28 March 2006
Watch the 2006 total eclipse with ESA
On Wednesday 29 March 2006, the Moon's shadow will sweep over the
surface of Earth during the fourth total solar eclipse of this century.
The path of the Moon's 'umbral' shadow begins in Brazil at 10:35 CEST
[0835 UTC] and crosses the Atlantic reaching Africa about 11:08 CEST
[0908 UTC], where it will travel over the northern part of the
continent. It next crosses the Mediterranean Sea to Turkey, and then
central Asia where it ends at sunset in western Mongolia.
For lucky observers in Egypt, Turkey, Russia, Brazil, Mongolia, Libya,
Togo, Nigeria and Chad, the Moon will completely obscure the Sun and
cause almost total darkness for a few minutes. This is the total solar
eclipse and such an event only happens every few years.
In addition, many countries in Europe will enjoy the spectacle of a
partial eclipse. This partial eclipse will be seen within the much
broader path of the Moon's penumbral shadow, which includes the northern
two thirds of Africa, Europe, and central Asia.
A solar eclipse occurs when the Moon comes between the Sun and the
observer. This happens when the shadow cone of the Moon intersects the
surface of Earth, and is observable by anyone within this shadow zone.
You need to take some precautions if you want to enjoy watching the
eclipse. Looking directly at the Sun can be very dangerous!
Looking directly at the photosphere of the Sun (the bright disk of the
Sun itself), even for just a few seconds, can cause permanent damage to
the eye because of the intense visible and invisible radiation that the
photosphere emits. The retina of your eye has no sensitivity to pain,
and the damage may not appear for hours, so there is no warning that
injury is occurring.
SOHO and the eclipse
Any total solar eclipse is an exciting opportunity for unique
observations from the ground. Free from the overwhelming glare from the
Sun itself, the corona that surrounds it is usually the prime target for
So almost invariably during any eclipse, expeditions go out to whatever
sites seem favourable, to capture what may be a once-in-a-lifetime
observation of phenomena that are otherwise hidden by the brightness of
To make the most of the observations, however, some expeditions are
relying on additional data supplied from the ESA/NASA SOHO and other
spacecraft, either to determine the pointing of their instruments, for
context information to help interpret the data in a broader setting, or
Especially in demand are images from the EIT and LASCO instruments on
SOHO. EIT observes the storms in the Sun's atmosphere by ultraviolet
light, which is blocked by Earth's atmosphere.
LASCO is a visible-light coronagraph that keeps the Sun perpetually
eclipsed by masks in its telescopes. Viewing a huge volume of space,
LASCO can show how features seen close to the Sun, by ground observers
during the eclipse, relate to space weather further out.
* SOHO overview
* SOHO 10-year special
* What is an eclipse?
* The science of eclipses
* The eclipse in history
* Bad moon rising ...
* Relativity and the 1919 eclipse
* ESA/NASA SOHO homepage
* Watch eclipse with ESA
* Watch eclipse with ESA/NASA's SOHO
Eclipse of the Sun at solar maximum (Courtesy Wendy Carlos)
Do not look directly at the Sun without proper protection!
ESA Sun worshippers at ESTEC, Noordwijk, The Netherlands, use special
mylar sunglasses to view the Venus transit of the Sun in 2004.
Credits: ESA/R. Van Haarlem
A SOHO LASCO C2 image of the solar corona. LASCO (Large Angle
Spectrometric Coronagraph) is able to take images of the solar corona by
blocking the light coming directly from the Sun with an occulter disk,
creating an artificial eclipse within the instrument itself.
The position of the solar disk is indicated in the image by the white
circle. The most prominent feature of the corona are usually the coronal
streamers, those nearly radial bands that can be seen. Occasionally, a
coronal mass ejection can be see being expelled away from the Sun and
crossing the fields of view.
This C2 image shows the inner solar corona up to 8.4 million kilometres
away from the Sun on 20 June 2001.