Postcard from the Universe – Venus Transit

Transit is over, an exhausting and exhilarating day! I am headed to bed, but still totally jazzed with the experience. Keeping the webcast going for seven hours was a huge effort. Given the comments from our viewers it was worth it. I will have to more fully write up the experience for a later post.

The best visual for the day was the few minutes just before second contact… A beautiful, razor thin arc of light coming through the Venusian atmosphere, connecting the two horns of the occluded Sun. It was delicate and sublime, one of the most memorable sights I have ever seen through a telescope. With the excellent seeing of Mauna Kea, and the wonderful optics of my TV-76 telescope, the sight was clear and steady. I have yet to find a photograph that captures what I saw through the eyepiece.

I will post a quickly processed version of one of the frames from the second camera…

Venus Transit Second Contact
Transit of Venus 2012, second contact at 12:27pm

Transit of Venus is Today

Transit of Venus
The June 2004 Transit of Venus, image credit Jan Herold
The gear is tested, packed and ready. All of the arrangements have been made. It is time for the 2012 Transit of Venus!

We will be webcasting the transit live from the Keck telescopes at the summit of Mauna Kea. Tune in for images of the transit, and a lot of information about the transit. Larry O’Hanlon and I will be talking about the transit, the science, the history, and just generally enjoying the experience. You are invited to join us. Expect the broadcast to start about 11:45HST, or about 25 minutes before first contact.

Want to see for yourself? There are multiple locations around the island where you will find solar telescopes and volunteer guides to answer your questions about this event. Not on the Big Island? Check you local paper or look up your local astronomy club to find public events. Science museums, colleges, astronomy clubs and other astronomy organizations are organizing public events wherever the transit can be seen.

Location Name External Sun
Ingress Alt

h m s °
Internal Sun
Ingress Alt

h m s °
Greatest Sun
Transit Alt

h m s °
Internal Sun
Egress Alt

h m s °
External Sun
Egress Alt

h m s °
Anchorage, AK 14:06:30 51 14:24:04 51 17:26:53 38 20:30:46 16 20:48:32 14
Honolulu, HI 12:10:07 85 12:27:46 89 15:26:20 49 18:26:38 9 18:44:38 5
Kona, HI 12:10:09 86 12:27:48 87 15:26:16 47 18:26:33 7 18:44:33 3
Los Angeles, CA 15:06:26 58 15:24:02 55 18:25:33 18 — – — –
Phoenix, AZ 15:06:03 54 15:23:40 50 18:25:32 13 — – — –
Portland, OR 15:06:05 57 15:23:40 54 18:25:53 23 — – — –
San Francisco, CA 15:06:29 61 15:24:04 57 18:25:39 22 — – — –
Seattle, WA 15:05:58 56 15:23:32 53 18:25:57 23 — – — –

All times local. The data is taken from Fred Espenak’s NASA Eclipse Website. I extracted the cities that are of most interest to my Hawaiian readers. For the full list of US cities you can go here.

Please exercise caution when viewing the Sun! Use appropriate eye protection or indirect observing techniques to project an image of the Sun. The link at the start of this paragraph leads to a great discussion on viewing the Sun safely. As always the single best source on the web (or anywhere) for eclipse and transit information is Fred Espenak’s eclipse website at NASA. Stop by whenever you have a question on upcoming events as well as viewing and photography tips.

Full Moon

Full Moon
Full Moon taken 27Aug2007, 90mm f/12 APO and Canon 20Da
Full Moon will occur today at 01:11HST.

A partial lunar eclipse will be visible from the west coast of North America to the east coast of Asia. At maximum about a third of the moon will have entered the Earth’s umbra, the inner shadow. Viewers in Hawai’i will be able to observe the entire event.

Continue reading “Full Moon”

Venus Transit Reminder

This is your last chance this lifetime to witness a Venus transit! On June 5th the Earth, Venus and the Sun will line up correctly so that earthbound observers will see Venus cross the disk of the Sun.

Mercury Transit
Mercury transiting the face of the Sun, 6 Nov 2006
Venus transits are relatively rare events, that occur in pairs1, with the paired events separated by eight years. Each pair is separated from the next pair in a predictable pattern, alternating 105.5 or 120.5 year gaps. The first transit of the current pair was in June 2004, with the 2012 event completing the pair. The next pair of events will begin in December 2117. Given the century long separation between events Venus transits have only occurred seven times since the invention of the telescope (1631, 1639, 1761, 1769, 1874, 1882 and 2004)2.

To witness this event you only need to be on the daylight side of our planet when it occurs. The 2012 event favors the Pacific, Australia, Japan and eastern Asia.

For Hawai’i the event will begin at about 12:10pm with the Sun high in the sky, mid-point will be about 3:26pm and will end about 6:44pm, just before sunset. These times are only approximate, exact times will depend on the observer’s location and can vary by several minutes across the islands.

As always the single best source on the web (or anywhere) for eclipse and transit information is Fred Espenak’s eclipse website at NASA. Stop by whenever you have a question on upcoming events as well as viewing and photography tips.

Keck Observatory will be making an extra effort for this transit as Mauna Kea is perfectly positioned to observe the event. We will be webcasting the transit from a small telescope located at the summit. The webcast can be seen on your computer, or come over to our headquaters in Waimea to see the webcast and a live view in a solar telescope if the weather cooperates. there will be extra staff on hand to answer your questions.

Stay tuned to DarkerView for further details as the transit draws near.

1) Transit of Venus, Wikipedia Article, retrieved 8 Feb 2009

2) 2004 and 2012 Transits of Venus, Fred Espenak, NASA/GSFC, NASA Eclipse Website, retrieved 8 Feb 2009

The Moon and Saturn

Saturn, the Moon and Spica form a trio high in the eastern sky at sunset tonight. The three will be within 7° of each other. The Moon will be just short of full, over 85% illuminated. Saturn will be shining at 0.4 magnitude while Spica is very close to 1.0 magnitude. Look for the planet Mars 38° west of Saturn and a bit brighter.

Venus Exits the Evening Sky

Over the next week Venus will be lost to the Sun’s glare. It is currently about 15° east of the Sun, but getting closer quite quickly now and becoming tough to spot in the sunset. The planet will pass through inferior conjunction on June 5th. The planet will appear in the dawn sky around mid June. When it does appear, it will again be in the company of Jupiter which passed through superior conjunction on May 5th. The two will again dance with each other and the Moon in mid to late June.

Of course, this upcoming inferior conjunction is just a bit special as Venus will pass directly in front creating the Venus Transit.

Even when low in the sunset, Venus is worth picking up in a telescope. As the planet approaches inferior conjunction it shows an ever more crescent appearance to our earthbound vantage point. During the last days of visibility it will be a razor thin crescent, worth the effort to look.

A Thin Moon and Venus

A very thin crescent Moon will join Venus low in the evening sky tonight. The Moon will be a mere 4.3% illuminated. Both will be about 20% above the setting Sun and about 6%deg; apart. As Venus approaches inferior conjunction and transit, it too will be a thin crescent, about 6.5% illuminated. You will need a telescope to see the phase of Venus, but the beautiful pairing can be appreciated with the eye alone.