such, they can reveal much about early conditions
in the Solar system. At the cryogenic temperatures prevailing beyond Neptune, volatile ices have been able to survive since
the formation epoch 4.5 Gyr ago. The Kuiper belt is the source of the Centaurs and the Jupiter-family comets. It is also a
local analogue of the dust disks present around some nearby main-sequence stars. While most Kuiper belt objects are small,
roughly a dozen known examples have diameters of order 1000 km or more, including Pluto and the recently discovered (and possibly
larger) giant Kuiper belt objects 2003 UB313, 2003 EL61 (a binary and a triple system, resp.) and 2005 FY9.
The primary goal of the New Horizons Pluto–Kuiper Belt mission is to explore Pluto by 2020, before Pluto's atmosphere collapses as predicted by scientists, and then explore the Kuiper Belt objects in an extended mission. The baseline mission plans to launch in January 2006, using a Jupiter gravity assist trajectory to reach Pluto. The New Horizons spacecraft will arrive at Pluto as early as 2015, depending on the launch vehicle. For such a mission, whose exploration takes place during a brief flyby period after a long cruise, a thorough planning of the encounter is especially critical to the realization of optimal science observations. A detailed Pluto encounter trajectory design that achieves both solar occultation and Earth occultation by both Pluto and Charon is described in this paper, along with discussions of the design rationale and considerations. Science observations and measurements planned for the Pluto–Charon encounter are simulated and analyzed, and a comprehensive Pluto–Charon encounter process filled with detailed science observation simulations is demonstrated in a 3-D animation.
A new and innovative type of gridded ion thruster, the “Dual-Stage 4-Grid” or DS4G concept, has been proposed and its predicted high performance validated under an ESA research, development and test programme. The DS4G concept is able to operate at very high specific impulse and thrust density values well in excess of conventional 3-grid ion thrusters at the expense of a higher power-to-thrust ratio. This makes it a possible candidate for ambitious missions requiring very high delta-V capability and high power. Such missions include 100 kW-level multi-ton probes based on nuclear and solar electric propulsion (SEP) to distant Kuiper Belt Object and inner Oort cloud objects, and to the Local Interstellar medium. In this paper, the DS4G concept is introduced and its application to this mission class is investigated. Benefits of using the DS4G over conventional thrusters include reduced transfer time and increased payload mass, if suitably advanced lightweight power system technologies are developed.
The discovery of dwarf planet Eris was followed shortly by the discovery of its satellite, Dysnomia, but the satellite orbit,
and thus the system mass, was not known. New observations with the Keck Observatory and the Hubble Space Telescopes show that
Dysnomia has a circular orbit with a radius of 37,350 � 140 (1-σ) kilometers and a 15.774 � 0.002 day orbital period around
Eris. These orbital parameters agree with expectations for a satellite formed out of the orbiting debris left from a giant
impact. The mass of Eris from these orbital parameters is 1.67 × 1022 � 0.02 × 1022 kilograms, or 1.27 � 0.02 that of Pluto.
We report the discovery of the minor planet 2003 VB12 (popularly named Sedna), the most distant object ever seen in the solar system. Pre-discovery images from 2001, 2002, and 2003 have allowed us to refine the orbit sufficiently to conclude that 2003 VB12 is on a highly eccentric orbit which permanently resides well beyond the Kuiper belt with a semimajor axis of 480$\pm$40 AU and a perihelion of 76$\pm$4AU. Such an orbit is unexpected in our current understanding of the solar system, but could be the result of scattering by a yet-to-be-discovered planet, perturbation by an anomalously close stellar encounter, or formation of the solar system within a cluster of stars. In all of these cases a significant additional population is likely present, and in the two most likely cases 2003 VB12 is best considered a member of the inner Oort cloud, which then extends to much smaller semimajor axes than previously expected. Continued discovery and orbital characterization of objects in this inner Oort cloud will verify the genesis of this unexpected population. Comment: to be published in ApJL, 10 August 2004
We have used the Hubble Space Telescope to directly measure the angular size of the large Kuiper belt object 2003 UB313. By carefully calibrating the point spread function of a nearby field star, we measure the size of 2003 UB313 to be 34.3$\pm$1.4 milliarcseconds, corresponding to a diameter of 2400$\pm$100 km or a size $\sim5$% larger than Pluto. The V band geometric albedo of 2003 UB313 is $86\pm7$%. The extremely high albedo is consistent with the frosty methane spectrum, the lack of red coloring, and the lack of observed photometric variation on the surface of 2003 UB313. Methane photolysis should quickly darken the surface of 2003 UB313, but continuous evaporation and redeposition of surface ices appears capable of maintaining the extreme alebdo of this body.
We present the discovery and initial physical and dynamical characterization of the object 2003 UB313. The object is sufficiently bright that for all reasonable values of the albedo it is certain to be larger than Pluto. Pre-discovery observations back to 1989 are used to obtain an orbit with extremely small errors. The object is currently at aphelion in what appears to be a typical orbit for a scattered Kuiper belt object except that it is inclined by about 44 degrees from the ecliptic. The presence of such a large object at this extreme inclination suggests that high inclination Kuiper belt objects formed preferentially closer to the sun. Observations from Gemini Observatory show that the infrared spectrum is, like that of Pluto, dominated by the presence of frozen methane, though visible photometry shows that the object is almost neutral in color compared to Pluto's extremely red color. 2003 UB313 is likely to undergo substantial seasonal change over the large range of heliocentric distances that it travels; Pluto at its current distance is likely to prove a useful analog for better understanding the range of seasonal changes on this body. Comment: 9 pages, 1 figure