一九九八年三月五日的日暈
以下日暈的照片拍攝於一九九八年三月五日約下午二時十五分。當時天晴，一萬米上空有卷層雲。
常見的暈是一個視度半徑為二十二度的光環圍繞太陽或月亮，環內的亮度比環外的弱。當環的色澤很暗淡時，便只能看到白色的光圈；若很強時，便會看到內紅外黃的光環。
暈是冰晶把光折射而形成的，出現時天空一般會被卷層雲或厚的卷雲所覆蓋。
在香港，暈並非不常見，平均每年約有三天觀察到暈的現象。
以下為二十多年來天文台觀察到日暈的日數：
| 年 |
一月 |
二月 |
三月 |
四月 |
五月 |
六月 |
七月 |
八月 |
九月 |
十月 |
十一月 |
十二月 |
總數 |
| 1976 |
|
|
|
1 |
|
|
|
|
|
|
|
|
1 |
| 1977 |
|
|
|
|
1 |
|
|
2 |
|
|
|
|
3 |
| 1978 |
|
|
|
2 |
1 |
|
|
|
|
|
|
|
3 |
| 1979 |
|
|
|
|
|
|
|
|
|
|
|
|
0 |
| 1980 |
|
|
|
1 |
|
|
1 |
|
|
|
|
|
2 |
| 1981 |
|
|
|
|
2 |
|
1 |
|
|
|
|
|
3 |
| 1982 |
|
|
|
1 |
|
|
|
|
|
|
|
|
1 |
| 1983 |
1 |
|
|
|
|
|
2 |
|
1 |
|
|
|
4 |
| 1984 |
|
|
|
1 |
1 |
|
3 |
1 |
1 |
|
|
|
7 |
| 1985 |
|
|
|
|
1 |
|
|
2 |
|
|
|
|
3 |
| 1986 |
|
|
|
2 |
3 |
|
|
|
1 |
|
1 |
|
7 |
| 1987 |
|
|
|
|
|
1 |
|
|
|
|
|
|
1 |
| 1988 |
|
|
|
|
|
|
1 |
|
|
|
|
|
1 |
| 1989 |
|
|
1 |
1 |
|
1 |
|
1 |
|
1 |
|
|
5 |
| 1990 |
|
|
1 |
1 |
3 |
|
1 |
|
1 |
|
|
|
7 |
| 1991 |
|
|
|
|
|
2 |
|
2 |
|
|
|
|
4 |
| 1992 |
|
|
|
|
1 |
|
|
|
|
|
|
|
1 |
| 1993 |
|
|
|
|
2 |
|
|
|
|
|
|
|
2 |
| 1994 |
|
|
|
|
1 |
|
|
|
1 |
|
|
|
2 |
| 1995 |
|
|
|
2 |
2 |
|
|
1 |
|
|
|
|
5 |
| 1996 |
|
|
|
1 |
|
|
|
|
|
|
|
|
1 |
| 1997 |
|
|
|
1 |
|
|
|
1 |
|
|
|
|
2 |
| 1998 |
|
|
1 |
4 |
2 |
|
3 |
|
|
|
|
|
10 |
| 1999 |
|
|
|
|
|
1 |
|
1 |
|
|
1 |
|
3 |
| 2000 |
|
|
|
|
|
|
1 |
|
|
|
|
|
1 |
| 2001 |
|
|
|
|
|
1 |
|
1 |
|
|
|
|
2 |
| 2002 |
|
|
|
|
1 |
2 |
1 |
|
|
|
|
|
4 |
| 2003 |
|
|
|
|
|
1 |
|
|
|
|
|
|
1 |
