SkyEye

Welcome to SkyEye, your guide to this month's celestial events. All dates are based on Universal Time (UT).

The Sun and Moon

There are no eclipses this month. As seen from the Earth, the Sun is moving from the constellation Aries to the constellation Taurus.

The phases of the Moon are

Last Quarter : 8 May
New : 15 May
First Quarter : 22 May
Full : 30 May

The Moon is at apogee on 2 May, at perigee on 15 May, and at apogee again on 29 May. People living in coastal areas should take extra care on 15 May as the New Moon at perigee should raise particularly high tides.

The Moon occults two planets and two first-magnitude stars in May. Like last month, Neptune and Uranus are occulted a day apart. The first to go is Neptune on 7 May. Observers in Japan may witness this event during darkness at approximately 17 UT. It will be daylight by the time the occultation is visible in Alaska and western Canada. The next day, during daylight hours, Uranus will glide behind the limb of the Moon for observers in Alaska, Canada, and the lower 48 states of the United States. A daytime occultation of Aldebaran occurs for Arctic observers on 16 May. Finally, at 3 UT on 22 May, Regulus will disappear from view during daylight hours in northeastern Asia and Alaska. However, the skies will be dark in Canada and most of the rest of the United States for this event.

The Planets

The word planet is derived from the Greek word for "wanderer." Unlike the background stars, planets seem to move around the sky, keeping mostly to a narrow track called the ecliptic, the path of the Sun across the stars.
Mercury
On the first of the month, Mercury races past Jupiter. Saturn is its next port of call on 18 May. This closest of all planets to the Sun then reaches superior conjunction on 25 May. It is falling out of the morning sky and will be invisible (too close to the Sun) by mid-month. Best seen in the southern hemisphere this month, it can be found in the constellations Pisces, Aries, and Taurus.
Venus
The northern hemisphere gets the best views of Venus as the "evening star" in the western sky after sunset, and the situation is improving for southern hemisphere observers as this bright planet begins to climb more quickly into the sky. Look for Venus in the constellations Taurus and Gemini.
Mars
This is still the best time to observe the red planet. Mars reached opposition late last month and on 1 May, is at its closest to Earth. Up most of the night, it can be found in the constellation Virgo.
Jupiter
On the first day of the month, Jupiter can be found quite close to Mercury in the sky. A special event which occurs only once every twelve years happens on 19 May when Jupiter reaches perihelion. This is the point in Jupiter's orbit that is closest to the Sun. The largest of all planets in the solar system rises as Mars sets. Look for it in the faint constellation Pisces.
Saturn
Like Jupiter, the ringed planet also has a close encounter with Mercury, this time on 13 May. Saturn rises shortly after Jupiter and can be found in the constellation Aries.
Uranus
Uranus is at west quadrature on 7 May and is occulted by the Moon on the following day. It begins retrograde motion on 22 May. At best just on the edge of naked-eye visibility, it rises around midnight with Neptune in the constellation Capricornus.
Neptune
Neptune also has an encounter with the Moon although it happens the day before the Uranus occultation. The day before that, on 6 May, Neptune begins retrograding. Neptune is falling behind Uranus after their triple conjunction in 1993, but they are still found close together in the sky. Look for this distant gas giant in the constellation Capricornus.
Pluto
On the last day of the month, Pluto reaches opposition. However, because it is so small and faint, a large telescope is always needed to see it. The outermost planet in the solar system is up all night in the constellation Ophiuchus.

Minor Planets, Comets and Meteors

Minor Planets
3 Juno, the third minor planet discovered, is at opposition on 25 May. At its brightest it is only tenth magnitude so a telescope will be needed to see it in the constellations Ophiuchus and Serpens (Caput).
Comets
There are no naked-eye comets visible this month.
Meteors
On 6 May the Eta Aquariids reach their peak of activity. Best observed in the southern hemisphere, the waning Moon may provide strong interference.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union (IAU) recognizes 88 different constellations. The brightest stars as seen from the Earth are easy to spot but do you know their proper names? With a set of binoculars you can look for fainter objects such as nebulae and galaxies or some of the closest stars to the Sun.

Descriptions of the sky for observers in both the northern and southern hemispheres are available for the following times this month. Subtract one hour from your local time if daylight savings time is in effect. (Note: These times are approximate.)

Northern Hemisphere : 45° N

Southern Hemisphere : 30° S

For More Information...

Blue moons, eclipses, the dates of Easter and much more can be found at the Interactive Astronomy Pages. For more information about the objects and events described in SkyEye, visit these astronomy-related sites.

Credits

Much of this information can be found in this month's issue of Sky & Telescope and in other fine amateur astronomy magazines available in your local bookshop. Another excellent source is the current edition of the Astronomical Calendar by Guy Ottewell and published by the Universal Workshop at Furman University.

The image of the Sun in the SkyEye banner is courtesy of the SOHO/EIT consortium. SOHO is a project of international cooperation between ESA and NASA.

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