As the universe evolves, density fluctuations in the intergalactic gas (hydrogen and helium) grow into clumps and filaments under gravity's pull. The densest clumps form galaxies and quasars whose radiation energizes (ionizes) the remaining intergalactic gas.
Observations using NASA's Far Ultraviolet Spectroscopic Explorer (FUSE) reveal the structure of ionized helium that traces the lowest density regions of the intergalactic medium.
Credits
Illustration
Ann Feild (STScI), Frank Summers (STScI), Gerard Kriss (STScI)
| About The Data | |
|---|---|
| Data Description | Technical facts about this news release: Principal Astronomers: G. A. Kriss (STScI/JHU), J. M. Shull (U. Colorado), W. Oegerle (GSFC), W. Zheng (JHU), A. F. Davidsen (JHU), A. Songaila (U. Hawaii), J. Tumlinson (U. Colorado), L. L. Cowie (U. Hawaii), J.-M. Deharveng (Laboratorie d'Astronomie Spatiale, France), S. D. Friedman (JHU), M. L. Giroux (U. Colorado), R. F. Green (KPNO/NOAO), J. B. Hutchings (Herzberg Inst. of Astrophysics,Canada), E. B. Jenkins (Princeton U. Obs.), J. W. Kruk (JHU), H. W. Moos (JHU), D. C. Morton (Herzberg Inst. of Astrophysics/Canada), K. R. Sembach (JHU), T. M. Tripp (Princeton U. Obs.) About this Object: Object Name: HE2347-4342 Object Description: Quasar R.A.: 23h 50m 34.24s Dec.: -43° 26' 00.0" Constellation: Phoenix Distance: 3,070 Mpc (10 billion light-years). Redshift: Z2.885 Magnitude: V16.1 About the Data: Instrument: HST–STIS, HST–FUSE Exposure Dates: August 21, 2000 and October 16, 2000, Exposure Time: 55 minutes (STIS); August 17 - 27, 2000, and October 11- 21, 2001, Exposure Time: 105 hours (FUSE) |
| 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 |
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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. |
