NASA's Retired Spitzer Space Telescope Shows Us Where Stars Are Born
Aug 31, 2020,05:23pm EDT
Kiona N. Smith Contributor
The green area on the left side of the nebula is younger than the red cloud on the right in this false-color image. NASA
NASA’s Spitzer Space Telescope retired earlier this year, but for astronomers, the mission isn’t over yet. They’re still studying a wealth of astronomical data, which the telescope collected and sent home faster than a full staff of humans and computers could analyze it. Researchers working through the data Spitzer left behind recently unearthed a detailed image of a nebula where some of the most massive stars in the galaxy are spawned.
If you could see the nebula W51, it would stretch across a patch of night sky about as wide as the full Moon – despite being 17,000 light years away. The Moon looms so large in our night sky because it’s so close: about 1.25 light seconds. W51, if it were visible in the wavelengths of light our eyes can see, would loom just as large because it’s actually enormous, even in cosmic terms: about 350 light years wide, encompassing dozens of stars.
But you can’t see W51, and neither can telescopes that see the universe in the same wavelengths of light as your human eyes. Physicists call this the visible spectrum, which is definitely going to confuse any alien species we eventually meet who can see in ultraviolet or infrared (which is pretty plausible; several Earth species do it). Unfortunately, other dust clouds in the 17,000 light years of interstellar space between us and W51 block the visible light from the nebula. Radiation with longer wavelengths, like infrared and radio waves, can penetrate those interstellar dust clouds – which is how astronomers with radio telescopes discovered W51 in 1958, and how Spitzer observed the nebula’s infrared radiation in awesome detail, revealing a cosmic wonder that would otherwise be invisible to us.
“The really spectacular images provided by Spitzer via the GLIMPSE survey – in concert with data from many other, complementary telescopes – give us insight into how massive stars form in our Milky Way and then how their powerful winds and radiation interact with the remaining ambient material,” said California State Polytechnic University, Pomona, astrophysicist Breanna Binder in a NASA press release. “Regions like W51 are really important for advancing our understanding of star formation in the Milky Way, which we can extrapolate to how a star formation proceeds in other, nearby galaxies.”
More:
https://www.forbes.com/sites/kionasmith/2020/08/31/nasas-retired-spitzer-space-telescope-shows-us-where-stars-are-born/#1f921aeb54d6
