scholarly journals Organic Components of Small Bodies in the Outer Solar System: Some Results of the New Horizons Mission

Life ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 126
Author(s):  
Dale P. Cruikshank ◽  
Yvonne J. Pendleton ◽  
William M. Grundy

The close encounters of the Pluto–Charon system and the Kuiper Belt object Arrokoth (formerly 2014 MU69) by NASA’s New Horizons spacecraft in 2015 and 2019, respectively, have given new perspectives on the most distant planetary bodies yet explored. These bodies are key indicators of the composition, chemistry, and dynamics of the outer regions of the Solar System’s nascent environment. Pluto and Charon reveal characteristics of the largest Kuiper Belt objects formed in the dynamically evolving solar nebula inward of ~30 AU, while the much smaller Arrokoth is a largely undisturbed relic of accretion at ~45 AU. The surfaces of Pluto and Charon are covered with volatile and refractory ices and organic components, and have been shaped by geological activity. On Pluto, N2, CO and CH4 are exchanged between the atmosphere and surface as gaseous and condensed phases on diurnal, seasonal and longer timescales, while Charon’s surface is primarily inert H2O ice with an ammoniated component and a polar region colored with a macromolecular organic deposit. Arrokoth is revealed as a fused binary body in a relatively benign space environment where it originated and has remained for the age of the Solar System. Its surface is a mix of CH3OH ice, a red-orange pigment of presumed complex organic material, and possibly other undetected components.

Science ◽  
2020 ◽  
Vol 367 (6481) ◽  
pp. eaay3999 ◽  
Author(s):  
J. R. Spencer ◽  
S. A. Stern ◽  
J. M. Moore ◽  
H. A. Weaver ◽  
K. N. Singer ◽  
...  

The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, is composed of primitive objects preserving information about Solar System formation. In January 2019, the New Horizons spacecraft flew past one of these objects, the 36-kilometer-long contact binary (486958) Arrokoth (provisional designation 2014 MU69). Images from the flyby show that Arrokoth has no detectable rings, and no satellites (larger than 180 meters in diameter) within a radius of 8000 kilometers. Arrokoth has a lightly cratered, smooth surface with complex geological features, unlike those on previously visited Solar System bodies. The density of impact craters indicates the surface dates from the formation of the Solar System. The two lobes of the contact binary have closely aligned poles and equators, constraining their accretion mechanism.


Science ◽  
2020 ◽  
Vol 367 (6481) ◽  
pp. eaay6620 ◽  
Author(s):  
W. B. McKinnon ◽  
D. C. Richardson ◽  
J. C. Marohnic ◽  
J. T. Keane ◽  
W. M. Grundy ◽  
...  

The New Horizons spacecraft’s encounter with the cold classical Kuiper Belt object (486958) Arrokoth (provisional designation 2014 MU69) revealed a contact-binary planetesimal. We investigated how Arrokoth formed and found that it is the product of a gentle, low-speed merger in the early Solar System. Its two lenticular lobes suggest low-velocity accumulation of numerous smaller planetesimals within a gravitationally collapsing cloud of solid particles. The geometric alignment of the lobes indicates that they were a co-orbiting binary that experienced angular momentum loss and subsequent merger, possibly because of dynamical friction and collisions within the cloud or later gas drag. Arrokoth’s contact-binary shape was preserved by the benign dynamical and collisional environment of the cold classical Kuiper Belt and therefore informs the accretion processes that operated in the early Solar System.


2004 ◽  
Vol 213 ◽  
pp. 263-270
Author(s):  
K. J. Meech ◽  
J. M. Bauer

We present a summary of ground-based work being done to gain an understanding of primitive comet, Centaur and Kuiper belt object compositions. We are seeing a diversity of compositions in outer solar system small bodies with respect to the presence of water and organics which may reflect both primordial differences and evolutionary processes.


Eos ◽  
2018 ◽  
Vol 99 ◽  
Author(s):  
Jenessa Duncombe

The flyby of Ultima Thule on New Year’s Day will give us our first glimpse of a mysterious Kuiper Belt object.


