With the help of NASA's Hubble Space Telescope, astronomers have determined that 2002 LM60, an icy Kuiper belt object dubbed "Quaoar," by its discoverers, is the largest body found in the solar system since the discovery of Pluto 72 years ago. Quaoar (pronounced kwa-whar) is about half the size of Pluto. Like Pluto, Quaoar dwells in the Kuiper belt, an icy debris field of comet-like bodies extending 7 billion miles beyond Neptune's orbit.
The photograph at bottom right, taken by Hubble's Advanced Camera for Surveys, is a close-up view of the icy world. Only Hubble's sharp vision can resolve the disk of this distant world, leading to the first-ever direct measurement of the true size of a Kuiper belt object. Quaoar's diameter is about 800 miles (1300 kilometers). It is the farthest object in the solar system ever to be resolved by a telescope. The Hubble photo does not show details of Quaoar's icy surface because the object is too far away. Quaoar is about 4 billion miles (6.5 billion kilometers) from Earth, more than 1 billion miles farther than Pluto. The photograph was made by assembling 16 pictures of the object. Observations were made July 5, 2002 and Aug. 1, 2002.
The image at upper right is a composite of 16 snapshots of the object as it traveled across the sky. Quaoar is in a circular orbit around the Sun. The snapshots were taken over a 29- minute span on July 5.
The photograph at left, part of the Digitized Sky Survey, shows the Kuiper belt object's approximate path across the summer constellation Ophiuchus. The small box in the center defines Hubble's narrow view, an area devoid of stars.
Credits
NASA and Michael Brown (Caltech, Pasadena, CA)| About The Object | |
|---|---|
| Object Name | 2002 LM60, Quaoar |
| Object Description | Kuiper Belt Object |
| R.A. Position | 16h 36m 18s |
| Dec. Position | -14° 48' 0" |
| Constellation | Ophiuchus |
| Distance | About 43 astronomical units (about 4 billion miles or 6.5 billion kilometers) |
| Dimensions | Approximately 800 miles in diameter (about 1300 kilometers) |
| About The Data | |
| Data Description | Principal Astronomers: M. Brown and C. Trujillo (Caltech) |
| Instrument | DSS (left), ACS/HRC (top right), and HST>ACS (bottom right) |
| Exposure Dates | July 5, 2002 (HRC), July 5, 2002 and August 1, 2002 (ACS) |
| About The Object | |
|---|---|
| Object Name | A name or catalog number that astronomers use to identify an astronomical object. |
| Object Description | The type of astronomical object. |
| R.A. Position | Right ascension – analogous to longitude – is one component of an object's position. |
| Dec. Position | Declination – analogous to latitude – is one component of an object's position. |
| Constellation | One of 88 recognized regions of the celestial sphere in which the object appears. |
| Distance | The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs. |
| Dimensions | The physical size of the object or the apparent angle it subtends on the sky. |
| About The Data | |
| Data Description |
|
| Instrument | The science instrument used to produce the data. |
| Exposure Dates | The date(s) that the telescope made its observations and the total exposure time. |
| Filters | The camera filters that were used in the science observations. |
| About The Image | |
| Image Credit | The primary individuals and institutions responsible for the content. |
| Publication Date | The date and time the release content became public. |
| Color Info | A brief description of the methods used to convert telescope data into the color image being presented. |
| Orientation | The rotation of the image on the sky with respect to the north pole of the celestial sphere. |
