14 DAY TRIAL // Astronomers at the American space agency say that they've recently used the Stratospheric Observatory for Infrared Astronomy (SOFIA) aircraft to conduct a series of scientific observations on the nature of the stellar nursery W40. This is one of the largest such structures in the entire galaxy.
The massive star-forming region is producing new stellar objects at a frantic pace, experts say, which makes it a prime target for astronomical observations. SOFIA collected data of the object in the mid-infrared portion of the electromagnetic spectrum.
The data it produced were put together in the highest-resolution IR image the object ever created. The primary instrument for this observations sessions was the Faint Object infraRed Camera for the SOFIA Telescope (FORCAST).
NASA explains that the telescope aboard the heavily-modified Boeing 747SP airliner has a diameter of 2.5 meter (100 inches), making it extremely sensitive to IR wavelengths. The main reason why SOFIA was built in the first place is that it can fly above the clouds.
This in turn gives it the ability to conduct studies over areas of the planet where constructing ground-based telescopes is not feasible due to prevailing weather conditions. The airborne observatory may even fly above polar regions, provided it has a nearby base of operations.
NASA experts say that the new image of W40 was taken at wavelengths of 5.4, 24.2 and 34.8 microns. The reason why these particular wavelengths were selected is that they are usually blocked by water vapors in Earth's atmosphere.
In addition, only IR observations can penetrate through to the stellar nursery's location. It is located beyond a massive, thick cloud of molecular hydrogen gas and cosmic dust, which makes it invisible to telescopes operating in visible-light wavelengths.
The recent observations revealed a very bright nebula within the star-forming region. Additionally, SOFIA identified numerous young, blue stars, alongside several massive ones. The latter tipped the scales at between 6 and 20 solar masses.
“At least 50 percent of the stars in the Milky Way Galaxy formed in massive clusters of thousands of stars similar to W40. Evidence suggests that the solar system developed in such a cluster almost 5 billion years ago,” a NASA press release explains.
“Because stars are relatively dim at the wavelengths measured by FORCAST, the observed emission in the images is due to dust surrounding the stars that is heated to a few hundred degrees,” the statement goes on to say.