· By Shinpei Tsubogami
How to See the Southern Cross on Ishigaki Island
The whole Southern Cross is visible from Ishigaki from January to May — early evening in April and May, before dawn in January and February. Its lowest star only reaches about 2.6°, so you need an open southern horizon.
The Southern Cross (Crux) is the best-known constellation of the southern sky. In Japan it barely clears the southern horizon, so you can see all four stars only from the far south, such as Okinawa. Ishigaki is one of those places.
From Ishigaki (24.3°N), Acrux, the lowest star of the cross, rises at most about 2.6° above the horizon, and Gacrux, the top star, about 8.6°. You need an open view of the southern sea and a night without clouds or haze near the horizon.
When the Southern Cross is up, month by month
| Month | Southern Cross |
|---|---|
| Jan | 4:05–6:10 |
| Feb | 2:05–4:50 |
| Mar | 0:15–3:00 |
| Apr | 22:10–1:00 |
| May | 20:45–23:00 |
| Jun | Not visible |
| Jul | Not visible |
| Aug | Not visible |
| Sep | Not visible |
| Oct | Not visible |
| Nov | Not visible |
| Dec | Not visible |
Hours when all four stars are above the horizon in a dark sky. Calculated for Ishigaki on the 15th of each month, rounded to 5 minutes. From June to December it does not rise during dark hours.
Tips
- April and May are the richest months: the Southern Cross in the early evening and the Milky Way later the same night.
- Clouds and haze often sit near the horizon, so some nights it will not show.
- Two bright stars of Centaurus (Alpha and Beta) line up to its left and make it easy to find.
On the star photo tour, when it is up, we point out the Southern Cross with a laser pointer.