Astronomer Gerald Kuiper

Gerald Kuiper, an astronomer, discovered the Kuiper Belt in 1951. (Duncan1995). He proposed that a belt of frozen objects existed in the solar system outside the orbit of the planet Neptune. The field encompasses approximately 50 Astronomical Units and includes trillions of comets and ice particles of various sizes. The enormous number of objects in the field has prompted research probes and missions to attempt to understand their chemical composition and physical properties. The numerous objects in the Kuiper Belt are thought to be traces of the solar system’s creation 13 billion years ago (Christian 17). The objects in the Kuiper Belt so far discover are just handfuls including 1992QB1, comets, dwarf planets (Pluto, Eris) and Haumea. Since most of the Kuiper Belt Objects are several Austromical Units from the earth, it is not easy to precisely measure their sizes. The diameter has to be calculated based on reflective assumptions of the object’s surface. Advancement in technology has made it possible to determine the sizes of the largest Kuiper Belt Objects using the Spitzer Space Telescope, which uses the infrared portion of the electromagnetic spectrum.

The 1992QB1

Astronomers David Jewitt, University of Hawaii and Jane Luu of the University of California made earliest discoveries of the first Kuiper Belt Object. They used the University of Hawaii’s 2.2 m telescope looking on and off in the heavens searching for dim objects beyond Neptune starting from 1987. In 1992 after having done five years of extensive research and searching, they found out a reddish object in the region beyond the orbit of Neptune. It was 37 and 44 AU from the earth and the sun respectively with an indeterminate orbit. Its red color appearance was attributed to a surface rich in organics (Jewitt 5611). It came to be cataloged as 1992QB1 in the International Astronomical Union Circular 5611 although they had wanted to name it Smiley (Jevvitt 362). According to NASA, the two scientists initially believed the outer solar system was not empty.

Comets

The discovery of the 1992QB1 opened a way for understanding the long-sought Kuiper Belt. It was now possible to explain the mystery of comets which periodically pass near the sun in elliptical orbits at perihelion. According to NASA, one of the most baffling mysteries about comets was they were perceived as long-haired stars that appeared in the sky at unannounced times and they were unpredictable. Comets came to be understood as leftovers from the formation of the solar system consisting of ice coated dark organic matter. They are sometimes referred to as dirty snowballs (Keller 8). Attempts to explore comets begun as early as 1070 with Bayeux Tapestry used to picture a comet later came to be called Halley’s. Edmond Halley in 1705 published about a periodic comet of 1531,1607, and 1682, which returned in 1758 as he had predicted and was later, named Halley’s comet. Comets, sometimes can hit the planets as they approach or leave the sun. Scientists observed one such occurrence in 1994 as comet Shoemaker-Levy 9 smashed into the atmosphere of Jupiter. Technological advancements have enabled scientists to collect a building block of life called amino acid glycine from comet Wild 2 by the Stardust spacecraft.

The Dwarf Planet Pluto

The dwarf planet Pluto is the largest known object in the Kuiper Belt so far (Elliot 2005). It is composed of mainly methane and nitrogen and its surface is rocky. It is believed that it is so rock-rich that spontaneous immixing of rock and ice phases in its convectional interior is possible (McKinnon 243). In July 2005 scientists discovered a larger KBO than Pluto. Its size was approximately 10 percent larger than Pluto. It was temporarily named 2003UB13 but later named Eris. Its distance from the sun varies between 38 to 98 AU at a period of 560 years compared to Pluto, which travels from 29 to 49 AU in its orbit. Recent measurements show it to be smaller than Pluto. In 2006, the International Astronomical Union created a new class of objects called dwarf planets because of the discovery of Eris. Pluto, Eris and asteroid Ceres were placed in this category (McKinnon 213).

Haumea

Haumea is an oddly shaped icy object in the Kuiper Belt that was discovered in March 2003 at the Sierra Nevada Observatory in Spain (NASA). It is one of the fastest rotating objects in the Kuiper Belt and takes about 285 earth years to make one revolution around the sun. Its surface is rocky with ice coating. It has two moons Hi’aka and Namaka whose orbital solution indicates they are undergoing through mutual events that will last for next several years (Ragozzine 1).

Plane Nine

Evidence for the existence of a ninth planet in the Kuiper Belt was unveiled in January 2016. It was based on mathematical modeling and computer simulations from research done by astronomers Konstantin Batygin and Mike Brown. It pointed to an object of mass about ten times of the earth, approximately 200 AU distance from the sun at perihelion and an orbital period of 15000 years (Vidmachenko 224). That pronouncement was deemed to be the start of a process that could lead to an exciting discovery by Jim Green, the Director of NASA’s planetary science division. The two astronomers now searching for the object in its predicted orbit using powerful telescopes and have suggested that it will be called planet nine (Batygin 22). Caltech researchers maintained that the planet, traced a bizarre with a highly elongated orbit in the outer solar system. They further maintained it orbits the sun about 20 miles farther from the sun on average than does Neptune.

Conclusion

Despite the fact much information is currently available about the objects in the Kuiper Belt many questions remain unanswered. The optical colors and spectra of the objects always change as they orbit around the sun. They exhibit a wide range of reflected colors relative to the sun from near neutral to very red (Jewitt.2099). There have been questions about the non-uniform orbital distribution of objects in the region and the constraints hey pose on the formation and evolution of the outer solar system. Models and scenarios have been used to explain this, but still outstanding questions still remain such as What is the spatial extend of the Kuiper Belt in terms of its radial and inclination distribution? (Malhotra 16). As telescope technology advances, more information will become available about this intriguing region of the solar system.

Works Cited

Batygin, Konstantin, and Michael E. Brown. “Evidence for a distant giant planet in the solar system.” The Astronomical Journal 151.2 (2016): 22.

Duncan, Martin J., Harold F. Levison, and Stuart Mark Budd. “The dynamical structure of the Kuiper belt.” The Astronomical Journal 110 (1995): 3073.

Elliot, J. L., et al. “The Deep Ecliptic Survey: A search for Kuiper belt objects and Centaurs. II. Dynamical classification, the Kuiper belt plane, and the core population.” The Astronomical Journal 129.2 (2005): 1117.

Jewitt, David C., and Jane X. Luu. “Colors and spectra of Kuiper belt objects.” The Astronomical Journal 122.4 (2001): 2099.

Jewitt, D., J. Luu, and B. G. Marsden. “1992 QB1.” International Astronomical Union Circular 5611 (1992).

Jevvitt, David. “Discovery of the candidate Kuiper belt object 1992 QB1.” Nature 362 (1993).

Keller, H. U. “Comets: Dirty snowballs or icy dirtballs.” Physics and Mechanics of Cometary Materials. Vol. 302. 1989.

Malhotra, Renu, Martin Duncan, and Harold Levison. “Dynamics of the Kuiper belt.” arXiv preprint astro-ph/9901155 (1999).

McKinnon, William B., and Steve Mueller. “Pluto’s structure and composition suggest origin in the solar, not a planetary, nebula.” Nature 335.6187 (1988): 240-243.

Ragozzine, Darin, and Michael E. Brown. “Orbits and masses of the satellites of the dwarf planet Haumea (2003 EL61).” The Astronomical Journal 137.6 (2009): 4766.

Vidmachenko, A. P. “IS THERE 9-TH PLANET IN OUR SOLAR SYSTEM?.” Odessa Astronomical Publications 29 (2016): 224-225.