International Observe the Moon Night - September 18, 2010

Advanced notice of an interesting international event, the "International Observe the Moon Night" to be held on September 18, 2010.

InOMN is a community-based effort where everyone can share the excitement of lunar exploration with the public by hosting their own InOMN events. Public telescope observing events, lectures, school presentations and workshops, and even online events like TweetUps are already being planned.

For more infomation click here: www.astronomerswithoutborders.org/projects/intl-observe-moon-night.html

Global Star Party

On Saturday, April 24, the Global Star Party gives you an opportunity to bring your community’s attention into sharp focus on the sky, in concert with your brother and sister astronomers all over the world. All are invited, all will be excited. It is amazing that when we turn our gaze upward, all religious, national, geographical, cultural and political barriers fade into the darkness.

For more information, see here: www.astronomerswithoutborders.org

Planets galore!

This week is an excellent opportunity to see all the five “naked eye” planets in one night of observation.

You need to start about an hour after sunset by looking relatively low on the western horizon, you should be able to make out both Mercury and Venus, Mercury being the lower and fainter of the pair. You then need to look almost directly above your head to spot Mars – with it’s reddish hue you shouldn’t miss it. Saturn can be found by looking towards the east (to your left); if you have a telescope take a look, even a small instrument should show the famous rings. For the final of the five planets, Jupiter, you need to wait until the morning and take a look low on the eastern horizon about an hour before sunrise.

As the month progresses there will be some interesting encounters to watch out for – Venus and the Pleiades, the Moon and Saturn, Mars and the Beehive………. So keep reading the blog for more information.

30 Nights of StarPeace

The Sky literally brings together the Earth during GAM-be part of a global peace chain!

Inspired by the idea of sharing the beauty of the sky across national borders, "Thirty Nights of StarPeace" is a worldwide-scale event that will join together astronomy groups in neighbouring countries, one patch of Earth at the time, on successive nights during the month of April.

Using geographical longitude as a reference, we've divided the Earth into ten equal segments, each one spanning 36 degrees of longitude. Countries located in each of these 10 segments will have a period of three days to participate in the Thirty Nights of StarPeace project.

What you have to do is synchronize your group with an astronomy group across your national border, so that both groups observe the beauty of the sky at the same time. We will start at 180 degrees longitude (the International Dateline), and proceed westward in 3-day increments. Thus, countries located between 180 and 144 degrees east longitude will pick a night from April 1-3 for their public night of observation. Countries located between 144 and 108 degrees will have the April 4-6 time-slot, and so forth. In this way, through the month, the starry-night experience will progress around the globe westward in ten stages, creating a global star peace!

More details here: www.astronomerswithoutborders.org/index.php/projects/global-astronomy-month/news/news-features/263-30-nights-of-starpeace.html

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 ……….

World wide Astronomy Event – Advanced Warning

If you enjoy worldwide astronomy events, watch out for Global Astronomy Month (GAM), running throughout April of this year. The GAM motto is “One People, One Sky” and it’s an opportunity to connect with people around the world.

For more information take a look here: www.astronomerswithoutborders.org/index.php?option=com_content&view=category&id=99&layout=blog&Itemid=149
Image credit: Astronomer’s Without Borders

Asteroid Hunting

If you have a pair of binoculars or even a small telescope, you could try and follow an asteroid, Vesta, as it slowly move across the sky. The asteroid can be found in the constellation of Leo, not too far from Gamma Leo.

Happy Hunting

Image credit: Sky & Telescope

Comet Hunting

Note: this post is adapted from Weekend SkyWatcher's Forecast by Tammy Plotner on Universe Today, http://www.universetoday.com/

If you are ready for a challenge why not try spotting 11.8 magnitude Comet Tritton! Now cruising through the constellation of Aries (RA 1h 53.5m Dec 17° 39'), this faint fuzzy won't be the easiest of targets to spot – but then it wouldn't be a challenge, would it? Comet 157P Tritton was discovered by Keith Tritton (U. K. Schmidt Telescope Unit, Coonabarabran) on February 11, 1978. Now, almost 32 years later to the date, it's back again on its every 6.33 year journey around our Sun. Although it won't reach perihelion (closest position to the sun) until February 20, its original estimated return brightness was only expected to reach magnitude 16 and now it is far exceeding expectations. Don't expect to see a flaming ball exhibiting a tail because that's not going to happen… but congratulate yourself if you can find this faint fuzzy in the sky.

