The Family-Friendly Eclipse of the Moon

This will be the lunar eclipse you and your kids will remember....if the sky is clear on the evening of Sunday, September 27, 2015.

In the past 18 months, we've had three other lunar eclipses -- in cold weather, or at crazy hours of the night or morning. Finally, we have a lunar eclipse at a decent time of night and at a comfortable time of the year. If you miss this lunar eclipse, you'll need to wait a few years for anything as convenient.

A lunar eclipse happens when the Earth is perfectly aligned with the Sun and the Moon. We get "almost aligned" every time there's a Full Moon. But normally, the Moon passes a little above or a little below our shadow in space -- no eclipse. During a total lunar eclipse, the Moon passes near the center of the Earth's shadow. And because the Moon is illuminated by sunlight, our shadow slowly turns the bright Full Moon into a dim, reddish-orange ball for a while.

Partial Phase from April 2015

It's totally safe to view a lunar eclipse with a telescope or binoculars or your plain eyes. There's no danger to your eyes as there is in a solar eclipse. You can easily watch the whole eclipse just using your eyes. For kids it can be easier to watch that way. A telescope is nice, but if you have binoculars you'll have the best combination of ease and magnification.

It takes a while for the Moon to slowly move through our shadow. So if you plan to watch you'll need to decide how to use the time. If you or your kids are impatient, you might just plan on watching a little every so often. If you plan to be outside for the whole event, you can look at the beautiful summer and fall constellations, like Cygnus the swan, Hercules, Pegasus and Cassiopeia. (You can print out a free map of the sky from the Skymaps.com website.)

You don't need a really dark sky. This eclipse would be easy to view from the middle of Salem. But if you can get to a darker spot without too many trees and buildings, you'll be able to enjoy the Milky Way, high overhead.  You will want to find a place where you can see to the east and southeast. The nearly Full Moon will rise due east and as the eclipse progresses, the Moon will move higher in the southeast. If you don't have a good view to the east or southeast from home, try a park or sports field. A place like Shawnee Mac Lakes should provide a very good vista of the eclipse over the water.

Here's the timeline for the eclipse: The "partial" phase of the eclipse starts at 8:07 pm. You'll see the upper left part of the Moon look like someone took a small bite out of it. That dark area will get bigger and bigger. At about 9:10 pm, only a little sliver of bright Moon will be remaining and it'll be gone in just a few minutes.

Then the "total" phase starts. The Moon won't be invisible because light passing through our atmosphere will illuminate it dimly. Usually, the Moon looks reddish, but the color is unpredictable. The middle of totality is about 9:50 pm when the Moon is deep into our shadow. (That's the best time to see the Milky Way.) At 10:23 pm, the lower left part of the Moon will start to pass out of our shadow. You should see a bright sliver appear. That's the end of the total phase of the eclipse and the start of the final partial phase.

Slowly, more and more of the Moon will be illuminated as it leaves Earth's shadow. By 11:30 pm the second partial phase is done, and the whole Full Moon will be back to (almost) its normal brightness.

By the way, this eclipse will be visible across the whole USA. The only thing that changes is the timing for folks outside Central Daylight Time. They'd need to adjust the CDT times listed here. So if you know people who might be interested, please share this information with them and tell them to adjust the times to fit their timezone.

If it's a little cloudy, you might still be able to view the partial phases, but you might not see the dim, totally eclipsed Moon through the clouds. So let's hope for pleasant temperatures and clear skies so we can enjoy this eclipse.

Meteor Shower Coming to Salem Skies August, 2015

We're nearing mid-August and there are three reliable activities in mid-August: Back-to-school sales, burning hot weather, and one of the best meteor showers of the year. You already know about the sales, and we can't avoid the weather, so let me fill you in on the upcoming Perseid (PURSE-ee-id) meteor shower. Meteors are one of the most entertaining and exciting objects in the sky (but not for long!). The action is best on the nights of August 12 and 13, so read on and be ready for the show if we have clear skies.

