Skywatch for the week of October 9, 2023
Mon Oct 9, 2023 MOON AND VENUS TOGETHER
Tomorrow morning a couple of hours before dawn, you’ll be able to see the moon and the planet Venus together in the eastern sky. The moon will be a thin crescent, and Venus will appear as a brilliant star-like object right next to it. Just above Venus you may also see a real star, called Regulus, which marks the heart of the constellation Leo the Lion. You’ll be able to see Venus every morning before dawn for several weeks, but the moon will be moving on eastward, approaching the sun’s position by the end of the week. On Saturday morning, October 14th, the moon will be directly between the earth and the sun, and here in Florida we’ll be treated to a partial solar eclipse. Indian River State College’s Hallstrom Planetarium will be providing safe, guided observations of this eclipse, beginning at 11:30 that Saturday morning.
Tue Oct 10, 2023 THE END OF THE WORLD
The astronomer Harlow Shapley once suggested two possible ways that the world could end. In one scenario, the earth loses its forward momentum, and the sun’s gravity pulls our planet inward to a fiery destruction. Another theory supposed the opposite might happen, that the earth might drift outward and suffer a frozen death like Mars. Of course, both “fire and ice,” may be our ultimate fate. Five billion years from now, when the sun runs out of fuel, gravity will take over and collapse it. This will heat it up, and the sun will expand to become a red giant star, engulfing the inner solar system, including earth. Then, when the last bit of helium fuel is exhausted, the sun will collapse again, heating up, turning into a high energy white dwarf! So, let’s make it a point, five billion years from now, to get off the planet!
Wed Oct 11, 2023 OLBERS AND HIS PARADOX
Heinrich Wilhelm Olbers, who discovered the asteroids Pallas and Vesta a couple of hundred years ago, was born on October 11, 1758. He is best known for what’s called, Olber’s Paradox. Olbers asked a simple question: "why is the sky dark at night?" Now that seems a bit silly - after all, the sky is dark at night because the earth rotates into its own shadow, what we call night. ”I know that,” he said. But if the universe is infinite in size, then that means there's an infinite number of stars out there. So no matter where you look, you'll eventually find a star - the sky should be ablaze with light! But it's not. This suggests that the Universe is perhaps not infinite, and that there was a definitive point in time in which everything began, and also that our Universe is expanding!
Thu Oct 12, 2023 HOW TO SEE A BLACK HOLE
In the autumn evening sky, there are three bright stars high overhead which are called the Summer Triangle. In the middle of this triangle there is a great mystery - something which is invisible to the eye - that enigmatic phenomenon known as a black hole. It is called Cygnus X-1, and we can't see it directly because its gravity field is so intense that light can't escape it. But we know that it is there, because we've discovered an incredible amount of x-rays pouring out of this part of the sky. Cygnus X-1 is part of a binary star system. Gas from its companion, a massive blue giant, is being pulled from it to feed the accretion disc surrounding the hole; it’s here that the x-rays are being made, just outside the black hole's event horizon - its point of no return; it’s about 2500 parsecs, or a little less than 48 quadrillion miles from Earth.
Fri Oct 13, 2023 SOLAR ECLIPSE VIEWING
There will be a solar eclipse tomorrow, beginning here at 11:55 am. Indian River State College’s Hallstrom Planetarium will be open and we will provide safe views of the sun during the eclipse. It is not safe to view the eclipse without a protective filter for the eyes, so we will have them on hand throughout the day, available at the Planetarium. There will be two astronomy clubs – the Treasure Coast Astronomical Society and the College student club, who will be ready with telescopes to safely watch the eclipse. If it’s cloudy this Saturday, we will hold the event indoors, by projecting an image of the solar eclipse onto the dome – I’ll pipe in a real time image from an observatory where the skies are clear. The eclipse ends at 3:07 pm. Come on out anytime to watch something that’s truly out of this world!