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NGC 6124, mag. +5.8, is a fine open cluster located in the constellation of Scorpius. It's faintly visible to the naked eye, appearing as a hazy unresolved patch of light, and a superb sight in binoculars and small telescopes. The cluster covers 29 arc minutes of apparent sky, which is equivalent to the apparent diameter of the full Moon. In total, NGC 6124 contains over 100 stars and is fully resolvable in large amateur scopes. This rewarding cluster would almost certainly be much better known if it weren't located at such a southerly declination.

NGC 6124 was discovered by Nicholas Louis de Lacaille during his 1751-1752 journey to South Africa. It's best seen from southern and equatorial locations during the months of May, June and July.

NGC 6124 (credit:- Roberto Mura)

NGC 5694, also known as Caldwell 66, is a faint globular cluster in the constellation Hydra. At mag. +10.2, it's not a bright object and the reason is simply due to its distant. At approx. 114,000 light-years, it's further away than the actual diameter of the Milky Way galaxy. However, despite this it can be spotted with amateur telescopes, although virtually impossible to resolve in most backyard instruments.

William Herschel discovered NGC 5694 on May 22, 1784. Even when using the best telescope of the day, Herschel couldn't resolve it into stars and catalogued it as a faint nebula. The object was first resolved and at the same time its true nature determined by Carl Lampland and Clyde Tombaugh in 1932. Recent measurements suggest that it's moving fast enough to eventually escape the galaxy and move into intergalactic space.

The cluster is best seen from southern and equatorial latitudes during the months of April, May and June.

NGC 7009, also known as the Saturn Nebula, is a famous planetary nebula in the constellation Aquarius. It has an apparent magnitude of +8.3 and therefore bright enough to be spotted with binoculars. Because of its high surface brightness, it's relatively easy to find and observe with virtually any type of telescope. Visually the planetary appears small and compact but when seen through larger scopes it somewhat resembles the planet Saturn, hence the nickname "Saturn Nebula". The 3rd Earl of Rosse, William Parsons, came up with the name in 1840.

The planetary is best seen during the months of July, August and September.

NGC 7009 (credit:- NASA, ESA, and The Hubble Heritage Team (STScI/AURA))

At the start of the year, periodic comet 45P/Honda-Mrkos-Pajdusakova was visible as an early evening object, low down at dusk above the western horizon. During February, it re-emerges in the morning sky and this time is much better placed for northern-based observers.

45P/Honda-Mrkos-Pajdusakova as imaged on October 1, 2011 (credit:- Martin Mobberley - www.martinmobberley.co.uk)

NGC 4449, also known as Caldwell 21, is an irregular galaxy located 12.5 million light-years away in the constellation Canes Venatici. It's part of the M94 Group (or Canes Venatici I Group), a galaxy group close to the Local Group. With an apparent magnitude of +9.4, it's within binocular range but challenging. The galaxy is much easier to spot with telescopes and a rewarding object due to its unusual appearance.

NGC 4449 is intrinsically similar in size and brightness to the Large Magellanic Cloud (LMC), but unlike the Large Magellanic Cloud, it's a starburst galaxy with a high rate of active star formation. It's believed that the current widespread starburst was triggered by interaction or merging of NGC 4449 with a smaller companion or companions. As a result, it contains numerous HII regions and several large star clusters, which contain thousands of young, hot blue stars.

William Herschel discovered the galaxy on April 27, 1788. It's best seen from Northern Hemisphere latitudes during the months of March, April and May.

Algol (β Per) is a bright eclipsing binary system located in the northern constellation of Perseus and one of the best-known variable stars in the sky. Often referred to as the "Demon Star" most of the time it shines at mag. +2.1 but every two days, 20 hours and 49 minutes the star suddenly dips in brightness to mag. +3.4, remaining dim for about 10 hours before returning to its original state.

Why the change in brightness? The Algol system consists of at least three-stars (β Per A, β Per B and β Per C) with the orbital plane of Algol A and B directly in line with the Earth. The regular dips in brightness occur when the dimmer B star moves in front of and eclipses the brighter A star. There is also an extra dimension in that a secondary eclipse occurs when the brighter star occults the fainter secondary resulting in a very small dip in brightness that can be detected with photo-electrical equipment.

Algol System (credit:- Dept. of Physics and Astronomy - Univ. of Tennessee at Knoxville)

Mercury

Mercury is now heading towards superior conjunction, which it reaches on March 6th. From southern and tropical regions, the planet is visible in the morning sky during the first half of February. However, it remains low down above the eastern horizon. For example, on February 1st, Mercury shines at mag. -0.2 and will be 7 degrees high, one hour before sunrise from mid-southern latitudes. Each subsequent morning, it falls slightly back towards the Sun until finally lost to the bright twilight glare during the second week of the month. From mid-latitude northern locations, it's not observable.

On February 7th, Mercury reaches aphelion when it will be 0.467 AU (approx. 69.9 million kilometres or 43.4 million miles) from the Sun.

Venus

Venus remains a brilliant evening object throughout the month. The planet shines as an unmissable beacon of light above the western horizon. On February 17th, greatest illumination occurs when it peaks at mag. -4.9, which is about as bright as it ever gets. Positioned about 6 degrees east of Venus is Mars (mag. +1.2).

NGC 6826 is a magnitude +8.8 planetary nebula located in northeastern Cygnus. It's a compact object that blinks on and off when observed, hence the name Blinking Planetary. Most planetary nebulae exhibit this type of behaviour but with NGC 6826 it's particularly obvious. When you look directly at the central star the nebula tends to fade away but glancing towards the edges - using averted vision - it suddenly re-appears. Switching back and forth rapidly between averted and direct vision causes the nebula to dramatically blink on and off.

NGC 6826 was discovered by William Herschel on Sep 6, 1793. It's number 15 in the Caldwell catalogue and is best seen from northern locations during the months of June, July, August.

NGC 6826 (credit:- NASA, ESA, and The Hubble Heritage Team (STScI/AURA))

NGC 7006 is a distant globular cluster, 135000 light-years away, in the constellation of Delphinus. The globular resides in the galactic halo region of the Milky Way, an area of space that contains relatively few clusters. Its actual size is slightly smaller than M13 - the best globular in the northern section of sky - but since it's 5 times further out, it shines at only mag. +10.6 and spans less than 3 arc minutes of apparent sky. The cluster is one of the most distant Milky Way globulars observable with backyard telescopes.

NGC 7006 was discovered by William Herschel on August 21, 1784 and is best seen during the months of July, August and September. It has a spatial diameter of 110 light-years and is estimated to contain 250,000 stars. It's listed as number 42 in the Caldwell catalogue.

NGC 7006 (credit:- NASA, ESA, and The Hubble Heritage Team (STScI/AURA))