Dec 05

What’s Up in the Sky

What’s Up in the Sky – December, 2015

A Variety of Offerings in This Month’s Sky

December is not known for clear skies and warm evenings, so it’s a good month to concentrate on some basic observing of easily found objects. Like the Sun.

The winter solstice, which occurs on the date when the Sun rises and sets at its most southern point on the horizon, occurs this year on Monday, December 21 and marks the beginning of winter. You may remember last September when the Sun was shining right in your face as you drove down an east-west road early or late in the day. It is interesting to see how much the location of sunset changes so try to spot one using a westbound road or other landmark as a guide. You may be amazed at the difference.

The Geminid meteor shower is active from December 4 – 17, reaching a maximum on December 14. This is an interesting shower to observe as some of the meteors come in at a very low angle and therefore appear as long, bright streaks.

Lately I have been writing about spectacular observations of the planet Venus encountering the Moon or other planets and this month is no exception, except it’s another before sunrise event, this time on a Monday, no less.

But this one should be worth the effort because Venus will be a beautiful sight right below the crescent Moon. Since sunrise isn’t until about 8 a.m., it should be a spectacular sight as late as 7:30. For veteran observers, try tracking Venus until just past 12:30 p.m. when the planet will disappear behind the sunlit limb of the Moon. A challenging observation.

One of my favorite things to observe this time of year is the constellation Cygnus, the Swan. Also known as the Northern Cross, it’s bright star, Deneb, is part of the Summer Triangle that has been nearly overhead since late summer. This time of year, Cygnus sets a few hours after sunset and, if viewed as a swan, is diving into the western horizon. But if viewed as a cross, it stands straight up on the horizon and can be seen as one symbol of the Holiday Season. Regardless of your interpretation, it is a beautiful sight.

If you look toward the west, you see the constellations of summer and toward the east, the coming constellations of winter, but directly above you can find a constellation that points to another of my favorite objects.

Face south and then look straight up. A little beyond overhead you should see the “W” – shaped constellation, Cassiopeia. Using the right hand “point” of the W, follow it down to just about overhead and look for a fuzzy blob (binoculars help a lot). This is M31, the Andromeda galaxy. This is the only object in the sky visible to the naked eye that is not part of our own Milky Way galaxy and, at over two million light years, is the most distant object you can observe without the aid of a telescope.

All in all, it’s a good month for what’s up in the sky.

This month in history:
Dec. 3: Pioneer 10 spacecraft makes closest approach to Jupiter – 1973
Dec. 11: First auction of Soviet space hardware and artifacts – 1993
Dec. 14: Gene Cernan, Apollo 17 astronaut, is last human to walk on Moon – 1972
Dec. 14: Tycho Brahe born – 1546
Dec. 24: Apollo 8 astronauts give us inspirational moment from lunar orbit – 1968
Dec. 25: Isaac Newton born – 1642

Nov 08

What’s Up in the Sky

What’s Up in the Sky – November, 2015

The Morning Planet Show, Act 2

Normally, this time of year does not bode well for observing due to cloudy skies and generally bad weather. I don’t care. I always enjoy writing about it anyway.

Last month I recommended you observe the planets in the morning and this month the show continues. Unfortunately, the end of Daylight-Saving Time on November 1 means the Sun will rise one hour earlier so you will have to be out no later than 6:30 a.m. in order to catch the scene.

Starting on November 1, look toward the east one hour before sunrise and you will see the familiar sight of brilliant Venus with bright Jupiter above and to the right. With binoculars, look for much dimmer Mars slightly below and to the left of Venus, about one Moon diameter away. Watch as these two planets pass each other from day to day until the real show, which runs from Thursday, the 5th through Saturday, the 7th, when the main players are joined by a lovely crescent Moon. On Friday it will be right next to Jupiter and on Saturday very close to Venus, with Mars just above. Binoculars will add extra enjoyment.

If you’re really an astro-nut and are looking for a rare observing opportunity, you are in luck because this month you may have a chance to observe something I never saw in thirty years until last month – a full-Moon occultation. You may recall an occultation occurs when one object, such as the Moon or a planet, passes between Earth and a distant object, such as a planet or star. One of my first, and still most memorable, observations was of the Moon occulting Aldebaran in April of 1979. Readers with planetarium software should check out that date.

