NASA's Hubble Space Telescope captured a detailed image of the tiny galaxy HIPASS J1131–31, nicknamed the "Peekaboo Galaxy," despite its proximity to a bright foreground star. In addition to Hubble imagery, astronomers used the South African Large Telescope (SALT) to collect detailed spectroscopic data on the galaxy's stars, which show it to be one of the least chemically enriched galaxies ever discovered in the local universe.
Typically, generations of stars produce more—and more complex—chemical elements (which astronomers call "metals") over cosmic time. At the dawn of the universe, 13.8 billion years ago, hydrogen and helium were the only abundant elements. Early galaxies that were made up of some of the first generations of stars had not had time to build up much chemical complexity. Evolved galaxies like our own Milky Way have stars that are many billions of years old and are metal-rich, including all the elements that make life on Earth possible. The stars of the Peekaboo Galaxy, however, appear to be only a few billion years old at most. Why, and how, the Peekaboo Galaxy delayed star-formation for so many billions of years is a question that astronomers will continue to investigate.
Credits
Science
NASA, ESA, Igor Karachentsev (SAO RAS)
Image Processing
Alyssa Pagan (STScI)
| About The Object | |
|---|---|
| Object Name | HIPASS J1131–31 |
| Object Description | Dwarf galaxy |
| R.A. Position | 11:31:35.2 |
| Dec. Position | -31:40:20 |
| Constellation | Hydra |
| Distance | About 22 million light-years (~6.8 Mpcs) |
| Dimensions | Image is approximately 3 arcminutes across (20,000 lys) |
| About The Data | |
| Data Description | This image was created from Hubble data from proposal: (R. B. Tully) |
| Instrument | ACS/WFC |
| Exposure Dates | 14 July 2020 |
| Filters | F606W, F814W |
| About The Image | |
| Color Info | These images are a composite of separate exposures acquired by the Hubble Space Telescope using the ACS/WFC instrument. Several filters were used to sample different 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: Cyan: F606W, Orange: F814W |
| 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. |
