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 is a partial lunar eclipse on 5 July.

The Earth is at aphelion on 4 July. As seen from the Earth, the Sun is moving from the constellation Gemini to the constellation Cancer.

The phases of the Moon are

Full : 5 July
Last Quarter : 13 July
New : 20 July
First Quarter : 27 July

The Moon is at apogee on 9 July and at perigee on 21 July.

The Moon occults four planets this month but each event occurs during daylight hours. Saturn disappears first on 17 July, followed by Venus a few hours later. Two days later, both Jupiter and Mercury slide behind the lunar disc.

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
The smallest of the inner planets reaches greatest elongation west on on 9 July. Look for it in the eastern sky just before sunrise. Mercury can be found in the constellations Taurus, Orion, Gemini and Cancer.
Venus
Venus is the brilliant "morning star" in the east. It is getting lower for southern observers but continues to climb higher in the dawn sky for those in the northern hemisphere. Look for it in the constellations Taurus and Orion.
Mars
The red planet resumes prograde motion on 19 July and is visible until after midnight in the constellation Ophiuchus. The bright star nearby is Antares. How do the colours compare?
Jupiter
You will need to get up before the Sun in order to view Jupiter in constellations Taurus and Gemini.
Saturn
Saturn can be found not far from Jupiter in the constellation Taurus.
Uranus
Uranus is up nearly all night in the constellation Capricornus.
Neptune
The blue gas giant is at opposition on 30 July so it can be seen all night (with a telescope) in the constellation Capricornus.
Pluto
Pluto sets early in the morning in the constellation Ophiuchus. However, because it is so small and faint, a large telescope is always needed to see it.

Minor Planets, Comets and Meteors

Minor Planets
On 7 July, 1 Ceres will be at opposition in the constellation Sagittarius but at only seventh magnitude, optical aids will be needed to see it.
Comets
There are no naked-eye comets visible this month.
Meteors
The delta Aquariids peak on 28 July. The waxing Moon may cause some interference.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union (IAU) recognises 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...

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. Used with permission.

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Last modified on 30 June 2001
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