Anyway, full-Moon occultations occur when the full Moon passes in front of a star, which is fine except almost all stars are invisible when they are right next to a full Moon – like a candle next to a spotlight. I was fortunate enough to have witnessed such an event during September’s lunar eclipse. With the Moon embedded in Earth’s shadow, it no longer drowns out the nearby stars and I was able to observe it moving in front of a star – very exciting.

Your chance this month will not involve an eclipsed Moon, but rather a bright star. Each month the Moon follows a regular, rather narrow path across the sky which includes very few bright stars, but this month it occults Aldebaran, the brightest star it can ever pass across.

To witness this event, you will again have to be an early riser as the star disappears close to 5:40 a.m. Because of the Moon’s glare, you will need a telescope at high power, but because of the star’s brightness, you have a rare chance to make a difficult observation of something very cool up in the sky.

Oct 04

What’s Up in the Sky

What’s Up in the Sky – October, 2015

Good Morning, Planets

I hope you were not deterred by the cloudy skies last Sunday because it cleared up just in time to enjoy the total lunar eclipse. The astronomy club viewing at Kollen park was both enjoyable and informative. Visitors were able to view the eclipsed Moon through a telescope and then learn about the event from club members who were on hand to answer questions. This was a special eclipse, being the last of the current tetrad as well as occuring when the Moon was at its closest point to Earth in its orbit – a “supermoon”. All these conditions will not occur together again until 2033.

I often write about observing the planets and Moon because they are usually bright, easy to find and often move noticibly from night to night. Unfortunately, this month it will be morning to morning.

You may recall the close encounter between Venus and Jupiter last June. This month they put on a similar show as they again move gradually toward each other until, on October 25, they will only be separated by the width of two full Moons. Only problem . . . you will have to get out an hour before sunrise to see them. It’s not as bad as it sounds, however, since the Sun rises around 8 a.m. And it will be a very cool sight, especially on October 8 – 10 when the two bright planets, although not nearly as close together as later in the month, will be joined by a thin crescent Moon. Plus, the dim planet Mars will be in the same field of view. Look toward the eastern horizon anytime after 6 a.m.

In other news, we’ve had some pretty spectacular space missions this year, flying past Pluto for the first time, orbitting an asteroid and landing on a comet to name a few. But lost in the background radiation is a pioneering spacecraft, born in the last century, tempered by its long journey, and disciplined by a never ending quest for knowledge. It’s called Cassini.

Launched eighteen years ago next month, Cassini is a flagship class spacecraft, the largest and most complex ever built by NASA, and the first to orbit Saturn when it arrived in 2004. It also carried the Huygens probe, a lander that touched down on the surface of Saturn’s largest moon, Titan, in 2005. This in itself is an amazing accomplishment, being the first landing of any kind in the outer solar system.

But Cassini has made many exciting discoveries in the past decade. During its more than 200 orbits, it has studied features in the rings, a hurricane on Saturn, lakes of hydrocarbons on Titan, and geysers of ice on the moon Iapetus. Its latest discovery may be the most intriguing – below the icy crust of the moon Enceladus is a water ocean extending around the entire globe. The mission will continue until 2017, and I am sure there are many more exciting discoveries to be made up in the sky.

Sep 06

What’s Up in the Sky

What’s Up in the Sky – September, 2015

Eclipse of the Harvest Moon Highlights September

September has always been one of my favorite months for observing. Often the skies are clear, there are numerous objects of interest to observe, and it’s the month of the harvest moon. Personally, I have many fond memories of taking my astronomy students out for their first observation. Beginning-of-school enthusiasm along with interest in a brand new subject resulted in enthusiastic students who shared my excitement when looking through the telescope. It helped, of course, that there were many interesting items to observe. I will share some of my favorites with you and encourage you to look for them yourself.

