The project now has 28 fixed points. The newest, TP-02, stands at the edge of the Balio gardens on the summit of Erice, a few kilometres from TP-01 on the Trapani seafront and about 750 m above it.
Why here
It gives us a rare pair: two points close enough to share the same weather, separated mostly by height. Much of the haze that scatters Trapani’s light sits below the summit, and we want to know how much that matters over a full year.
First readings
| Session | Point | Median |
|---|---|---|
| 15 May | TP-02 Erice | 20.12 |
| 17 May | TP-02 Erice | 20.08 |
| May, 3 sessions | TP-01 Trapani seafront | 18.43 |
Taken together the two Erice sessions give 20.10. That is 1.67 above the seafront, so the sky at the summit is about 4.7 times darker. It is a small sample, and we will revisit it at the end of the season.
The cloud problem
Anyone who knows Erice knows what comes next. Moist air from the sea condenses on the summit and the town disappears into a cloud that locals call the kiss of Venus. Of our first four attempts, two ended with the meter still in its bag. We expect to lose about half of our nights up there.
On the plus side, there is no lamp within 40 m of the point, and the town has been very kind about people standing in the dark holding a box above their heads.