What to See & When

Here you can find information on;
  • Today's weather forecast for Guernsey
  • Monthly highlights with Sky Charts to help you visualise what celestial bodies are visible
  • Yearly information on the sun, moon, planets and meteors
  • A glossary of astronomical terms used in the various pages
Sky Charts generated by Sky Safari, Simulation Curriculum Corp.

Glossary

New Moon

The Moon is between the Earth and the Sun, so the bright side of the Moon is facing away from the Earth.

Supermoon

So-called ‘supermoons’ occur when the Full Moon happens to coincide with the Moon’s closest approach to Earth (‘perigee’), and therefore appear larger than usual.

Vernal Equinox

In the Northern Hemisphere the vernal equinox falls about March 20 or 21, as the Sun crosses the celestial equator going north. According to the astronomical definition of the seasons, the vernal equinox also marks the beginning of spring, which lasts until the summer solstice (June 20 or 21 in the Northern Hemisphere.

Conjunction

Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space.

Elongation

In astronomy, a planet's elongation is the angular separation between the Sun and the planet, with Earth as the reference point. The greatest elongation of a given inferior planet occurs when this planet's position, in its orbital path around the Sun, is at tangent to the observer on Earth.

Opposition

Two astronomical objects are said to be in opposition when they are on opposite sides of the celestial sphere, as observed from a given body. A planet is said to be "in opposition" when it is in opposition to the Sun.

Perihelion

The perihelion and aphelion are the nearest and farthest points respectively of a body's direct orbit around the Sun.

Penumbra

The partially shaded outer region of the shadow cast by an opaque object, i.e. the Earth

Penumbral Lunar Eclipse

Only the more diffuse outer shadow of Earth, the penumbra, falls on the moon’s face.