Global Astronomy Month - GAM 2010

If you happen to live in Ireland, here are some GAM 2010 events:

April 2nd - First Friday's at the Castle Blackrock Castle Observatory Cork - 4 X Family friendly workshops Cosmic Calendar’s. Free Event

April 2nd - 2012 Is it really the end ? a talk by Tony O' Hanlon at Blackrock Castle Observatory Free Event

April 2nd One People One Sky -Public Star Party Cork Astronomy Club at Blackrock Castle Observatory Cork. Weather Permitting Free Event

April 9th , 10th 11th , COSMOS 2010 - Midlands Astronomy Club Contact Seanie Morris
seaniehead@eircom.net A three day Astronomy Convention small entry fee
http://www.tullamoreastronomy.com/cosmos2010.html

April 19th Our Moon , Moon Stories, Moon News a talk by Deirdre Kelleghan
at Balbriggan Library Dublin 19:30 Telescope Observing Weather Permitting
Contact the library directly Tel: (01) 8704401 / 8704402 Free Event

April 22nd Our Moon , Moon Stories , Moon News a talk by Deirdre Kelleghan
at Swords Library Dublin 19:30 Telescope Observing weather permitting
Contact the library directly Tel: (01) 8404179 Free Event

April 23rd Irish Astronomical Society and Friends Public Star Party One People One Sky
20 :00 - 22:00 Martello Tower Car Park Sandymount Dublin Weather Permitting Free Event

April 24th -Irish Astronomical Society and Friends Public Star Party One People One Sky - 19:30 - 22:00 The Promenade Bray Co Wicklow . Weather Permitting Free Event

April 24th Public Star Party at Blackrock Castle Observatory by Cork Astronomy Club
20:00 - 22:00 Free Event

April 24th - Midlands Astronomy Club Kildare - Telescope Moon viewing
20:00 - 22:00 Athy Community College Free Event

April 24th - Ostan Arann Kilronan Inis Mor - Public Star Party 20:00 - 22:00 - Dara Molloy and the islanders. Free Event Contact Dara Molloy daramolloy@iol.ie

The Constellation of Leo

For the last of our late winter early spring constellations, let’s take a look at Leo, the Lion.

Leo is one of the constellations that actually looks reasonably like what it’s supposed to represent.

The brightest star of this constellation, alpha Leo, is called Regulus (meaning: the little king), it’s a blue-white star and when viewed with binoculars or small telescopes a fainter companion star of can be seen.
At the tip of the lion's tail the blue-white star beta Leo, or Denebola, viewed through a telescope beta Leo seems to have an orange companion, but actually the two stars are far away from each other – it is an “optical” double as opposed to a real double star system.

Another excellent double is the binary gamma Leo, or Algieba (the lion's mane), this pair, consists of a orange-red giant and a yellow giant, a small telescope is sufficient to split gamma Leo into the single stars.

Leo contains many bright galaxies, of which Messier 65, Messier 66, Messier 95, Messier 96, Messier 105, and NGC3628 are the most famous.

Have an enjoyable lion hunting safari!!

Image credit John Walker

The constellation of Cancer

For the second of our late winter early spring constellations let’s take a look at Cancer.

Cancer is best noted among stargazers as the home of Praesepe (Messier 44), an open cluster also called the Beehive Cluster or the Gate of Men. The smaller, denser open cluster Messier 67 can also be found here.

The constellation of Cancer is a difficult one to recognize even when you are looking right at it, so imagine how hard it is to find if you do not know anything about it. While this star grouping represented a giant crab to the ancient civilizations that named it, it looks nothing like a crustacean, resembling an upside-down "Y" if anything.

To locate Cancer, you must find two more easily identifiable constellations, Ursa Major and Leo, and then use them as a roadmap to the crab. You will find some instructions that may help here: www.ehow.com/how_5690312_constellation-cancer.html
Image credits: Cancer Till Credner. M44 NOAO/AURA/NSF

Messier Marathon

If you are looking for something interesting today this coming weekend why not try a Messier Marathon. A Messier marathon is an attempt, usually organized by amateur astronomers, to find as many Messier objects as possible during one night. The Messier catalogue was compiled by French astronomer Charles Messier during the late 18th century and consists of 110 relatively bright deep sky objects (galaxies, nebulae, and star clusters). For more information take a look here www.richardbell.net/marathon.html or here http://deepskymap.org/ or even here http://en.wikipedia.org/wiki/Messier_marathon.

Happy hunting!

Image credit: SEDS, the Students for the Exploration and Development of Space,

The constellation of Gemini

For the first of our late winter early spring constellations let’s take a look at Gemini. The constellation is dominated by Castor and Pollux, two bright stars that appear relatively close together, encouraging the mythological link between the constellation and twin-ship. The twin to the right is Castor, whose brightest star is α Geminorum (more commonly called Castor) and the twin to the left is Pollux, whose brightest star is β Geminorum (more commonly called Pollux); the other stars can be visualized as two parallel lines descending from the two main stars, making it look like two figures. At present a further “bright star” can be found to the left of Castor & Pollux, the star is in fact the planet Mars.

Viewed with good amateur telescopes Castor can be split into three components: Castor A and Castor B revolve around each other with a period of 420 years (less good telescopes may only split Castor into two blue-white stars of 2nd and 3rd magnitude). The third component, Castor C (also known as YY Gem) circulates this pair with a period of several thousand years.

There are two double stars in Gemini that are best viewed in small telescopes, epsilon Gem and 38 Gem. The first consists of a 3rd magnitude yellow super giant with a 9th magnitude companion. The second splits into a pair of white and yellow 5th and 8th magnitude stars.

With the help of small telescopes the planetary nebula NGC 2392 reveals an 8th magnitude blue-green disk about the size of Jupiter. When viewed with larger telescopes it shows a funny shape, which is why it is named Eskimo or Clown Face Nebula.

The open cluster M35 (also known as NGC 2168) is an outstanding cluster with about 200 stars. In binoculars or small telescopes it is visible as a hazy patch.

In the next posting we’ll take a look at Cancer.

Photo credits: Constellation chart IAU, M35 NASA.

The late winter early spring sky

Now that the moon is out of the way in the evening sky, take the opportunity to find some of the late winter, early spring constellations. If you have been looking at the sky regularly and at the same time each night (21h00 is a good time), you will have noticed that Orion has slowly “drifted” to the right (west) and its position has been replaced by other stars. The constellations that will dominate this part of the sky for the next month or so are Gemini (The Twins), Cancer (The Crab) and Leo (The Lion), all three being constellations of the Zodiac.

All three are interesting, but not all are easy to find; Gemini is very easy to find, just look for the two bright stars called Castor and Pollux. They represent the heads of the twins, while fainter stars sketch out two bodies; although Cancer the Crab is one of the more famous constellations, it is mostly made of dim stars; Leo's head and mane are formed by an asterism known as the Sickle which looks like a backward question mark, one of the brightest spring stars, Regulus being at the base of the question mark.

Try to find these constellations in the sky and over the next few postings will take a look at some of the interesting objects that can be seen with a pair of binoculars or a small telescope – double stars, star clusters, galaxies ……….