Wednesday, December 7, 2011

A Total Lunar Eclipse

On Saturday night, December 10th, the full moon will cross through the Earth's shadow.

The moon will rise in the east just as the sun is setting in the west at 4:35PM.  By the time the moon rises, it will already be fully eclipsed.  Usually a totally eclipsed moon appears as a pale, coppery red sphere, but this time the sky will not yet be dark enough, so the eclipse will be very difficult to see.

By 5PM, however, the total phase will be complete and the edge of the moon will begin to emerge from behind the Earth's shadow.  The sky will by then be dark enough so that the brightening sliver of the moon should be visible for those with an unobstructed view of the eastern sky.  During the next hour or so, the moon will continue to move from the shadow, growing from crescent to full.  By 6:15PM, the moon will have returned to its normal "full" self again.
Enjoy, as this is the last total lunar eclipse till 2014!
Detailed times:
Beginning of total eclipse 16:06
Moon rises in eclipse 16:31
Sunset : 16:35
End of total phase : 16:57
(end of twilight 17:02 )
End or partial phase 18:17

(All times are Israel Standard Time)

Wednesday, November 9, 2011

Great time to see planetary alignment

Venus is back. Mercury is up. Jupiter is at apposition. The Moon is full.

If you go out right now (or tomorrow at the same time) you can see Venus low in the west above where the Sun set abut half an hour ago. You can't miss bright Venus, which is often confused for a passing airplane. About 1 finger below, at the 7 O'clock position is much fainter Mercury, now at about its peak height for this appearance. Now, turn around and you'll see big Jupiter rising in the aast, nearly as bright as Venus, although it is about 5 times as far away. Right beside the king of planets you'll find the full Moon. (Tomorrow the moon will be lower, just rising at this hour.).

Now imagine what all this looks like from out in space. We have the Earth in the middle with Venus, Mercury and the Sun to one side, and the Moon and Jupiter on the other. All one one line as seen from above. A picture perfect alignment.

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Friday, October 28, 2011

New Moon and Venus tonight

Tonight will be the 1st visibility of the new moon in Israel. It will be visible from around 5pm till it sets at 6. If it will be clear, you can also get an early peek at Venus very low to the right of the moon. Venus has just returned to our night sky, and will be getting higher and easier to see each night.

The arrangement in bright twilight
Sky & Telescope

You may also be able to spot Mercury, but you will probably need binoculars. It is very low and 3 magnitudes dimmer than Venus.

The horizon will look similar to this sketch from Sky & Telescope except that the moon will be lower and to the right here in Israel.


Wednesday, September 28, 2011

New moon on Rosh Hashana (Thursday night)

Happy new year to you all.

Sorry for the late notice, but as we get ready for Rosh Hashana, it is time to get set to find the new moon. This year it works out nicely with the moon visible at the beginning of the second night of the holiday. See details below from the Israel new moon society

Also, there is a violent storm happening on the sun right now. It is so bi that you can see it on the face of the sun without a telescope. DO NOT LOOK AT THE SUN WITHOUT APPROVED SOLAR FILTER. (See my blog for  safe methods of solar viewing.)

The Moon is likely* to appear over the South-Western
horizon between 18:14 and 18:39 on Thursday 29th
September 2011, 1¼ spans left of the sunset and 1½ fists (at
arm's length) high. The Moon will be very easy to see until
it fades or sets between 19:21 and 19:40. Illum. 6.93
(7.19)% Lag 72 m.

The Moon at 18:14, 1¼
spans (30°) left of the
sunset, 1½ fists (15°) high

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Sunday, September 18, 2011

Goodby Summer Stars

Summer Triangle

Now that you are all back from summer vacation, lets pay attention to the stars once again! The autumn stars are rising in preparation for the equinox on the 23rd. Although we are sad to see summer go, it gets darker earlier so we can enjoy the stars longer!

After a nice show, Saturn has exited the sky in the west, but the king of planets, Jupiter, is now back in the east. Also by month end, our long lost friend, Venus will be back in the evening sky right after sunset.

To keep up with the sky, I recommend you check out the weekly Sky at a Glance feature at Sky & Telescope

For a nice printable map of this months sky get the Abrams Planetarium Sky Calendar


Sunday, August 28, 2011

Off the Beaten Track

Had a fun interview today on the Off the Beaten Track show of Off the Beaten Track internet radio.
We spoke about the upcoming new moon of Elul which will be visible (but tricky) this Tuesday night and other heavenly subjects.


Friday, June 10, 2011

Preview video for next weeks lunar eclipse

Here is a nice preview of what to expect next week courtesy of NASA Lunar Eclipse Essentials

Be ready Wed night June 15th:  
9:22 pm  - partial phase begins
10:22pm - total phase begins
00:02am - total phase ends
1:02am   - partial phase ends

Sunday, June 5, 2011

Next week the moon will disappear . . . and reappear!

Don't miss next week's total lunar eclipse!

ליקוי ירח מלא, צילום: NASA/JPL-Caltech

This exciting event will begin next Wednesday night, June 15,at 21:22.  The shadow, caused by the moon passing behind the earth so that the earth is between the sun and the moon, will grow across the face of the moon until the moon is completely covered at 22:22.  At that point, the moon will turn interesting shades of orange/red until 2 minutes after midnight, when the other side will begin to emerge from the shadow.  At 1:02, the moon will have fully re-emerged.

This will be one of the darkest lunar eclipses. See details here.

And for your Hebrew reading  friends: מתי מתרחש הליקוי?


Sunday, May 15, 2011

Play with the planets

Tonight I did a fun interview on Off the Beaten Track show on Israel Sports Radio
The topic was the current planetary alignment and Shmuel from the show pointed me to this neat flash orrery

Here is a screen shot showing the current alignment. The planets and orbits are not to scale in this program, but it is still cool to play with. See the interactive flash here

 If you want a more complete night sky simulator you can download Stellaruim free for your computer.

During the interview I was also asked about this really cool video of a comet hitting the sun a few days ago.

It turns out that these kind of comets are actually fairly common, but we don't always get such a good video!