Astronomers using NASA's Hubble Space Telescope have observed for the first time the atmosphere of a planet beyond our solar system evaporating into space.
This artist's illustration shows a dramatic close-up of the scorched extrasolar planet HD 209458b in its orbit only 4 million miles from its yellow, Sun-like star. The planet is a type of extrasolar planet known as a "hot Jupiter."
The planet's outer atmosphere is extended and heated so much by the searing heat from the nearby star that it starts to escape the planet's gravity. This huge envelope of evaporating hydrogen (shown in blue) resembles a comet with a tail trailing behind the planet. Astronomers estimate the amount of hydrogen gas escaping HD 209458b to be at least 10,000 tons per second, but possibly much more. Much of the planet may eventually disappear, leaving only a dense core.
Credits
ESA, Alfred Vidal-Madjar (Institut d'Astrophysique de Paris, CNRS, France) and NASA| About The Object | |
|---|---|
| Object Name | HD 209458, HD 209458b |
| Object Description | Star with Transiting Planet, Jupiter-like Planet with Detected Atmosphere |
| R.A. Position | 22h 03m 10.8s |
| Dec. Position | +18° 53' 04.0'' |
| Constellation | Pegasus |
| Distance | 46 parsecs (150 light-years) |
| Dimensions | Estimated Planet Mass: 0.7 times Jupiter's mass; 220 times the Earth's mass |
| About The Data | |
| Data Description | These data are from the HST archived proposal . The science team is composed of: A. Vidal-Madjar, A. Lecavelier des Etangs and J.-M. Désert (Institut d'Astrophysique de Paris, CNRS, France), G. Ballester (University of Arizona), R. Ferlet and G. Hébrard (Institut d'Astrophysique de Paris, France), and M. Mayor (Geneve Observatory, Switzerland). About HD 209458b: Object Description: Extrasolar Planet Transiting HD 209458; Jupiter-like Planet with Detected Atmosphere Orbital Period: 3.5 days Distance Above Star's Surface: 4 million miles (6.4 million kilometers) Estimated Mass: 0.7 times Jupiter's mass; 220 times the Earth's mass Maximum Temperature: 2000 degrees Fahrenheit (1100 degrees Celsius) |
| Instrument | HST>STIS |
| Exposure Dates | August 11, 2001, September 7, 2001, September 14-15, 2001, and October 30, 2001, Exposure Time: 7 hours |
| Filters | G140M (1150-1700 Å), G430L (2900-5700 Å), E140M (1150-1700 Å) |
| 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. |
