IC 1396 in the constellation Cepheus imaged in the red light from hydrogen atoms. This image was obtained as part of the
INT/WFC Photometric Hydrogen-Alpha Survey of the Northern Galactic Plane (IPHAS). Credit: Geert Barentsen & Jorick Vink (Armagh Observatory) & the IPHAS Collaboration.
[ JPEG | TIFF ].
IC1396, also called the Elephant's Trunk Nebula, is one of the largest emission nebulae in the Northern Sky with a diameter of 3 degrees. It is a giant cloud of gas and dust at a distance of 2400 light years from Earth. It is illuminated by the massive O-type star HD 206267 in the centre. Radiation and winds from this hot star are thought to compress parts of the cloud and trigger star formation.
The mosaic shown here was assembled from ~400 exposures taken in the H-alpha, Sloan r' and Sloan i' bands using the Wide Field Camera (WFC) on the 2.5m Isaac Newton Telescope (INT). The data were taken by multiple observers between 2004 and 2009 as part of the INT/WFC Photometric Halpha Survey of the Northern Galactic Plane (IPHAS). The mosaic was created using the
Montage toolkit maintained by NASA/IPAC. Saturation spikes and artefacts have been removed by hand.
Photometric analysis of this data revealed more than 100 previously unknown pre-main sequence stars which are still
accreting material from a circumstellar disk (Barentsen et al. 2011).
References and more information:
- Barentsen G.; Vink J.; Drew J. E.; Greimel R.; Wright N. J., Drake J. J., Martin E. L., Valdivielso L., Corradi R. L. M., 2011, "T Tauri candidates and accretion rates using IPHAS: method and application to IC1396", MNRAS, 415, 103.
- INT/WFC Photometric Halpha Survey of the Northern Galactic Plane: http://www.iphas.org.
- Montage toolkit: http://montage.ipac.caltech.edu.