As 2019 came to a close, the news media sensationalized a story about Orion’s bright star Betelgeuse. The headlines were certainly designed to get one’s attention. Betelgeuse was about to go supernova. However, the star’s behavior was really old news that was recently enhanced by new observational data. You see, Betelgeuse is a red super giant star (20 times more massive than our Sun and approximately 1000 times larger) that is indeed nearing the end of its life cycle. And with a star this massive, the result will someday be a supernova event.
Betelgeuse is a known variable star, which pulsates back and forth about one full magnitude (brightness scale) in a 425-day period. What happened more recently is that the star dimmed a little more than usual, by about .2 of a magnitude. An imaging technique using radio waves revealed Betelgeuse appeared to be lopsided, but this discovery turned out to be a huge dust cloud blocking some of the star’s light from reaching us. In fact, Betelgeuse has shed off great shells of its outer surface several times in the past, typical activity for these stars as they “burn” through their supply of nuclear fuel. Speculation arose that Betelgeuse’s grand finale was soon at hand.
However, every article I read succinctly stated the event could happen soon, or 100,000 years from now. While it is inevitable that Betelgeuse will go supernova in the future, we needn’t worry. Fortunately, at its distance of about 700 light years from the Earth, we will not suffer from any hard radiation effects. The supernova will be at least as bright as a Full Moon and will be visible in broad daylight. About a day before we see the visible light from the supernova event our Earth will be bombarded by a harmless hail of neutrinos and gamma rays. That onslaught will be our advance warning system that Betelgeuse the star has met its demise.
Continue reading Supernova deferred (for now), Easter, and a meteor shower
As quickly as it started, 2019 will soon be in the history books. I for one am happy to see it go. A cloudy and rainy spring, hot and humid heat waves during the summer, then the EEE mosquito threat have conspired to prevent casual stargazers and amateur astronomers alike from enjoying the night sky and all the wonders it holds. It would be great if we could end the year on a high note, but the sky gods are not smiling down on us for December.
Though the Geminids are the best meteor shower of the year, peaking on the night of December 13-14, the Full Moon on the 12th will overwhelm all but the brightest meteors. To complicate matters further on the peak night, that bright moon will be sitting right in the middle of the Gemini constellation. While you won’t require my usual star map to find Gemini, the proximity of the Moon to the region of the sky from where the meteors appear to radiate (near Gemini’s brightest stars, Castor and Pollux), will certainly reduce your meteor count. .
However, one does not have to look directly at Gemini to catch a few of the brightest shooting stars. In fact, the Geminids are fairly bright and also have a reputation for producing exploding meteors called fireballs, My point: if the weather cooperates on peak night do not give up on the Geminids. You might just glimpse a few bright Geminids as they enter our atmosphere at 21.75 miles per second.
Continue reading Geminid Meteor Shower Mooned Out and Other Celestial Offerings
First up for November is my reminder to be sure to set your clocks back one hour on Sunday, the 3rd. That’s when most of the United States switch back to Eastern Standard Time from Daylight Saving Time. The mnemonic is “spring ahead and fall back/behind”. Thank goodness for most of us it occurs on a weekend!
While the premiere astronomical event during November will be the transit of Mercury between the Earth and the Sun (which I will preview in a separate column), there are two meteor showers as well.
From November 4th thru the 6th watch the sky for no more than a half dozen or so Taurid meteors. These often very bright yellow fireballs (meteors that explode and fragment into multiple pieces) are fairly slow and enter our atmosphere at approximately 17 miles per second. Observe after midnight to increase your chances of seeing one. Look in the general direction of the constellation Taurus. To locate Taurus find the V-shaped pattern that defines the bull’s face, or locate the Pleiades — the Seven Sisters star cluster. A waxing gibbous Moon will overshadow all but the brightest of the meteors this year.
Continue reading November Meteor Showers
If recent events during the last few months are any indicator, Chicken Little may have been right. The sky is falling. The sky is falling. Back on July 24 at approximately 2:44 a.m. EDT, a soccer ball-sized meteor entered the Earth’s atmosphere above Lake Ontario and became a bright fireball as it disintegrated. Click here to learn more about this event. Fragments of this “space invader” most likely reached the ground. That same day, at around 11:04 p.m. a similar object was sighted along the east coast from Virginia to Maine. But wait! There’s more. The very next day a previously unknown asteroid estimated to be 187-427 feet across zipped past the Earth at 11:22 a.m., travelling around 45,000 miles per hour. Talk about close encounters! That one would have wreaked havoc had it collided with the Earth.
There’s a lot of space debris that the Earth passes through on its journey around the Sun. The vast majority are harmless remnants of comets or small pieces of asteroids. Everyday the Earth is bombarded with this material, and with greater frequency security cameras are recording the demise of the brightest of these visitors to our planet. After careful examination of eyewitness accounts, astronomers can determine the orbit of these bodies and determine if they are associated with a particular meteor shower. Two meteor showers were in progress at the time of the fireball reports. Many folks were lucky to view such a “fiery” display.
Continue reading October meteor showers
While the Geminid meteor shower of mid-December reigns supreme as the northern hemisphere’s most productive display of shooting stars, August’s Perseids, coming in a close second, are the most widely observed meteor shower of the year. Why? Warm temperatures find families spending more time outdoors during the summer season enjoying cookouts, camping, or any other assortment of late evening activities. Normally 60+ green, red or orange Perseids can be observed per hour during peak activity. Unfortunately, for 2019 a waxing gibbous Moon (Full on the 15th) will severely hamper observing this meteor shower which peaks on the night of August 12-13.
However, while moonlight will wash out all but the brightest meteors before midnight on the night of the 12th, once the Moon sets around 3:48 a.m. that will leave just over an hour of dark sky observing time before dawn’s early light begins to brighten the sky. Somewhat helpful is the fact that Perseus, the constellation from where the meteors appear to radiate (known as the radiant point), is completely opposite the sky from the Moon. This circumstance could help extend your window of opportunity to an hour or two before the Moon sets! Hey, I’m trying my best to be optimistic here!!
Continue reading Poor Prospects for the Perseids