In order of distance from the Sun, the planet Mercury comes first, then Venus, and our Earth is the third rock…, as the saying goes. The paths of Mercury and Venus around the Sun are completely enclosed by the Earth's orbit and that is why Venus and Mercury are called the inferior planets, or sometimes the inferior planets. Arguably,Venus impresses us more forcibly than any other world, as a planet that is revolving around the Sun. This is because Venus approaches the Earth more closely than any of the major planets; and its apparent size changes strikingly in the telescope as it moves towards the Earth and then away from us in its journey through space.

Venus shows phases, like the Moon. It waxes from a large, slim crescent when it is near the Earth, to a small, round disc when it is far away on the opposite side of the Sun. And its phase wanes as it approaches the Earth once again. Thus we are truly aware of three-dimensional phenomena over the weeks and months while we observe this fascinating planet.

Venus is the brightest planet in our sky. Its cloudy atmosphere efficiently reflects the light it receives from the Sun and it is an Earth sized world that is relatively close by in space. In the dark dawn and the deep dusk the fierce glare of Venus overpowers all but the very best optics. Seen in the telescope by day in a calm sky she is bright and serene. The sight may be enhanced by the occasional floating sunlit seed or by the flight of a dark insect across the field of view. This is the exciting spectacle that awaits the telescopic observer.

When Venus is lined up in between the Sun and the Earth, Venus is said to be at inferior conjunction. The line up is not usually exact at these times and, telescopically, Venus will appear as a filamentary crescent a few degrees north or south of the Sun in the sky. Given good observing conditions the planet's cusps may be seen to extend beyond a half circle. The cusps are the north and south parts of the disc - the horns of the crescent phase. Cusp extension is a twilight effect caused by diffused sunlight in the planet's atmosphere. When close to inferior conjunction observers sometimes see Venus completely encircled by this twilight arc. Inferior conjunction is for experienced observers only.

Venus reached inferior conjunction on 1999 August 20. On that day Venus appeared to pass about 8 degrees south of the Sun in the sky. The veteran planetary observer Walter Haas, Las Cruces, New Mexico, reported sightings of the complete ring of light on each day from August 16 to August 21 and again on the 23rd and the 25th. Mario Frassati, Crescentino, Italy, and Robert Steele, Leeds, UK glimpsed cusp extensions.

Alan Heath captured the sight on 1999 September 18 at 05.30 UT. Note the narrow, bright cusp caps and the three dark spots next to the terminator. The terminator is the division between the bright sunlit crescent and the dark part of the planet that faces away from the Sun. When Venus is a crescent, like this, irregularities and dusky or bright areas are sometimes noted along the terminator. 20cm Schmidt Cassegrain, x200, seeing conditions rated as fair, Long Eaton, Nottingham.

Conditions for observing were very good for Northern Hemisphere observers in the autumn of 1999. From September through to November Venus rose steeply above the south-eastern horizon as it moved through the constellations of Cancer, Leo and Virgo. Henry McEwan, this section's first Director, noted very similar conditions in 1913 when the planet's western, morning, elongation was the most interesting in his experience. ''During September, October, and November, the definition was almost ideal and it was concluded from observations that the planet does not appear to rotate rapidly, the few markings that were visible in the central part of the disc maintaining a fixed position relative to the terminator. These markings tended to appear streaky and apparently radiated from the central part of the visible disc next the terminator towards the limb, but disappeared half way. The existence of a brilliant white spot was observed at the southern part of the planet and this could not be distinguished from a snow cap.''
BAA Memoirs vol. 42, part1 at page 85, after HL Kelly.

 The ''snow cap'' of Venus has vanished in the light of modern knowledge. The cusp caps are now known to be swirls of bright cloud. But, a bright south cusp cap and streaky markings as seen then are reported by observers at the 1999 morning apparition under similarly good seeing conditions.

 The Ashen Light was also been reported on the morning of 1999 October 3 by the very experienced planetary observer, David Gray of Kirk Merrington, Co Durham. The ashen light is a faint illumination of the part of the planet facing away from the Sun. It resembles the Moon's ''Earthshine'' or ''the old Moon in the new Moon's arms'' that is a familiar sight when the Moon is at crescent phase. It is the Earth reflecting sunlight onto our nearby Moon that causes the Earthshine, but the cause of the Ashen Light for Venus is unknown.

The so-called phase anomaly is another interesting topic for the observer of Venus. It has long been known that the time when Venus shows a half phase in the telescope frequently occurs later than the predicted time when Venus is west of the sun; and half phase is earlier than expected when Venus is east of the Sun. The half phase is called dichotomy. The results of two observers are shown in this graph for autumn 1999. Both observers agree in timing dichotomy at 2^nd November 1999, approximately three days ''late''.

Key- solid line - theoretical phase, crosses - Alan Heath estimates, dots - RM Steele estimates. Both used W15 yellow filters.

 During December 1999 and January 2000 Venus became difficult to observe from the UK, because it was low in the sky where the seeing conditions were poor. Observers in more southerly latitudes were favoured because the planet rose higher above their horizons.

From March through to September 2000 Venus retreats to the far side of the Sun and its disc appears small in the telescope.

Venus is said to be at superior conjunction when farthest from the Earth with the Sun positioned in between both planets. As with inferior conjunction, the line up is not usually exact, but during June 2000 Venus actually passed directly behind the solar disc. This is technically known as an occultation. The opposite situation, when Venus passes directly in front of the Sun is known as a solar transit, or transit for short. Transits of Venus are extremely rare, the last one happened in 1882, but the next transit of Venus will take place on 2004 June 8.

Later this year Venus will return to the evening skies. Observers are invited to send drawings and notes to the BAA Mercury and Venus Section.