message posté le 29 août 2007 à 03h12

membre
montreal

Je marque ça sur mon calendrier de 2008!

En passant il y a une éclipse lunaire totale ce soir (28 aout) Toute une coïncidence que jai vu ça! Je ne me rapellais plus qu'est ce que c'était, je vais voir sur wikipédia, surprise! Ils annoncent une éclipse lunaire totale ce soir!

voici ce qu'ils disent sur le site de la NASA:

Citation

Total Lunar Eclipse of August 28
The second lunar eclipse of the year is another total eclipse. It is a deeper event since it is the first central total eclipse since 2000. The eclipse occurs at the ascending node of Luna's orbit in southern Aquarius. Since the Moon is 2.6 days shy of perigee, it will appear 8% larger (= 1.2 arc-minutes) than it was during March's eclipse. The Moon's trajectory takes it deep into the southern umbral shadow, resulting in a total eclipse that lasts 90 minutes. At mid-totality the Moon's centre passes just 12.8 arc-minutes south of the shadow axis. This places the Moon's northern limb only 3.4 arc-minutes north of the axis while the southern limb is 15.4 arc-minutes from the umbra's southern edge.

Since different parts of the Moon will probe radically different portions of Earth's umbral shadow, a large variation in shadow brightness can be expected. As a consequence of this geometry, the southern half of the totally eclipsed Moon will appear considerably brighter than the northern half. Observers are encouraged to estimate the Danjon value at mid-totality (see Danjon Scale of Lunar Eclipse Brightness).

The penumbral phase of August's eclipse begins at about 07:54 UT, but most observers will not be able to visually detect the shadow until about 08:30 UT. A timetable for the major phases of the eclipse is listed below.

Penumbral Eclipse Begins: 07:53:39 UT
Partial Eclipse Begins: 08:51:16 UT
Total Eclipse Begins: 09:52:22 UT
Greatest Eclipse: 10:37:22 UT
Total Eclipse Ends: 11:22:24 UT
Partial Eclipse Ends: 12:23:30 UT
Penumbral Eclipse Ends: 13:21:01 UT

The Moon's path through Earth's shadows as well as a map illustrating worldwide visibility of the event are shown in Figure 3.

At the instant of mid-totality (10:37 UT) the Moon will stand near the zenith for observers in French Polynesia. At that time, the umbral eclipse magnitude will be 1.4760.

All of North America will witness some portion of the eclipse, but western observers are favored. The early penumbral or umbral phases will be in progress at moonset for observers in Maritime Canada. From the eastern USA, the Great Lakes region and Ontario, the Moon sets in total eclipse. Only observers to the west of the Rockies (including Alaska) will be treated to the entire event. All phases of the eclipse are also visible from islands of the Pacific Ocean, New Zealand and eastern Australia. Various stages of the eclipse are in progress at moonrise for eastern Asia. No eclipse is visible from Europe, Africa and western Asia.

Table 3 lists predicted umbral immersion and emersion times for 20 well-defined lunar craters. The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see Crater Timings During Lunar Eclipses).