Podcast: Swift Sees Andromeda in a New Light
- By Maggie Masetti
- September 16, 2009
- 2 Comments
Click to listen! (6.3MB MP3, right-click to save)
Transcript (Text, PDF)
There’s more to the universe than meets the eye – or at least our eyes, which can only detect the visible part of the electromagnetic spectrum. We can see just a small fraction of the light emitted by the universe. This is why we have satellites that can observe different parts of the electromagnetic spectrum – they each provide us a different piece of the puzzle.
Scientist Dr. Stefan Immler was part of a team that captured a new and unique view of one of our closest galactic neighbors with the Swift satellite, which has the ability to detect ultraviolet light. The Andromeda Galaxy, or M31, is a beautiful “nearby” spiral galaxy that is actually visible to the naked eye. We talked with Dr. Immler about what his team learned about the galaxy when Swift took a look in the UV.
About the Episode
Dr. Stefan Immler is a research scientist on the Swift team at NASA’s Goddard Spaceflight Center. His team produced a mosaic of M31 which was made from merging 330 individual images taken by the Ultraviolet/Optical Telescope aboard NASA’s Swift spacecraft. It is the highest-resolution image of the galaxy ever recorded in the ultraviolet. The image shows a region 200,000 light-years wide and 100,000 light-years high. You can see this amazing image in the press release below:
Here are some other links that might be of interest:
- Want to know more about UV light? Read Imagine the Universe! on The Electromagnetic Spectrum.
- More about the Swift Satellite
- Swift Education & Public Outreach.
- Where to find the Andromeda Galaxy in the sky.
| Host | Maggie Masetti |
| Interviewer | Tommy Nelson |
| Guest | Stefan Immler |
| Editor | Tommy Nelson Maggie Masetti |
| Theme Music | Naked Singularity |
| Additional Music | Kevin McCloud |
| Transcript | Eric Winter Maggie Masetti |
| Website Support | Meredith Gibb Maggie Masetti |
| Producer | Sara Mitchell |
| Executive Producer | Anita Krishnamurthi |
| Responsible NASA Official | Kim Weaver |
This uv image is presented in today’s (October 27, 2010) Astronomy Picture Of the Day (APOD). There is a bright object directly to the right of M31’s satellite galaxy M32 in both the uv image and the accompanying visible light image. In the visible image, the bright object is surrounded by what appears to be an elliptical dark halo or zone of clearing with long and short axes about 5X and 3X the diameter of the bright object. In the UV image, the dark halo/zone of clearing is now a bright, diffuse purple halo. The bright main object is in the same location but appears to have about a 1/4 larger diameter. In addition, there is a very strange looking object (or more exactly, a closely interacting set of 3 or more objects) that is positioned closer to the opposite focus of the ellipse, and is surrounded with its own dark halo or zone of clearing. Each member of the set of three interacting objects is somewhat torus-like in appearance, with a dark center and bright ring surrounding it.
What is this object or set of objects?
Also, APOD 2008 Jan 24 image of M31 appears to show a substantial second satellite galaxy on the back side of M31 and to the left of M31’s nucleus. There is no trace of that satellite galaxy on today’s APOD visual image of M31, and no hint of it on the UV image either.
So who took the other satellite galaxy, and what did they do with it?
David – Good questions! It’s always interesting (and somewhat difficult) to compare images of objects taken in different wavelengths, as each wavelength is picking up different aspects of the object (gas, dust, energetic areas, etc.). I don’t have answers to your questions, but perhaps it’s something that we can ask around about… and perhaps cover in a future feature!