This sequence of images taken by NASA's Hubble Space Telescope shows Comet 252P/LINEAR as it passed by Earth. The visit was one of the closest encounters between a comet and our planet.
The images were taken on April 4, 2016, roughly two weeks after the icy visitor made its closest approach to Earth on March 21. The comet traveled within 3.3 million miles of Earth, or about 14 times the distance between our planet and the moon. These observations also represent the closest celestial object Hubble has observed, other than the moon.
The images reveal a narrow, well-defined jet of dust ejected by the comet's icy, fragile nucleus. The nucleus is too small for Hubble to resolve. Astronomers estimate that it is less than one mile across. A comet produces jets of material as it travels close to the sun in its orbit. Sunlight warms ices in a comet's nucleus, resulting in large amounts of dust and gas being ejected, sometimes in the form of jets. The jet in the Hubble images is illuminated by sunlight.
The jet also appears to change direction in the images, which is evidence that the comet's nucleus is spinning. The spinning nucleus makes the jet appear to rotate like the water jet from a rotating lawn sprinkler. The images underscore the dynamics and volatility of a comet's fragile nucleus.
Comet 252P/LINEAR is traveling away from Earth and the sun; its orbit will bring it back to the inner solar system in 2021, but not anywhere close to Earth.
These visible-light images were taken with Hubble's Wide Field Camera 3.
Credits
NASA, ESA, and J.-Y. Li (Planetary Science Institute)| About The Object | |
|---|---|
| Object Name | Comet 252P/LINEAR |
| Object Description | Comet |
| Distance | At the time of the Hubble observations on April 4, 2016, Comet 252P/LINEAR was 0.093 astronomical unit (8.6 million miles or 14 million kilometers) from Earth. The sun-comet distance on that date was 1.037 astronomical units (96 million miles or 155 million kilometers). At closest approach on March 21, 2016, the comet was 0.036 astronomical unit (3.3 million miles or 5.4 million kilometers) from Earth. |
| About The Data | |
| Data Description | The images were created from Hubble data from proposal : J.-Y. Li and N. Samarasinha (Planetary Science Institute), M. Kelley (University of Maryland), M. Mutchler (STScI), and D. Farnocchia (Jet Propulsion Laboratory). |
| Instrument | HST>WFC3/UVIS |
| Exposure Dates | April 4, 2016 |
| Filters | F625W (SDSS r) |
| About The Image | |
| Color Info | This image was originally black and white and recorded only overall brightness. These brightness values were translated into a range of bluish hues. Such color "maps" can be useful in helping to distinguish subtly varying brightness in an image. |
| Compass Image |  |
| 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. |
