It’s a stunningly beautiful day here on the mountain. I stood by the bee field, marveling at a maple ablaze in orangish red. The wind crept up, and shook out the branches, leaves falling like a thousand embers. Down the hill, the path wound among russet Sycamore leaves into the distance. I turned east, boots crunching fallen acorns. A slight oaky smell hung in the crisp air, and the playful breeze skipped along home with me.
Happy Friday! I hope your brew of coffee is strong. Mine is - it was an unexpectedly late night logging some star observations for this post. I got stuck in the glow of the Andromeda galaxy.
Space Time!
There’s two things that must be shared today: The sighting of the young crescent moon, and a galaxy pair that’s 110 million light years away.
They’re written for my blind friends, but I hope everyone enjoys the descriptions.
Let’s start “close” to home.
The Moon: Description
The slim crescent moon hung in the clear western sky, about 15 degrees above the horizon. The sunset had just happened, leaving an orange dome low, fading into white, then faint green, then light blue, then darker blue.
The moon hung in the darker blue, illuminated by the just-vanished sun. It gave the impression of a giant rotisserie chicken being roasted over the sunset, that orange glow cooking it nicely.
Earthshine
While the crescent shape was the most obvious, a giant cosmic smile, Earthshine was there, too. A faint ashen light illuminated the rest of the moon, making the part not lit by the sun a dim gray.
If we went to the moon, the Earth would be nearly full in the sky. That light is “earthlight”, sunlight reflected off our blue planet.
Another way to imagine it is to take a quarter, and put just the edge of it under a faucet. The running water would be the sunlight illuminating the edge of the coin.
The rest of the quarter is still there, and detectable, but not as obvious.
Scorpio Moon
I noticed a reddish star twinkling in the sunset just to the east of the moon. Grabbing some binoculars, the confirmation was made. It was Antares, a red giant star, “Rival of Mars”, alpha of the constellation Scorpius. Three other stars that made the “claw” of the creature glittered blue-white in not-quite-dark sky.
“Mmm…Scorpio moon! What a sight!”
Distant Galaxies: Preface
I put the telescope outside at dusk. Practically speaking, the mirrors operate best when they’re cooled to ambient temperature. Josh speaking: It feels like the spaceship is warming up on the launchpad. Get me my astronaut ice cream!
Phil Harrington had posted a new “Cosmic Challenge”, his monthly column over at Cloudy Nights, and I wanted to try it. The boring catalog name “NGC 7541” doesn’t convey the staggering distance it’s light has traveled. It’s a galaxy 110 million light years away. (For comparison, the Andromeda Galaxy is 2.5 million light years distant. Humans have only traveled less than two light seconds when they went to the moon.)
With star charts in tow, I went out to the waiting spaceship…errr, telescope.
Distant Galaxies: The Hunt
The fall constellations wheeled high overhead. Jupiter blazed brightly near the target, a “street light” in the neighborhood that is our our solar system, shining a path towards adventures in deep space.
I located a small circle of stars in the constellation Pisces, the fish. They call it the Circlet. Who names these things?
Looking through the eyepiece, I moved the telescope a bit to the west, following a chain of dim stars. “OK, if I make a triangle with that one, and the other one, the galaxy should be at the point.”
Sure enough, there was a faint wisp, a smudge, a ghost of an idea.
I increased the magnification.
Distant Galaxies: Description
A half-dozen stars glittered feebly in the view. These were “close”, still members of our own galaxy, probably a few thousand light years distant.
There, in the uniform gray-black, something glimmered.
“Wait a second, Josh! Why isn’t the view pitch black?” you might ask.
Light pollution here on earth muddies the view. If we were in space, well, yes, it would be completely black.
NGC (New General Catalogue) 7541 was definitely there, looking like a faint cloud stretched east to west, like a tuft of cotton pulled almost to breaking.
And next to it was a fainter companion, NGC 7537, about twice as dim, smaller, a “kid ghost.”
The gray glow of the galaxies could scarcely be noticed from the background of the sky, but there they were!
The Hubble Telescope has photographed the pair in great detail, with billions of stars, blue arms, an orange bar of stars cutting across the center, dark dust lanes, glowing nebulae, and higher-than-usual rates of star formation.
They just looked like nearly imperceptible smudges through my backyard telescope.
But, my mind’s eye filled in the blanks, and knowing it was a “live view” added to the thrill.
Distant Galaxies: Thoughts
The dim view seemed watery. Perhaps the constellation Pisces put the thought in my head, but these galaxies seemed like celestial whales, surfacing from the deep.
Gazing across 110 million light years, I was looking back in time. Those photons started their journey to this blog when dinosaurs were still around, and flowers were proliferating here on Earth.
The light would have been halfway here by the time whales first appeared.
Gems from Earth
While classical is the usual feature on Fridays, that maple tree from the beginning of this post decided the selection while I stood in the field. Eva Cassidy’s Autumn Leaves deserves a spin.
Enjoy this breathtakingly melancholy version…but I hope your weekend rocks! See you on Monday for a Dr. Electro and a Happy Halloween!