This nebula is a dark dust cloud located in the "sword" of that constellation. While it's very difficult to detect with backyard telescopes, it is iconic due to its picturesque shape that photographs of it have been gracing astronomy books and other publications for decades.
The recent image in question was taken by the Hubble Space Telescope and has just been released in honor of the 23rd anniversary of the deployment of that instrument.
These past couple of weeks have also seen the announcement of the discoveries of three planets, all of which are only slightly larger than Earth, orbiting within the "habitable zones" (i.e., those regions where the temperatures are such that water can exist in its liquid state) of their respective parent stars (two of these planets orbit the same star). These worlds were found by the Kepler spacecraft, which was launched four years ago for this very purpose.
Meanwhile, late last month came the announcement that the Alpha Magnetic Spectrometer experiment aboard the International Space Station has detected signals that might originate from the so-called "dark matter" that is known to permeate the universe but about which almost nothing is known.
The common thread running through these announcements is that they all resulted from astronomical telescopes in space.
Another very important advantage of a space-based telescope is due to the fact that the atmosphere blocks out many forms of light from reaching the surface. For those of us who live on the surface, this is good news since many of these forms of light ultraviolet and x-rays are of high energy and would be very harmful, indeed fatal, were we to be exposed to them to any significant degree.
However, our inability to detect these various forms of light from the surface greatly restricts our view of the outside universe and thus prevents us from gaining much of a complete understanding of it.
What could, perhaps, be considered the first reasonably successful attempts to conduct astronomy from space took place during the late 1940s, with the placing of ultraviolet detectors aboard rockets launched from, among other places, what was then called White Sands Proving Ground.
Once satellites were launched, one of the earliest astronomically oriented satellites were those of the Orbiting Solar Observatory series, the first of which was launched in 1962. As this name implies, these satellites were primarily intended to study the sun, utilizing instruments sensitive to ultraviolet and to x-rays.
The satellites of the Orbiting Astronomical Observatory series, the first successful one of which was launched in 1968 and which primarily focused on the ultraviolet part of the spectrum, can be considered the first orbiting space telescopes. In the years and decades that followed, more and more orbiting space telescopes began to be launched, with these exploring various parts of the spectrum all the way from the short-wavelength, high-energy x-rays and gamma-rays, to the long-wavelength, low-energy radio waves.
The opening up of all these "windows" to the universe has greatly increased our knowledge in a way that was inconceivable prior to the beginning of the Space Age.
Today, numerous space observatories are actively studying the universe. Some of these, like Hubble (which operates primarily in "visible light," but also slighty into both the infrared and the ultraviolet) can be considered "general purpose" telescopes. They are capable of conducting a variety of astronomical investigations.
There are also several "special purpose" telescopes, for example the aforementioned Kepler mission (which also operates in "visible light") designed to search for planets orbiting other stars, as well as the aforementioned AMS experiment (a particle-detection instrument) that is designed to look for signs of "dark matter."
Other examples include the European Space Agency's Planck mission, which operates in the microwave part of the spectrum and is designed to study the "Cosmic Microwave Background radiation" that resulted from the Big Bang, and NASA's Swift mission which is designed to detect the mysterious gamma-ray bursts and then rapidly determine their positions with ultraviolet and "visible light" telescopes.
And, certainly, there are more to come. The future space observatory receiving the most attention is the James Webb Space Telescope, a "general purpose" instrument often touted as the successor to Hubble (and with a mirror 2 1Ú2 times the size of that of Hubble), although Webb will primarily be studying the sky in the infrared. It is currently scheduled to be launched around 2018.
Meanwhile, several other "special purpose" space telescopes are currently being built, with others being proposed and designed. While not all of these will eventually end up being launched, there will nevertheless be enough such that our knowledge of the surrounding universe will continue to increase enormously.