香港天文論壇

Here is the preliminary results (time in UTC):
Start of observation: 16:30
star & asteroid merged : 17:36:30
star dimmed: 17:40:56.183 (start of occulted)
star brightened : 17:41:12.733 (end of occultation)

star and asteroid separated: 17:44:50


pts

WC Yue's prediction is good to the second.
We visually observed the dimming at 17:41:00 UTC!

pts

Hi, Since I have more than 2 hours before the asteroid occultation, I have just captured some images of this dwarf nova. The StellaCam3's FOV is too small and cannot capture both comparison stars in one frame. Instead I have to use my Imperz 4M15. I'll try to post some images tomorrow, as I am now b...

PTS 寫:Just a reminder.

pts

The sky is very clear. I am able to capture the 14.4 mag star with a 4 second exposure.
The asteroid is plainly visible and is moving towards the star.

pts

Just a reminder.

pts

Hi,
I've prepared finder charts for BW Scl.
All charts are 15 x 15 arcmin.
The bright star to the north (above) is of mag. 10.7 while the one below (south) is of mag 12.

pts

AAVSO Special Notice #261 Outburst of the UGWZ candidate BW Scl October 21, 2011 The short period cataclysmic variable BW Scl appears to be in outburst. The object was detected in outburst at m(vis)=9.6 by M. Linnolt on 2011 October 21.3146 (JD 2455855.8146), and confirmed by A. Plummer at m(vis)=9....

Here is the timings (all UTC time): Observation started : 16:58 Star & asteroid merged: 17:55 star disappeared : 18:03:19.430 Star re-appeared: 18:03:24.755 re-emerging of asteroid: ~18:10 Star & asteroid separated: 18:12:55 Remarks: Before merging of asteroid and star, recording was done at setting...

Here is the timings (all UTC time): Observation started : 16:58 Star & asteroid merged: 17:55 star disappeared : 18:03:19.430 Star re-appeared: 18:03:24.755 re-emerging of asteroid: ~18:10 Star & asteroid separated: 18:12:55 Remarks: Before merging of asteroid and star, recording was done at setting...

Hi,
The sky was very fine last night.pts

It seems favorable tonight.

pts

AAVSO Special Notice #258 Request for monitoring of SS Cygni in support of European VLBI radio observations October 13, 2011 As mentioned in AAVSO Alert Notice 445 on August 19, 2011, Dr. James Miller-Jones (International Centre for Radio Astronomy Research, Curtin University, Perth, Western Austral...

skynam 寫:把力施加於物件上,除了有反作用力之外,力還能否轉彎傳導,如90度角轉彎,如果有可能有方法,會否可以像飛碟般懸浮起來?

1. The worm gear system is an example. The axle of the worm is usually at right angle to the axle of the gear.

2. The pulley is another example

3. ...
4 ....

Too many examples

wtyu21 寫:今晚睇完新聞，聽說佔領華爾街的抗議人士講，年薪低於四萬美金，要養車、要供樓、要養狗～咁窮，活在貧窮線之下，叫佢地點過日子～

三十二萬一年，香港白領要好高級先至有呢個價位，美國人真係～

This is when relativity can be applied to daily life!

pts

It seems the chance is slim.

pts