This month’s performance of Gateway to the Stars on Saturday, May 3 will feature the grandest objects in the universe – the “galaxies.”
For centuries, our Milky Way Galaxy was thought to house all of the components of the universe. But as telescopes got larger and astrophotography improved in the late 19th century, many clouds of gas (especially those described as “spiral nebulae”) were suspected to be separate galaxies outside the Milky Way (“island universes” in their own right).
In the early 20th century it was confirmed – the universe had thousands of other galaxies in addition to the Milky Way, and the universe suddenly got a whole lot bigger. Now, with the help of the Hubble Space Telescope and huge ground-based observatories, we can confirm the existence of several hundred billion galaxies, each containing anywhere from a few billion to over a trillion stars. Mind boggling, indeed. But also an opportunity to understand how our universe has transformed and gave rise to spiral galaxies with solar systems like ours.
From the Earth, what we call the Milky Way (that faint band of light that sometimes stretches across the sky) is actually just a portion of two nearby spiral arms in our galaxy. We’re simply looking at our local galactic neighborhood. But the Spring skies are different – the Milky Way seems to be mostly absent in the sky! That’s because sometimes our planet is looking out of the plane of our galaxy, and so the band of the Milky Way seems to be laying around the horizon where it’s impossible to distinguish from the horizon glow.
But that also means we don’t have as many stars or as much dust and gas high in the sky to obscure our view of what lays outside of our galaxy. We get a fantastic opportunity, when the skies are clear and dark, to peer millions of light years into what’s called “intergalactic space.” And when you do, you will find the faint little blobs of light that represent other galaxies in distant space.
Of course, seeing galaxies requires a telescope and a star atlas so you know how to locate them. (Check out the star parties put on by the Salt Lake Astronomical Society.) That’s just a part of what we’ll demonstrate in the Gateway to the Stars show. We’ll give you tips on how to observe these distant relics of the universe.
So join us on Saturday May 3 at 6:45pm in the Hansen Dome Theatre. You’ll also have a chance to see what’s going on with the planets – Mars, Jupiter and Saturn are all visible right now! Tickets are only $2 and planetarium members are free.