2021 ◽  
Vol 03 (01) ◽  
pp. 85-87
Author(s):  
Türkanə Mirzəli qızı Əliyeva ◽  
◽  
Vəfa Əjdər qızı Qafarova ◽  

The article provides extensive information on the formation, evolution and structure of the solar system. It also discusses the planets of the solar system and the dwarf planets. Its noted that the Kuiper objects are the celestial bodies which belongs to the solar system. NASA's New Horizons spacecraft is currently helps studying four objects in the Kuiper belt. There is also talked about TTauri type stars. The article discusses the future transformation of the Sun from a Red Giant to a White Dwarf. Key words: Kuiper Belt, T Tauri Star, Dwarf Planets, Planet X


Icarus ◽  
2021 ◽  
Vol 356 ◽  
pp. 113723 ◽  
Author(s):  
Jason D. Hofgartner ◽  
Bonnie J. Buratti ◽  
Susan D. Benecchi ◽  
Ross A. Beyer ◽  
Andrew Cheng ◽  
...  

1998 ◽  
Vol 11 (1) ◽  
pp. 223-228
Author(s):  
R. Malhotra

Ideas about the contents of the Solar System beyond Neptune and Pluto can be traced back to at least Edgeworth (1943, 1949) and Kuiper (1951), who speculated on the existence of pre-planetary small bodies in the outer Solar System beyond the orbit of Neptune - remnants of the accretion process in the primordial Solar Nebula. The basis for the speculation was primarily the argument that the Solar Nebula was unlikely to have been abruptly truncated at the orbit of Neptune, and that in the trans-Neptunian accretion timescales were too long for bodies larger than about ˜ 1000 km in radius to have formed in the 4.5 billion year age of the Solar System. Another important theoretical argument relevant to this region of the Solar System is related to the origin of short period comets. Fernández (1980) suggested that the short period comets may have an origin in a disk of small bodies beyond Neptune, rather than being “captured” from the population of long period comets originating in the Oort Cloud, the latter scenario having considerable difficulty reconciling the observed flux of short period comets with the exceedingly low efficiency of transfer of long period comet orbits to short period ones by means of the gravitational perturbations of the giant planets. The new scenario received further strength in the numerical work of Duncan et al. (1988) and Quinn et al. (1990) which showed that the relatively small orbital inclinations of the Jupiter-family short period comets were not consistent with a source in the isotropic Oort Cloud of comets but could be reproduced with a source in a low-inclination reservoir beyond Neptune’s orbit. Duncan et al. named this hypothetical source the Kuiper Belt, and the name has come into common use in the last decade (although other names are also in use, e.g. Edgeworth-Kuiper Belt, and trans-Neptunian objects). A recent theoretical milestone was the work by Holman and Wisdom (1993) and Levison and Duncan (1993) on the long term stability of test particle orbits in the trans-Neptunian Solar System. This work showed that low-eccentricity, low-inclination orbits with semimajor axes in excess of about 43 AU are stable on billion year timescales, but that in the region between 35 AU and 43 AU orbital stability times range from 107 yr to more than 109 yr [see, for example, figure 1 in Holman (1995)]. Orbital instability in this intermediate region typically leads to a close encounter with Neptune which causes dramatic orbital changes, with the potential for subsequent transfer to the inner Solar System. Thus, this region could in principle serve as the reservoir of short period comets at the present epoch. However, the idea of a kinematically cold — i.e. low-eccentricity, low-inclination — population in this region is at odds with recent observations, and the question of the origin of short period comets remains unsettled at the present time.


Science ◽  
2019 ◽  
Vol 364 (6441) ◽  
pp. eaaw9771 ◽  
Author(s):  
S. A. Stern ◽  
H. A. Weaver ◽  
J. R. Spencer ◽  
C. B. Olkin ◽  
G. R. Gladstone ◽  
...  

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69’s origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.


Eos ◽  
2019 ◽  
Vol 100 ◽  
Author(s):  
Katherine Kornei

The New Horizons spacecraft recorded images of craters that imply an unexpected dearth of small objects in the Kuiper Belt.


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