以表彰他们发现海王星以外物体及描述其特性，对研究太阳系最初之形成及追寻短周期彗星来源提供寳贵资料。
朱维特(Jewitt) 和刘(Luu) 在1993 年发现海王星以外物体。在此之前，人们对太阳系远处，在海王星轨道至奥特云(Oort cloud) 之间的空间，所知甚少。(海王星离太阳30天文单位，而奥特云则离开太阳超过一万天文单位，为长周期彗星之源。) 例如，在这个区域到底有些甚么物体？从朱维特和刘的硏究，我们现在得知，在30至50天文单位之间的区域，充满了数以万计的冰冻物体，直径超出50公里。这些物体因吸积而汇集，吸积过程属於行星形成的早期。但受到某些现在尚未确定的过程影响，它们的速度分布增濶，以至吸积过程终止。其后，由於它们互相远离，很少发生碰撞，因而没有进一步的演变。所以这些物体为我们提供了最佳的记录，让我们可以了解行星形成过程中早期的情况。
这搜索与研究直至发现第一颗海王星外物体，是历时五年努力的成果。在进行搜索的初期，朱维特为麻省理工学院教授，而刘为他的研究生。
Astronomy is arguably the oldest science. Observations of the motion of heavenly bodies date back more than 2,500 years. Nevertheless, as recently as 1992, immediately prior to the detection of the first Kuiper belt objects (KBOs) by Jewitt and Luu,1 little was known about the contents of the solar system beyond 30 AU.2 Distant bodies are dim because they reflect little sunlight back to Earth and our most powerful telescopes can only image small angular regions at a single pointing. Thus searches for widely-spaced, faint images are tedious and resource intensive. Before Jewitt and Luu’s discovery, Pluto and its large satellite Charon were the only directly detected bodies orbiting beyond Neptune.
Comets provide indirect information about reservoirs of bodies beyond 30 AU. Although comets are directly detected only when they come within a few AU, their orbits can be traced back to show where they came from. By 1950 it had been established that most long-period comets were visitors from distances in excess of 10,000 AU and that their orbits were randomly oriented with respect to the mean orbit plane of the solar system. These facts led Jan Oort to hypothesize that comets are stored in an enormous spherical cloud beyond 10,000 AU and that gravitational deflections by nearby stars are responsible for injecting those we detect into the inner solar system. Oort’s model is widely accepted and the hypothetical comet cloud carries his name. However, his assumption that short-period comets are descendants of long-period ones did not fare as well.