Let’s start with naked-eye objects. The first task is to find an observing site that has a pretty good view of at least one horizon and is away from lights. Look straight up and you will see the Summer Triangle, consisting of Vega, Deneb, and Altair. Use a field guide or your favorite app to identify the constellation each star is in. Looking northwest and you will see Ursa Major, the “Big Dipper”, lower in the sky. Find the three stars that make up the handle of the Dipper and test your eyesight on the middle one by seeing if you can spot its nearby, dim companion. For a very cool sight, aim your telescope at that middle star. I will let you discover this for yourself, but I will say you will be seeing double.

Other good telescopic sights include the double star at the head of Cygnus, the Swan, M57, the Ring Nebula in the constellation Lyra, and M31, the Andromeda Galaxy visible in the eastern sky just to the left of the Great Square of Pegasus. Again, field guides and star charts are available at many bookstores and there are a number of apps to help you in your search. At least now you know what to look for.

The main attraction in September’s sky is, however, the Harvest Moon which is special this year because we will be able to watch as it passes through Earth’s shadow for a total lunar eclipse, the fourth of the current tetrad of four total eclipses of the Moon within two years. Plus, this will be the biggest eclipse you will ever see! That’s because the Moon will be the closest to Earth it has been all year and will appear thirteen percent larger than than it did last April during the last eclipse.

The action begins around 9 p.m. when the Moon first starts to move into the umbra, the dark inner portion of the Earth’s shadow, where the Sun would be totally blocked for a viewer on the Moon. This is the partial eclipse stage of the event and is followed about an hour later by the total eclipse stage, when the Moon is completely engulfed in Earth’s shadow.

During totality, the Moon may appear to be deep red or orange in color. This is due to sunlight being scattered by Earth’s atmosphere, just like during a sunset. An observer on the Moon would see a black Earth ringed by a thin, red glow which lights up the lunar landscape. Don’t miss this beautiful sight up in the sky.

This month in history:
Sept. 1: Pioneer 11 is first spacecraft to fly past Saturn – 1979
Sept. 3: Last two Apollo Moon landings canceled by NASA – 1970
Sept. 8: Voyager 1 launched – 1977
Sept. 20: Wernher von Braun arrives in US – 1945
Sept. 23: Carolyn Herschel discovers NGC 253 – 1783
Sept. 30: End of daily communication with Pioneer 11 – 1995

Jul 16

What’s Up in the Sky

What’s Up in the Sky – July, 2015

More to Come!

I hope you were able to witness the close pairing of the planets Venus and Jupiter on June 30. It was certainly a rare event.

Seeing two planets – ANY two planets – at the same time in a telescope with a magnification of 60X is quite rare, to say the least. So I hope you were able to take this opportunity either with your own scope or by joining us at the State Park.

Later this month (July 14 to be exact) another close encounter will take place, this time not just in appearance but in reality. The New Horizons spacecraft, launched January 19, 2006, will fly past Pluto, the best known object in the Kuiper Belt.

Another dwarf planet, 1 Ceres, is currently being studied by the orbiting Dawn spacecraft. Unlike Dawn, New Horizons will not be able to orbit Pluto, but instead will zip by at over 8 miles per second on a one-way trip out of the solar system, like Voyager and Pioneer at Saturn. For a 48 hour period, it will be close enough for serious study.

Holland resident and SAAA member, Dr. Harold Reitsema has been a project scientist on the New Horizons mission since its beginnings. He informed me that images from the spacecraft already show surface markings on Pluto. During closest approach, data will be collected to get a better understanding of atmospheric activity and its effects on ice deposits.

Due to its great distance, resulting in a SLOW data feed, the results of the flyby will not be downloaded and processed until the fall. You can follow the mission on the web after a quick search on NASA’s web site.

Next month I will give you an update on the New Horizons mission as well as the LightSail mission about which I wrote last month.

Lots of under-reported history is happening up in the sky.

This month in history:

July 1: 100 inch mirror arrives at Mt. Wilson – 1917
July 4: Deep impact collides with comet – 2005
July 10: First transatlantic TV signals made possible by launch of Telstar – 1962
July 18: John Glenn born – 1921
July 20: First Humans walk on Moon (Apollo 11) – 1969
July 24: First rocket launched from Cape Canaveral – 1950

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