This festive NASA Hubble Space Telescope image resembles a holiday wreath made of sparkling lights. The bright southern hemisphere star RS Puppis, at the center of the image, is swaddled in a gossamer cocoon of reflective dust illuminated by the glittering star. The super star is ten times more massive than our Sun and 200 times larger.
RS Puppis rhythmically brightens and dims over a six-week cycle. It is one of the most luminous in the class of so-called Cepheid variable stars. Its average intrinsic brightness is 15,000 times greater than our Sun's luminosity.
The nebula flickers in brightness as pulses of light from the Cepheid propagate outwards. Hubble took a series of photos of light flashes rippling across the nebula in a phenomenon known as a "light echo." Even though light travels through space fast enough to span the gap between Earth and the Moon in a little over a second, the nebula is so large that reflected light can actually be photographed traversing the nebula.
By observing the fluctuation of light in RS Puppis itself, as well as recording the faint reflections of light pulses moving across the nebula, astronomers are able to measure these light echoes and pin down a very accurate distance. The distance to RS Puppis has been narrowed down to 6,500 light-years (with a margin of error of only one percent).
Credits
NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration;Acknowledgment: H. Bond (STScI and Pennsylvania State University)
| About The Object | |
|---|---|
| Object Name | RS Puppis |
| Object Description | Cepheid Variable |
| R.A. Position | 08h 13m 04s.22 |
| Dec. Position | -34° 34' 42".70 |
| Constellation | Puppis |
| Distance | 6,500 light-years (2,000 parsecs) |
| About The Data | |
| Data Description | ACS/WFC data of RS Puppis were obtained as part of the HST proposal : H. Bond (STScI and Pennsylvania State University), W. Sparks (STScI), P. Kervella (Observatoire de Paris), A. Merand (European Southern Observatory), D. Bersier (Liverpool John Moores University), P. Fouque (Observatoire Midi-Pyrenees), E. Pompei (European Southern Observatory), G. Perrin (Observatoire de Paris), and V. Scowcroft (Carnegie Institution of Washington) |
| Instrument | HST>ACS/WFC |
| Exposure Dates | March 26, 2010, Exposure Time: 35 minutes |
| Filters | F435W (B) and F606W (V) |
| About The Image | |
| Color Info | This image is a composite of separate exposures acquired by the ACS instrument on the Hubble Space Telescope (HST). Several filters were used to sample broad wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: Blue: F435W (B) Green: F435W (B) + F606W (V) Red: F606W (V) |
| 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. |
