Welcome to the

Established 10^th August 2000

h2g2as Front Page	The main site page.
Heads Up	What to see in the coming month.
Moonwatching	Observing the Moon for Lunartics.
Messier Marathon	Hunt the 110 fuzzy lights
Members Page	Meet the researchers who have joined the h2g2as and join up yourself.
Constellations Project	The H2G2 Hitchhiker's road-map.
h2g2as Q and A	Find the answers to many space related questions.
Astronomy Links	Find all the best astronomy links as well as links to local societies.
Previous Articles	Contained here are some of the previous news headlines from the front page.
Babe Among the Stars	Galaxy Babe's column in The Post.

This is one of the places on h2 where you can read about events that will take place during the coming month. We're afraid that the information here is slightly biased toward Northern Hemisphere Researchers, but if there are any southern sky stargazers out there, we'll be happy to include sky updates for the heavens 'down under'. For a slightly 'different' view on things Astronomical, there is a another port of call at A/S's Galaxy Babe's own column in h2g2's 'The Post', 'Babe Among the Stars'.

	The Coming Month: December 2009

Updated 6 Dec 2009

	Two for the Price of One

Two full moons occur during December. The first is 2 December. Fittingly, the second is on the last day of the month, 31 December. So, if you happen to be outside first footing, or just taking the waters in Trafalgar Square, and it happens to be a clear night, take a look southward and upwards. You can be rewarded with one of natures most beautiful sights.

	International Year of Astronomy: IYA

The International Year of Astronomy comes to a close at the end of the year. There are plans to carry on with the good work and build on the interest kindled by the activities that were played out during the year. Plans to introduce astronomy and science to those that may find an interest in it are afoot.

	LCROSS: For One Day Only

On the 9 October the Centaur booster rocket, from the lunar mapping satellite LCROSS, impacted with the Moon. Directed at one of the permanently shaded craters at the Moon’s south pole it was expected to throw up a plume of debris that can be sampled by the following LCROSS satellite on the same trajectory, and analysed just before it too, impacts. Its purpose was to determine, once and for all, if there is water lurking in the shadowed craters.

In the event the resulting debris plume was something less than spectacular. In fact even the heat flash was only seen with the aid of computerised technology. Even though the visual effects were unspectacular, the physical data retrieved was analysed and a significant quantity of water was found. Although the amount was not a great deal.

	Lunar Phases for December

The following table lists the major lunar phases for the coming month. (December 2009)

Full Moon	Last Quarter	New Moon	First Quarter	Blue Moon
2 December	8 December	16 December	24 December	31 December

Partial Lunar Eclipse

On the night of the second full moon of the month, 31 Dec, (A Blue Moon to some) there will be a partial eclipse of the Moon about 2 hours either side of 19.20 U/T. For UK observers the Moon will only show a slight darkening as it passes through the Earths penumbra. Observers further south will get a better view

	The Planets

Fast moving Mercury is close in to the Sun during the first half of the month. It gradually moves away until it gets to its furthest elongation around the 24 Dec when it will be best seen just after sunset, but only about 5 degrees above the horizon.

Venus has moved around to the far side of the Sun and during most of the month is lost in its glare.

Mars is now rising in the late evening and by midnight is becoming more prominent. On the 7 Dec it is passed by the near third quarter moon.

Jupiter is still observable due south through the early evening, but only about 15 - 20 deg above the horizon from the UK. Its four major moons can be tracked quite easily with binoculars or small telescope. This month, in the same way that Saturn's rings are edge on to us, so is the plane of the galilaen moons. This can bring about the unusual occultation of one moon by another. On Dec 7, seen from the UK Europa occults Io at 22h 05 U/T. You won't have to blink though as the whole passing takes only four minutes. From the US on Dec 14, Europa occults Io at 7.26 PM EST and on 12 Dec Ganymede occults Europa at 7.49 PM EST.

Saturn is still in Virgo during December and is viewable after rising around midnight.Its rings are now almost edge on to us and have all but disappeared as they turn fully edge on as viewed from Earth with a significant loss of magnitude It can be found up to 30 degrees above the horizon.

Uranus trails about 30.0 degrees east of Neptune and Jupiter along the ecliptic.

Neptune is in the same binocular field as Jupiter. This month only a degree or so seperates them. Being the dimmest of the planets it's not easy to spot without at least binoculars but Jupiter makes a good signpost for it.

	Meteor Showers

Two meteor showers this month. The maximum for the Geminids occurs on the night of the 13 - 14 Dec, and the maximum for the Ursids on the 21-22 Dec. Of the two the Geminids are likely to be the most prolific. In the past up to 100 per hour have been recorded.

