A NASA Hubble Space Telescope (HS1) image of a tepidly ballooning bubble of gas blasted off a star. The shell surrounds Nova Cygni 1992 which erupted on February 19, 1992. The shell is so young it still contains a record of the initial conditions of the explosion. The HST image was taken in ultraviolet light with the European Space Agency's Faint Object Camera (FOC) on May 31, 1993, 467 days after the explosion. The FOC reveals a remarkably circular yet slightly lumpy ring-like structure. The ring is the edge of the bubble's shell of hot gas. The shell is only 37 billion miles across, or 400 times the diameter of the solar system. A beam of light could cross the shell in less than 2-1/2 days. A striking relic of the explosion is an unusual bar-like structure across the middle of the ring. It might mark the edge-on plane of the orbits of the two members of the binary star system that triggered the nova. An alternative possibility is that the bar is produced by twin jets of gas ejected from the star and spanning the distance between the shell and the star. A nova is a thermonuclear explosion that occurs on the surface of a white dwarf star in a double star system. By knowing the shell's diameter, as calculated from a comparison between its angular size and it expansion velocity (as measured from ground-based observations) astronomers can precisely measure the distance to Nova Cygni, which turns out to be 10,430 light-years. Nova Cygni is located in the summer constellation Cygnus.
Credits
Credit: Francesco Parasce, ESA/STScI and NASA| About The Object | |
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| Object Name | Nova Cygni 1992 |
| R.A. Position | 20h 30m 31.66s |
| Dec. Position | 52° 37' 50.8" |
| About The Object | |
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| 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 |
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| 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. |
