Picture of the Month for 2025

• March 2025 - Picture of the Month

  Open cluster RCW 38 in Vela

  

  RCW 38 lies about 5,500 light-years away in the direction of Vela. It comprises a large and young open star cluster embedded within a nebula of dust and gas from which it formed, probably less than a million years ago. There are thousands of stars in this cluster, of which about 20 are huge O-type stars destined to become supernovae, and most of them are hidden within the nebula.

  I'm guessing that you've probably spotted that this isn't an amateur image, but I have my reasons.

  The European Southern Observatory (ESO) have captured a visible light image of RCW 38 in the past, but I've chosen this one because it was release last month and, most importantly, it's in the infrared so we can see far more stars in this wide field of view. If you'd like to compare the visible and infrared view then ESO have a fantastic slider on their website.

  Of course if it's the stars of RCW 38 itself that you're particularly interested in seeing, then ESO pointed another of their instruments, the HAWK-I camera, at this target for a close look a few years ago.

  

  So I've really got two Pictures of the Month and both are in the infrared spectrum, which is outside of the amateur sphere, at least I think that it is.

  James Whinfrey - Website Administrator.

• Interacting galaxies NGC 2207 and IC 2163 in Canis Major

  February 2025 - Picture of the Month

  

  Unfortunately I didn't manage to get permission to use the image I'd originally hoped to feature, perhaps that object will appear another time. But this image of a pair of merging galaxies from the James Webb Space Telescope (JWST) using its mid-infrared MIRI instrument isn't a bad alternative, is it?

  The Hubble Space Telescope (HST) has previously imaged NGC 2207 and IC 2163 with wonderful results, but this infrared image strips away the obscuring layers of dust and gas to reveal the extent of the star formation in these two galaxies. I think that this lends this image a skeletal feel around the galactic cores, especially when compared with the outrageously colourful HST version.

  It's my understanding that the "senior" partner here is NGC 2207 on the right, and also in the foreground, which has just started the process of stripping the gas from IC 2163 in the upper left. The JWST image above shows the position of bright new star clusters in both galaxies, one of the brightest of which is a starburst region in the lower right, on the end of the outer arm of NGC 2207. Much of this activity has been stimulated by IC 2163's first pass in this merger which is taking place about 114 million light-years away. As a result these galaxies have provided seven supernovae since 1975, five of which have been recorded this century.

  Naturally the HST and JWST images have been combined to provide a highly detailed view of the scene. I particularly enjoyed the "slider" that provides a much better comparison of the action.

  James Whinfrey - Website Administrator.

• January 2025 - Picture of the Month

  Spiral Galaxy IC 342 in Camelopardalis

  

  I thought that it was about time I featured a galaxy, and as luck would have it Capella Observatory have just captured this image of the spectacular IC 342.

  I'm not going to say much about this galaxy because Owen Brazell's already featured it as his Galaxy of the Month way back in September 2012, so you should check out that article.

  As Owen mentions, this galaxy is highly obscured by the gas and dust in our own Milky Way, and in his article he linked to an infrared image of IC 342 taken by WISE pondering how spectacular it might look if where not obscured. In 2012 we didn't have ESA's Euclid near-infrared telescope which captured its own image of IC 342 back in 2023. A great improvement on WISE showing many fainter and bluer star that are the key to studying star formation.

  However this amateur image shows a great deal of structural detail. For example many of the larger star clusters in IC 342 that Euclid observed can clearly be seen here too, especially on Capella's larger version. What I find noticeable in examining the two images is perhaps unsurprising: Euclid shows the spiral arm structure more clearly, but the Capella image makes those dust lanes visible. That's the value of examining objects in multiple wavelengths of light I suppose.

  No doubt that IC 342 is more of an imaging target, perhaps try for those globular clusters, but it is accessible to the visual observer that likes a challenge.

  James Whinfrey - Website Administrator.