This NASA Hubble Space Telescope view of the nearby barred spiral galaxy NGC 1672 unveils details in the galaxy's star-forming clouds and dark bands of interstellar dust.
One of the most striking features is the dust lanes that extend away from the nucleus and follow the inner edges of the galaxy's spiral arms. Clusters of hot young blue stars form along the spiral arms and ionize surrounding clouds of hydrogen gas that glow red. Delicate curtains of dust partially obscure and redden the light of the stars behind them by scattering blue light.
Galaxies lying behind NGC 1672 give the illusion they are embedded in the foreground galaxy, even though they are really much farther away. They also appear reddened as they shine through NGC 1672's dust. A few bright foreground stars inside our own Milky Way Galaxy appear in the image as bright and diamond-like objects.
As a prototypical barred spiral galaxy, NGC 1672 differs from normal spiral galaxies, in that the arms do not twist all the way into the center. Instead, they are attached to the two ends of a straight bar of stars enclosing the nucleus. Viewed nearly face on, NGC 1672 shows intense star formation regions especially off in the ends of its central bar.
Astronomers believe that barred spirals have a unique mechanism that channels gas from the disk inward towards the nucleus. This allows the bar portion of the galaxy to serve as an area of new star generation.
NGC 1672 is also classified as a Seyfert galaxy. Seyferts are a subset of galaxies with active nuclei. The energy output of these nuclei can sometimes outshine their host galaxies. This activity is powered by accretion onto supermassive black holes.
NGC 1672 is more than 60 million light-years away in the direction of the southern constellation Dorado. These observations of NGC 1672 were taken with Hubble's Advanced Camera for Surveys in August of 2005. The composite image was made by using filters that isolate light from the blue, green, and infrared portions of the spectrum, as well as emission from ionized hydrogen.
Credits
NASA, ESA, and The Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration| About The Object | |
|---|---|
| Object Name | NGC 1672 |
| Object Description | Barred Spiral Galaxy |
| R.A. Position | 04h 45m 42s.10 |
| Dec. Position | -59° 14' 56" |
| Constellation | Dorado |
| Distance | Approximately 60 million light-years (18 megaparsecs) away. |
| Dimensions | This image is 4.4 arcminutes (75,000 light-years or 23 kiloparsecs) wide. |
| About The Data | |
| Data Description | The Hubble image was created from HST data from proposal : L. Jenkins (University of Leicester), M. Ward and T. Roberts (University of Durham), A. Levan (University of Hertfordshire), and A. Zezas (Harvard- Smithsonian Center for Astrophysics). |
| Instrument | HST>ACS/WFC |
| Exposure Dates | August 1, 2005, Exposure Time: 2.7 hours |
| Filters | F435W (B), F550M (y), F658N (Halpha+[N II]), and F814W (I) |
| About The Image | |
| Color Info | This image is a composite of many separate exposures made by the ACS instrument on the Hubble Space Telescope using several different filters. Three filters were used to sample broad wavelength ranges. One filter was used to sample narrow wavelength emission. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are: Blue: F435W (B) Green: F550M (y) Red: F658N (Halpha+[N II]) + F814W (I) |
| 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. |