You've probably seen meteors flash across the sky in night. Maybe you've made a wish on one. Any night you might see three or four if you find a clear, dark sky and keep your eyes looking up. Those are random space bits -- bits of space rock from who-knows-where or tiny pieces of orbiting rockets. But several times each year, Earth's path crosses an area where comets loop around the Sun in their orbit. As comets orbit the Sun, they lose bits of dirt, ice, and stone and this debris drifts around along the orbit. If you've driven behind an open-bed truck full of sand, you can get a sense of the trailing stuff. As we pass through the orbital path of a comet, that comet junk hits our atmosphere and it burns up. That gives us a streaking light show for a moment. The best showers give the most meteors per hour. Our August shower can deliver more than 100 meteors per hour on the peak day, at the peak time and with clear, dark skies.

The shower is named "The Perseids" because the path of the meteors in the sky traces back to a point (the "radiant") near the constellation Perseus. That's not an easily recognizable constellation, but the radiant is also close to the easily recognized Cassiopeia -- the giant "W" in the sky. You can see the most meteors if you watch the area near the radiant. But if you want to see the BEST meteors, look above or to the side of the radiant. Those areas of the sky won't have the most meteors, but the long streaks are much more interesting than the short, stubby meteors near the radiant.

Watching meteors is the astronomy equivalent of fishing: It takes patience and you might need to make trade-offs that fit your circumstances. For example, the best time to see a lot of meteors is in the final stretch of darkness before the dawn twilight. 3-4 am might not seem like a time to have fun staring at the sky to see some meteors. But you can see the Perseids and other meteor showers in the late evening and later the vicinity of midnight -- you just won't see as many meteors as the die-hard pre-dawn folks.  The 2015 Perseids promise to be a good show because the Moon won't throw a lot glare around the sky. When the Moon is bright (as in 2014), we don't see many of the dim meteors. The Moon will be very dim this year so take advantage of the good arrangement.

Meteor watching doesn't require much equipment. For a meteor shower in August, you'll need some bug repellent. Most serious meteor watchers prefer a reclining lawn chair so to prevent neck stiffness. Telescopes and binoculars aren't much help because meteors move too fast. Just find a nice part of the sky to watch, stretch out, and enjoy. Avoid lights as much as possible. Kids can have fun with some late-evening meteor watching. They just need to watch the sky and shout when they see a streak of light.

The constellation Cassiopeia will be low in the northeast about 8:30 pm. Perseus will follow behind Cassiopeia as they both climb higher in the northeast. The radiant is between them. You can focus your attention there for the most meteors or look aside for the more exciting meteors.

If you miss the peak nights of August 12 and 13, you can still catch a few rogue Perseids for another 8 or 9 nights. After that, our next good 2015 meteor shower is in December: Good bye, bug repellent; Hello, heavy coat and gloves.

For more ideas on meteor watching and links to other meteor websites, check out the Salem Skies blog at http://salemskies.blogspot.com/2013/11/meteors.html .

Here are some other links for the 2015 Perseids:
http://patch.com/california/southpasadena/2015-perseid-meteor-shower-peak-when-where-how-view-across-us
https://in-the-sky.org/news.php?id=20150813_11_100
http://www.amsmeteors.org/2015/08/perseids-2015-the-amateur-guide/
http://www.skyandtelescope.com/astronomy-news/observing-news/plan-for-the-perseids/

Venus -- The Evening Planet

Venus -- The Evening Planet.

Police stations around the world need to be on the alert: There will be a jump in UFO reports from now through the end of July, 2015. But that "bright light" in the west just after sunset isn't a UFO. It's a planet -- our closest planetary neighbor, Venus. It will be routinely mistaken for a UFO or helicopter or something equally sinister. Once you learn the details about Venus's march across our sky, you can enjoy viewing Venus and some of the more interesting stops during its tour.

There are several reasons folks get agitated and suspicious about Venus in the night sky. First, it's bright -- really, really bright. Only our Moon is brighter in the night sky. Other planets like Mars, Mercury, Jupiter and Saturn appear as "bright stars" in the night sky. But, Venus is usually 10 times brighter than the brightest star in the night sky -- often more than 20 times brighter. So it looks far too bright to be a star. Anyone can see that it's obviously not part of a traditional constellation. It looks "wrong" in the sky.

Venus and dimmer Mercury set as Mars (upper left) waits.

