As we look for great objects in the night sky to practice our observing skills on, what are some of the best examples for late Winter and early Spring? Last month we focused a lot on the constellation of “Orion, the Hunter” and the good news is that it’s still high and prominent in the sky! So we’ll be using it both as a source of deep sky objects and as a guidepost to other bright stars and constellations.
By far the greatest deep sky object within Orion is the Orion Nebula, a massive cloud of dust and gas that has been giving birth to new stars for the last 300,000 years. The ultraviolet radiation from those young stars is what causes the gas to glow like a fluorescent light bulb. Even at a distance of over 1500 light years, the Orion Nebula can be seen in binoculars as a faint smudge of light surrounding the middle star of Orion’s Sword hanging from the belt.
The constellation of Orion makes for one of best “pointers” in the sky because of its unmistakable belt stars – the three bright stars in a line near the center. In this month’s installment of “Gateway to the Stars” we’ll use the belt stars of Orion to find another famous nebula – the Crab Nebula in Taurus the Bull. While not nearly as big and bright as the Orion Nebula, the Crab Nebula is special because it is the remnant of an exploded star. When a particularly massive star dies, it explodes as a supernova. The core survives, in this case as a Pulsar, surrounded by the tattered wreckage of gases and dust that we see as the Crab Nebula.
But constellations and deep sky objects aren’t the only thing we’ll be talking about! A beautiful “conjunction” of the planets Jupiter and Mercury will take place on March 15, and we’ll give a preview of what it’s going to look like on the dome. Since Mercury doesn’t appear to wander far from the sun in the sky, it will be very low on the western horizon soon after sunset.
And speaking of Mercury, we’ll also cover a historic event happening March 18 – NASA’s MESSENGER space probe will become the first spacecraft ever to fall into orbit around the first planet! After more than six years and three previous flybys of Mercury, MESSENGER finally has the right speed and trajectory so it can burn its rocket motor and become the first satellite of Mercury.
Come and see what else you can explore in the next “Gateway to the Stars,” Saturday March 5, 2011 at 6:45 p.m. in the Hansen Dome Theatre. Tickets are just $1 at the window and $2 online. Members can attend the presentation for free as part of the membership program.