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However the retailer, which also owns the Darty chain in France, said that it expected its markets to be tough over the course of 2009. The retailer said that like-for-like sales between November 1 and January 8 fell by 5.5pc. Sales at Comet fell by 2.5pc, while like-for-like sales at Darty fell by 6.2pc. Analysts expected total like-for-like sales to drop by between 6.5pc and 8.8pc. Jean-Noel Labroue, Kesa's outgoing chief executive, said that sales over the Christmas period were "very tough". However he said that Comet in the UK delivered a particularly strong post-Christmas sales performance. "Overall our businesses continued to make good progress in stock and cash management," said Mr Labroue. "We are expecting the difficult economic environment to continue and we will remain particularly focused on maintaining our strong balance sheet including net cash at the end of April," he said. He added that Kesa gained market share over the period. Citi, the bank, said that Comet's strong performance stemmed from strong post-Christmas sales. The bank pointed out that when Comet's sales performance and its margin trends are blended together, the profit performance at the chain is down by 11.2pc over the 10 weeks to January 8. Investec, the broker, said that the retailer's Spanish division performed poorly. Meanwhile Seymour Pierce, the broker, said that Comet's sales imply a "much better" result than at the DSG International-owner rival Currys. However, the broker said that there is a "sting in the tale", as gross margins at Kesa are expected to be down. Kesa's shares fell by 2.2pc to 89.75p.

Naked Eye Comets
There are no comets bright enough to be seen without binoculars or a telescope.Binocular Comets Comet C/2008 A1 (McNaught) Comet McNaught is a long-period comet that will passed closest to the Sun on Sept 29 at a distance of 1.07 AU (100 million miles or 160 million km). It was the first comet discovered in 2008 having been found by  Robert McNaught of the Siding Spring Survey back on Jan 10. It was McNaught’s 43rd comet discovery.The comet is only visible from the Northern Hmisphere and during November it crosses the constellation of Ophiuchus. The comet will slowly fade from magnitude 7.5 to 8.5 during the month. I was able to observe this comet with my 12″ Dobsonian from my backyard in Tucson. The comet was not an easy object to see even in a large telescope from a site with moderate light pollution. Dark skies will definitely help with this one. From dark skies, it can be seen in binoculars or a small telescope. From brighter skies, a telescope is required. A finder chart for Comet McNaught can be found at Comet Chasing. Small Telescope Comets Comet 6P/d’ArrestComet 6P/d’Arrest was one of the first short-period comets to be observed. First seen by the Frenchman Philippe de la Hire in 1678, the comet was definitively discovered by Heinrich Louis d’Arrest of Germany on 1851 June 28.Comet d’Arrest is in a short-period orbit with a period of 6.5 years. It passed closest to the Sun back on Aug 14 at a distance of 1.35 AU (125 million miles or 200 million km). The comet is a very difficult object for observers in the Northern Hemisphere because it is located in the southern constellation of Sculptor. Even though it will slowly move north this month, observing conditions will not improve because the comet will also fade from magnitude ~9.5 to ~11.0 by month’s end. This comet will definitely require a telescope and dark skies to be seen. A finder chart for Comet d’Arrest can be found at Comet Chasing. A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Summer
The day the north pole is nearest the Sun is called the 'summer solstice'. (You can see this from the picture on the right). Looking from Earth, the Sun reaches its highest point in the sky all year. This means it takes the most amount of time to cross the sky. So this is the longest day of the year and happens around 21 June. Astronomers call this the start of summer and after this date, days start getting shorter.AutumnAs we continue our journey around the Sun, the north pole moves away from the Sun. The Sun rises lower in the sky so the days continue getting shorter. When the Sun is at its mid-point in the sky, we reach the 'autumn equinox', around 22 September. Day and night are both 12 hours long and its the beginning of autumn.Winter The day when the north pole is furthest from the Sun is called the 'winter solstice'. The Sun crosses the sky at its lowest point all year. Therefore it crosses the sky in the quickest time so this is the shortest day of the year. Winter solstice happens around 22 December and marks the start of winter. From then on, the days start getting longer.SpringThe Earth continues on its path, and our north pole starts moving towards the Sun again. The Sun moves upwards in our skies and the days continue getting longer. Again, we reach a midpoint when day and night are both 12 hours long. This is called the 'vernal (or spring) equinox' and happens around 21 March.