Image credit: Universe Today

Mars

If you have been out looking at the sky between about 8h00 pm and 9h00 pm, you may have noticed a particularly bright orange/red star slightly to your west (to your left when looking south) and quite “high” in the sky - this is not a star, it’s the planet Mars, the red planet!

If you have a pair of binoculars you may be able to make out the “disc” of the planet and with even a small telescope you should be able to see the white pole cap.

As well a this, Mars is quite close to an open star cluster (M44) and if you take a look over a few nights you should be able to spot Mar’s movement against the background stars.

Image credit: spaceweather.com

Full Moon Experiment

If your skies are clear tonight, January 29, take advantage of one of the sky watching highlights of the year. A full Moon and Mars will be putting on a show, and the pair will be prominently close to each other in the sky. Plus, this Friday night's full Moon is the biggest and brightest full Moon of the year. It's a "perigee Moon," as much as 14% wider and 30% brighter than other full Moons you'll see later in 2010.

If you have a camera try taking a photo of this full moon and then the next couple of full moons (you’ll need to make sure you keep the camera “settings” the same each time); you should be able to see the difference in the “apparent” diameters .

For more information take a look here: www.universetoday.com/2010/01/28/

Image credit: Universe today - McDonald Observatory

The Moon's Seas

A couple of days either side of the full moon is a good opportunity to try and take a look at all the moon’s seas or lunar maria. What you are looking at are, of course, not seas in the conventional sense of the word, they are in fact large, dark, basaltic plains. The plains are less reflective than the mountains or "highlands" as a result of their iron-rich compositions, and hence appear dark (and sea-like) to the naked eye.

With a pair of binoculars you should be able to see eleven Seas and one Ocean; you may also be able to spot a couple of the larger craters such as Tycho or Copernicus. Bon voyage!

Photo credit: Wikipedia

Star Bright

In a previous posting we looked at the fact that not all stars are the same colour, this time we’ll take a look at their brightness. You will have noticed (I hope) that when looking at Orion, not all the stars are of the same brightness. Betelgeuse (top left) and Rigel (bottom right) are much brighter than the stars top right and bottom left which are in turn brighter than the three stars that make up the “belt”!

So, why are some brighter than others? Are they closer? Are they Bigger? Are they hotter? Are they all three? Take some time to think about it (and maybe look at some other stars) and we’ll talk about it in the next posting.

Image credit: Wikipedia - Mouser Williams

Seeing Double – the “Wow Factor”

If you managed to find the two double stars we talked about in an earlier post, here are a couple of double stars a little more difficult to locate, but with some “wow” factor.

Among the best of all double stars and relatively easy to find is the last star of the string of bright stars that helps make the constellation of Andromeda. The second magnitude star, Gamma (γ)Andromeda (Almach), is stunning through a telescope, even a small instrument showing a superb pair separated by a good 10 seconds of arc.

Another relatively easy to find is Eta Cassiopeia, this double has a nice contrast with stars having yellow and orange colours.


If you would like to learn more about double stars, take a look here: http://en.wikipedia.org/wiki/Double_star/wiki/Double_star

The moon – proper motion and apparent motion.

If you have been following the moon this week you should have noticed some interesting things, firstly it has “grown” from a very small crescent to a now “half moon”. Hopefully you will have also noticed that at the same time each night the moon was “higher” and further to the west (to your left when looking towards the moon), you may also have spotted that the moon was not in the same position with regards to the background stars – earlier this week the moon was not too far from a very bright star low on the horizon (the bright star was, and still is, in fact Jupiter) and now it’s a long way from Jupiter and much higher in the sky.

So, what’s been happening? As you know, the moon orbits around the earth (i.e. it has “proper” motion), corresponding to a movement relative to the background stars by an amount roughly equal to its own diameter each hour; this movement is from west to east i.e. the moon starts (as a new moon) low in the western sky and moves slowly “upwards” and eastwards. At the same time, due to the fact that the earth is turning on it’s own axis from west to east, the stars and the moon (and of course the sun) appear to move from east to west. It’s a bit like someone “walking up the down escalator” assuming the person is walking upwards slower than the escalator is going down, he or she will eventually arrive at the bottom of the escalator.