The second suspicious behavior of Venus is hanging around the horizon. It looks like it's up to no good. Venus (like Mercury) goes around the Sun in an orbit inside of Earth's. That means we never see Venus at midnight because it's always in the same part of the sky as the Sun. So when Venus swings between us and the Sun or swings on the far side of the Sun, we don't see it in the morning or evening sky. The bright glare of the Sun hides it. During the rest of its orbit, we see Venus in the pre-dawn or post-sunset sky, but never too far from the Sun.

You can actually see Venus in the daylight sky on a clear day if you know where to look. But against a bright blue sky it doesn't stand out. It doesn't grab your attention. Then, when the evening sky starts to darken, Venus seems to jump literally "out of the blue" as a blazing object in the west or east. (We tend to notice Venus in the west because we're more active in the evening than in the early morning.) Venus stands out the most when the sky is dark and by that time, the planet is often close to the horizon so it looks like it's hovering.

The final odd behavior of Venus is the appearance of flashing colors, especially close to the horizon. This is a combination of the brightness of Venus and the density of our atmosphere. The same air that causes the blue sky, the red and orange sunsets, and twinkling stars is behind Venus's curious lighting. As light passes through a lot of turbulent air, it gets separated (as with a prism) and twisted. High in the sky, Venus will be a bright, steady white because there isn't much air to twist the light. But close to the horizon the light travels through more of our air and you might see momentary flashes of red or orange or green or blue. Venus is still white, but that white light has been distorted before it gets to your eye.

When you combine these factors -- distinctly bright, hovering on the horizon, flashing colored lights -- it's not surprising that Venus motivates people to call in a report. It happens whenever Venus starts to make its appearance in the evening skies.

You can still enjoy Venus even though it isn't a UFO. You can use a telescope or binoculars if you want. But you don't really need anything more than your eyes to appreciate it. A nice telescope can show the phases of Venus -- much like the phases of our Moon. Early in the year, Venus will look like a bright white ball in a telescope. Its white clouds cover the planet. We never see any of the planet's surface like we can for the Moon and Mars. Eventually, that white ball will change into a half-Venus and then a crescent-Venus by the end of July. But we're always seeing those plain, featureless clouds.

In January, 2015, Venus is passing behind the Sun (as we see it) and it will continue to lap us -- much like a race car uses the inner path to pass a car on an outer path. It will start the year 150 million miles away from us, and end July "only" about 30 million miles away. By August, Venus will appear so close to the Sun that it will set just 30 minutes after sunset -- not enough time for the sky to darken.

As it passes through the sky Venus will appear to be near different stars, planets, and star clusters as well as the Moon. When the Moon or a planet gets close to something else in the sky, astronomers call that a "conjunction". You can enjoy most of these conjunctions with just your own eyes or binoculars. Below is a list of some of the best conjunctions for Venus's 2015 visit to the night sky. The ones marked "(T)" will need a telescope. Venus traipses slowly through the constellations, so you can enjoy most of the conjunctions a day before and a day after the listed date. The Moon moves faster through the constellations so you'll need to view any of the lunar conjunctions on the date listed. Some of the conjunctions include three objects (triplet) or four objects (quartet).

So enjoy the shining light of Venus as it wanders around our evenings for most of 2015.

STOPS ON THE VENUS 2015 TOUR

January 21: Wide triplet with Moon, Mercury
February 1: Close to Neptune (T)
February 20: Triplet with Moon, Mars
February 21: Close to  Mars
March 4: Close to Uranus (T)
March 22: Close to Moon
April 10: Close to Pleiades star cluster
April 21: Wide triplet with Moon, star Aldebaran
April 30: Close to star Alnath
May 21: Wide quartet with Moon, stars Castor, Pollux
May 29: 3° From star Pollux
June 2: Wide triplet with stars Castor, Pollux
June 12: Wide triplet with Jupiter, star Regulus
June 13: Close to Beehive star cluster
June 19: Wide triplet with Moon, Jupiter
June 20: Wide triplet with Moon, Jupiter
June 30: Close to Jupiter
July 18: Wide quartet with Moon, star Regulus,  Jupiter
July 14: Close to star Regulus