We switch now to the region beyond Earth, as we explore the Mysterious Planet Mars, recently upgraded in interest because of the discovery of possible evidence of single-celled, organic matter (life?) in a meteorite (found in the Antarctic), believed to have been ejected into deep space from an impact on ancient Martian crust. Mars has always been especially intriguing to the peoples of Earth. It has captured our imagination for many reasons, two of which are the once-believed speculation that it held intelligent life because of so-called "canals" and then the famous book by H.G. Wells, "The War of the Worlds", that had martians invading Earth (this was the basis for the "infamous" radio program by Orson Welles that was so realistic that people panicked during the broadcast). Mars is about half the size of Earth, evident in this picture in which the two planets are shown side by side at the same size scale:

The Moon: Lunar Prospecting With Chandra

The Chandra observations (right) of the bright portion of the Moon detected X-rays from oxygen, magnesium, aluminum and silicon atoms. The X-rays are produced by fluorescence when solar X-rays bombard the Moon's surface.According to the currently popular "giant impact" theory for the formation of the Moon, a body about the size of Mars collided with the Earth about 4.5 billion years ago. This impact flung molten debris from the mantle of both the Earth and the impactor into orbit around the Earth. Over the course of tens of millions of years, the debris stuck together to form the Moon. Measuring the amount and distribution of aluminum and other elements over a wide area of the Moon will help to test the giant impact theory.Chandra's observations have also solved a decade-long mystery about X-rays detected by ROSAT that were thought to be coming from the dark portion of the Moon. It turns out that these X-rays only appear to come from the Moon. Chandra shows that the X-rays from the dark moon can be explained by radiation from Earth's geocorona (extended outer atmosphere) through which orbiting spacecraft move.The geocoronal X-rays are caused by collisions of heavy ions of carbon, oxygen and neon in the solar wind with hydrogen atoms located tens of thousands of miles above the surface of Earth. During the collisions, the solar ions capture electrons from hydrogen atoms. The solar ions then kick out X-rays as the captured electrons drop to lower energy states.

The Comet Hale-Bopp and Andromeda

Hale-Bopp over the Mountains

Hale-Bopp over "Cinque Torri"

Explanation: Comet Hale-Bopp, the Great Comet of 1997, was quite a sight. No comets of comparable brightness have graced the skies of Earth since then. During this next month, however, even besides the fleeting Comet Bradfield, two comets have a slight chance of rivaling Hale-Bopp and a good chance of putting on a memorable sky show. Unfortunatetly, most of the show will be confined to sky gazers in Earth's southern hemisphere. Both comets are already visible to the unaided eye from there. The first, Comet C/2002 T7 (LINEAR), should be at its best before dawn during the first weeks of May from the south. The second, Comet C/2001 Q4 (NEAT), should be visible in early May from all over the Earth. Both comets appear to be approaching the inner Solar System for the first time and so it is very hard to predict how bright each will become. In the above photograph taken 1997 April 6, Comet Hale-Bopp was imaged from the Indian Cove Campground in the Joshua Tree National Forest in California, USA. A flashlight was used to momentarily illuminate foreground rocks during this six minute exposure.

Great Comet Hyakutake highlighted 1996 with an amazing celestial display, but not only was the show that the comet put on spectacular, but the new information regarding the make-up and emission properties of comets was just as spectacular to those within the scientific community. Although Hyakutake’s bright life span was short, it will continue to be one of the most celebrated cometary events of the last century and the data garnered from the study of this comet will continue to influence cometary research until such earthbound research is no longer necessary.

The Chandra observations (right) of the bright portion of the Moon detected X-rays from oxygen, magnesium, aluminum and silicon atoms. The X-rays are produced by fluorescence when solar X-rays bombard the Moon's surface.According to the currently popular "giant impact" theory for the formation of the Moon, a body about the size of Mars collided with the Earth about 4.5 billion years ago. This impact flung molten debris from the mantle of both the Earth and the impactor into orbit around the Earth. Over the course of tens of millions of years, the debris stuck together to form the Moon. Measuring the amount and distribution of aluminum and other elements over a wide area of the Moon will help to test the giant impact theory.Chandra's observations have also solved a decade-long mystery about X-rays detected by ROSAT that were thought to be coming from the dark portion of the Moon. It turns out that these X-rays only appear to come from the Moon. Chandra shows that the X-rays from the dark moon can be explained by radiation from Earth's geocorona (extended outer atmosphere) through which orbiting spacecraft move.The geocoronal X-rays are caused by collisions of heavy ions of carbon, oxygen and neon in the solar wind with hydrogen atoms located tens of thousands of miles above the surface of Earth. During the collisions, the solar ions capture electrons from hydrogen atoms. The solar ions then kick out X-rays as the captured electrons drop to lower energy states.