If you would like to know more about the motion of the moon, take a look here: http://en.wikipedia.org/wiki/Orbit_of_the_Moon


If you have a pair of binoculars you can take a look at some of the moons “seas”, you should be able to see (1) Sea of Crisis, (2) Sea of Fertility, (3) Sea of Nectar, (4) Sea of Tranquillity, (5) Sea of Serenity and (6) Sea of Cold.

Photo credit: The Universe Today

Seeing Double

Find the constellation of The Plough (also known as the Big Dipper, the Saucepan or the Wagon depending on which country you are in) and take a look at the second star of the “handle” of the saucepan; you should be able to make out a second, fainter, “companion” star. The two stars are sometimes called the "Horse and Rider," in fact the ability to resolve the two stars with the naked eye is often quoted as a test of eyesight.

Many of the stars in the sky are in fact double stars (or even triple or quadruple stars), although not as easy to see as the example above. Many, however, can be seen in a small telescope or even in a pair of binoculars.

What is particularly interesting (and often quite spectacular) is the fact that many of the double stars are often two different colours, yellow and green, or orange and blue for example.

Here are a couple of double stars relatively easy to find.

The Pole star (Polaris) is a very easy double and can be seen in any small instrument
Rigel the bright star bottom right in the constellation of Orion is also easy

In another post we’ll look at some double stars a little more difficult to find, but when you find them or show them to others you will undoubtedly here “wow”!

Photo credit: Wikipedia

Watching the Moon

This is an excellent week to follow the moon as it travels across the sky, if you take a look at its shape and position over a number of nights (to the end of the week for example), you should notice some interesting changes. Here's what you need to do:

Take a look at the moon at the same time each evening (between 8pm and 9pm would be good) and note the following:

• The shape or form of the moon
• The position of the moon in the sky (high, low, above a tree or a building, etc)
• The position of the moon with regards to nearby stars (to the left/right of a bright star, between two bright stars, etc.

When you've done that over a week you should be able to distinguish between the "apparent" motion of the moon and the "proper" motion of the moon, but we'll discuss that at the end of the week.

Photo credit: Bob Larcher (photo taken with a digital camera "hand-held" in front of the eye piece of an 8 inch reflector

Star colours

Did you get to take a look at the stars? Here's what you should have seen, Betelgeuse (top left of Orion) is a reddish star, Rigel (bottom right of Orion) is a bluish star, Aldeberan (found by the following the imaginary line through the "belt" upwards to the right) has a distinct orange tint to it and Sirius (found by the following the imaginary line through the "belt" downwards to the left) is white - yes there are white stars! There are also yellow stars, green stars and stars of almost all the colours of the rainbow!

So why are stars different colours? In short it's linked to their temperature, blue and white stars being extremely hot and red and orange being somewhat cooler, although still very hot!

If you would like to know more about the colours, temperatures and sizes of stars, take a look here: http://en.wikipedia.org/wiki/Star

What colour are stars?

If you asked someone what colour stars are, they would probably say white, and they wouldn't be wrong; however, not all stars are white.

Go and take a look at the stars we have been talking about in previous postings; Betelgeuse (top left of Orion), Rigel (bottom right of Orion), Aldeberan (found by the following the imaginary line through the "belt" upwards to the right) and Sirius (found by the following the imaginary line through the "belt" downwards to the left).

Take a good careful look at these stars and in the next posting we'll talk about theirs colours!

Orion - a signpost in the sky

Orion is an excellent constellation to use as a starting point to find some interesting objects in the sky. Draw an imaginary line through the three stars that make up the belt; now follow this line downwards (bottom left) and you should come to an extremely bright star – in fact it’s the brightest star in the sky and it’s name is Sirius or “the dog star”, it is in the constellation of The Great Hunting Dog. Not only is Sirius very bright, but it is also one of our closest stars.

