Photographs of the Sombrero Galaxy Employing Visible, Infrared, and X-radiation

The Sombrero galaxy, M104, is named for its resemblance to a Mexican sombrero or hat. The Sombrero is one of the largest galaxies in the Virgo cluster and is located some 28 million light-years distant. It is actually a spiral galaxy, so it only resembles a hat because we see it edge-on. Actually, we do not actually obtain a complete picture of the galaxy using optical light only. This is because high-energy emitting objects give off infrared, ultraviolet, and/or x-ray "light" frequencies in addition. The amounts of each frequency range vary with different features of a single object, so images taken using different wavelengths captures different features.

Viewing the Sombrero Galaxy in Visible Light

The Sombrero galaxy has been photographed in visible light by the Hubble telescope. Seen here in the lower left, is a visible light only image of the Sombrero galaxy, taken with the Hubble telescope. Notice the large bowl of bright light in the center of the galaxy and the dark rim of dust at its edge or "brim." It appears dark because it emits considerably less visible light than the rest of the galaxy.

The Sombrero Galaxy in Infrared

Infrared light is light of a lower frequency than visible light. Such objects may highlight details not seen intensely in either x-ray or visible light. The reader may be familiar with the use of infrared photography at night to reveal the warm bodies of escaped criminals. Human bodies do not give off visible light, but they do give off infrared or heat radiation.

Notice in the lower right-hand part of this image, the Sombrero galaxy using the Spitzer infrared telescope. What was only a dark edge in visible light is now revealed in detail in the infrared region. Besides that, this Spitzer image demonstrates the outer disk is warped. Warping often indicates gravitational interaction with other galaxies. Also, zooming in reveals the Sombrero galaxy has an inner ring of stars, as well as an object at its center believed to be an immense black hole.

The Sombrero Galaxy in X-Rays

In x-ray light, the bowl portion of the Sombrero galaxy extends some 60,000 light years across, but appears subdued in comparison with the optical image. This is because x-ray emission is less intense, due to the much higher energies required to produce it. This is a good thing, as it enables the revealing of point sources of x-ray emission within the galaxy that would otherwise be overpowered. Notice the spiral portion of the galaxy is missing in this image taken by Chandra telescope of the Sombrero galaxy. This is because the spiral feature emanates essentially no x-rays.

In Conclusion

An accurate concept of the Sombrero galaxy is best achieved by considering data from as much of the complete electromagnetic spectrum as possible. In fact, combining the Spitzer infrared image with a view taken by the Hubble telescope results in the hauntingly beautiful image seen here. Such efforts reveal why multiple space explorations may be required to gain an accurate and complete understanding of any high-energy radiating space object.

References and Resources:

M104 indicates the Sombrero galaxy is Object number 104, of Messier's catalog. For further information, see The Messier Catalog of Deep Sky Objects.

Caltech Institute, Spitzer Science Center - Spitzer and Hubble View of the Sombrero Galaxy

European Southern Observatory - The Sombrero Galaxy

Microsoft's Worldwide Telescope - "A Tour of the Sombrero Galaxy," by Megan Watzke, Chandra's X-ray Observatory.