	The International Space Station (ISS)

Although not strictly astronomy, would you like to spot the ISS? It's perfectly possible but you have to be in the right place at the right time. It orbits the Earth every 92 minutes travelling at 7.68 km per second. Its orbit is inclined to that of the Earths by 52.6 degrees. That means that it passes over most of the Earth's surface. Its orbit and the time that it passes over any given point is therefore predictable.

To the casual observer the ISS is only visible when it is illuminated by the Sun and the observer is standing on the dark side of the nightline. For all practical purposes this means just after sunset or just before dawn. Although the computations are formidable, happily we have a website available that will do the calcs for you. Click on Heavens Above to insert your location and the site will show the predicted local overflys of the ISS.

Just as an example, the table below shows predicted passes by the ISS centred over Folkstone UK. Not all passes are listed, just the brightest and those with the best chance of observing. Currently they are very early morning, but are likely to shift to late evening in the near future. To be updated.

Calendar of Meteor Showers

Most of the major meteor showers occur at or around the same time every year. The following is a handy list of some of the big ones, along with the approximate date listed for peak activity. It should be remembered that the meteors per hour figure is an approximation based on past showers' activity. Actual results may vary.

Date	Meteor Shower	Meteors Per Hour
January 3	Quadrantids	40
April 21	Lyrids	15
May 4	Eta Aquarids	20
July 28	Delta Aquarids	20
August 12	Perseids	50
October 21	Orionids	25
November 3	South Taurids	15
November 17	Leonids	15
December 13	Geminids	50
December 22	Ursids	15

The Messier Marathon

Charles Messier, astronomer to the French court of King Louis XV produced a list of objects observable in the night sky that were to be avoided so that they would not be confused with his main pre-occupation, comets. The Messier list contains 110 objects that perversely are some of the most interesting objects in the night sky and are definitely not comets. During the latter part of March each year, all 110 are observable between dusk and dawn during the course of a single night. This year, 2009, many dedicated Marathoners tried their luck during the weekend of 28/29 March, but here at H2 we tend to be a bit more flexible. On the Messier Marathon Page you can start your own marathon to run as long as you want it to. To set your own time limit to view the famous 110 just start a convo there and we'll record the running total as you go along.

Measurements in the Sky

From time to time, we make describe the distance between objects in the sky in degrees. Here's a quick rule of thumb guide to help you understand what we're talking about:

• The sky is 180 degrees from horizon to horizon. A degree can further be divided into 60 arcminutes and an acrminute can be divided into 60 arcseconds.
• For reference, both the Sun and the Full Moon are each half a degree, or 30 arcminutes in diameter.
• At arm's length, the distance across the knuckles of a clenched fist covers 10 degrees.
• The stars in Ursa Major which point toward Polaris (the North Star) are 5 degrees apart.

	Share Your Wisdom

Check out the Department of Astronomy as part of a great collaborative effort at the h2g2 University. There are a lot of great entries being written there on a variety of astronomical topics. The idea behind the University project is to create subtopics of information in a broader category - like Astronomy. And to do so in a specified time period. Everyone is invited so stop by!

	Fight Light Pollution

Why not ask your local zoning authority if there are any restrictions on light pollution where you live. Bright parking lot lights will eventually fill the night sky with a dull haze of background light, ruining the chances of seeing the stars! To join the fight to save dark skies, go the International Dark Sky Association.

If you don't think there's a light pollution in your area, go outside and look at the Big Dipper.¹ You should see a double star in the handle, second star up from the end. That is Alcor and Mizar. If you can't see them, you either need glasses or you've got a light pollution problem!

Join the fight - turn off that outside light!

	Join the H2G2 Astronomy Society

H2G2 Astronomy Society which carries the latest astronomical news as well as linking to many of the astronomical entries on h2g2. It's also a great place to hang out and chat with fellow Researchers about astronomical topics which interest you.

	Search for Extraterrestrial Intelligence

Are we alone in the universe?
Who knows, but now, you can join the search for extraterrestrial life with a few dozen guide researchers who have joined together to help the SETI team. For more information you can go to the h2g2 SETI@home page.

	Picture of the Day

You can click on this link to find the NASA Picture of the Day. This link is pretty cool - in addition to an interesting astronomical photo, there is a brief explanation of what you're seeing. American tax dollars at work!

	Check out the BBC's pages

BBC Online's Space pages, including a 3-D tour of the Solar System, a user submitted photo gallery, a quiz and up-to-date news. It's definitely worth checking out! UK license fees at work!