If you follow your imaginary line upwards (top right) you will come across another very bright star, this time it’s Aldeberan in the constellation of Taurus, the Bull. If you continue the imaginary line you will come across what looks like at first a small cloud, if you look carefully you should be able to see six (or if you have a really dark sky) seven stars, this is an open star cluster called the Pleiades or the Seven Sisters – with a pair of binoculars you should be able to see 20 or so stars.

Another imaginary line left (eastwards) across the two shoulder stars indicates the direction of Procyon in the Small Hunting Dog, and a final line from Rigel through Betelgeuse points to Castor and Pollux the two main stars of the constellation of Gemini or the Twins.

You should now be able to find 7 of the brightest stars in the sky and one of the most impressive open star clusters.

Have fun!

Image credit: Wikipedia

Orion

This is a great time of the year to see one of the largest and most spectacular constellations in the sky – Orion, the hunter. It is extremely easy to locate, simply go outside at about 9 pm, face south, look up to about 45° degrees above the horizon and there it is! The first thing that should strike you is the three bright stars in a row from “bottom left to top right”, this is the hunter’s belt and is in the middle of the constellation; surrounding the belt at roughly similar distances are four bright stars, which are considered to represent the outline of the hunter's body, and, descending from the 'belt' is a smaller line of three stars (the middle of which is in fact not a star but the Orion Nebula), known as the hunter's 'sword'.

If you have a pair of binoculars, take a look at the sword and you should be able to see the “hazy” form of the Orion nebula – an area where new stars are being formed!

Orion contains two of the brightest stars in the sky, above and to the left of the belt you will find a reddish star called Betelgeuse and below and to the right of the belt you will find a bluish star called Rigel.

In the next posting we’ll see how Orion can be used to find some other interesting objects in the sky.

If you would like to learn more about Orion, take a look here: http://en.wikipedia.org/wiki/Orion_(constellation)

Close approach of the moon to Antares

If you are up before the sun on the morning of 11 January, take a look eastwards and you'll see the moon very close to Antares the brightest star in the constellation of the Scorpion. If you have a pair of binoculars you may also be able to see M4 an open star cluster.

For more information about M4, take a look here: www.seds.org/messier/m/m004.html

From the Big Dipper to the Southern Cross

If you cannot get out to observe because of bad weather don't forget the second session of the project "From the Big Dipper to the Southern Cross" on the 10th of January, the project intends to bring the two hemispheres together - truly One People, One Sky! For this project there will be two telescopes - one in the northern hemisphere and one in the south - on two different nights. No experience is needed. This is a chance to watch as an experienced telescope operator and guide show how they capture the wonders of the night sky. Join other members of AWB Affiliates around the world. Chat will be available between participants and with the telescope operator. Join in or just watch - should make excellent armchair astronomy!

For more information take a look at http://www.astronomerswithoutborders.org/.

Observational idea - Melotte 20

If you are looking for something relatively easy to show to people why not try Melotte 20 (also known as Collinder 39); this is an open cluster centred around the star Alpha Persei (or Algenib), the brightest star in the constellation of Perseus.

The cluster can be seen with the naked eye if you have a really dark sky, otherwise a pair of binoculars will show it in all its glory.

For more information about Melotte 20, take a look here: www.seds.org/messier/xtra/ngc/alphaper.html

From the Big Dipper to the Southern Cross

Scheduled for the 8th and the 10th of January, the "From the Big Dipper to the Southern Cross" project intends to bring the two hemispheres together - truly One People, One Sky!

For this project there will be two telescopes - one in the northern hemisphere and one in the south - on two different nights. No experience is needed. This is a chance to watch as an experienced telescope operator and guide show how they capture the wonders of the night sky.

Join other members of AWB Affiliates around the world. Chat will be available between participants and with the telescope operator. Join in or just watch.

For more information take a look at www.astronomerswithoutborders.org.

The observational blog site for the EAAE

Dear readers

As you know the EAAE is under big website transformations.
This blog has been built to provide observational alerts about astronomical events that can be seen during the following nights.
The responsible for this blog will be Bob Larcher an EAAE member that has a long term collaboration history with the French section of the EAAE and that is now part of the EAAE's webteam.

We hope you will enjoy it.