because both orbit close to the Solar System's gas giants. Possible Hills cloud objects Bodies in the Hills cloud are made mostly of water ice, methane and ammonia. Astronomers suspect many long-period comets originate from the Hills cloud, such as Comet Hyakutake. In their article announcing the discovery of Sedna, Mike Brown and his colleagues asserted that they observed the first Oort cloud object. They observed that, unlike scattered disc objects like Eris, Sedna's perihelion (76 AU) was too remote for the gravitational influence of Neptune to have played a role in its evolution. The authors regarded Sedna as an "inner Oort cloud object", located along the Ecliptic and placed between the Kuiper belt and the more spherical part of the Oort cloud. However, Sedna is much closer to the Sun than expected for objects in the Hills cloud and its inclination is close to that of the planets and the Kuiper belt. Considerable mystery surrounds , with its retrograde orbit that could make it originate from the Hills cloud or perhaps the Oort cloud. The same goes for damocloids, whose origins are doubtful, such as the namesake for this category, 5335 Damocles. Comets Astronomers suspect that several comets come from the same region as the Hills cloud; in particular, they focus on those with aphelia greater than 1,000 AU (which are thus from a farther region than the Kuiper belt), but less than 10,000 AU (or they would otherwise be too close to the outer Oort cloud). Some famous comets reach great distances and are candidates for Hills cloud objects. For example, Comet Lovejoy, discovered on 15 March 2007 by Australian astronomer Terry Lovejoy, had an inbound aphelion distance of around 1,800 AU. Comet Hyakutake, discovered in 1996 by amateur astronomer Yuji Hyakutake, has an outbound aphelion of 3,500 AU. Comet McNaught, discovered on 7 August 2006 in Australia by Robert H. McNaught, became one of the brightest comets of recent decades, with an aphelion of 4,100 AU. Comet Machholz, discovered on 27 August 2004 by amateur astronomer Donald Machholz, came from about 5,000 AU. Sedna, the first candidate Sedna is a minor planet discovered by Michael E. Brown, Chad Trujillo and David L. Rabinowitz on 14 November 2003. Spectroscopic measures show that its surface composition is similar to that of other trans-Neptunian objects: It is mainly composed of a mixture of water ices, methane, and nitrogen with tholins.