Mercury is ending it’s second evening apparition of 2012. Over the next few days the planet will slide into the sunset heading for inferior conjunction on July 28th and a morning apparition beginning in the first days of August.
Category: Astronomy
Exploring the cosmos
Astrophoto Interference on Mauna Kea
Mauna Kea is simply a great place to shoot astrophotos from. Dark, clear skies with typically good seeing. Unlike some mainland locations there is a distinct lack of aircraft overhead. I am not sure how many shots I have had ruined by the bright anti-collision strobes crossing through the frame when shooting from locations in Arizona.
There are hazards to shooting photos here that do not commonly exist elsewhere. I was unpleasantly surprised when reviewing the take the next morning to find brilliant yellow lines through a hour and a half of exposures taken of the Cygnus region. The material is otherwise great, the makings of a nice shot, except for this one little issue. There are ways of suppressing artifacts like this when processing, but the beam is so bright I am not certain they will work all that well.
Worse, I checked the schedule, the offending laser is coming from Keck 2 AO, a system I work on.
The observatories have a system in place to deal with this issue. There are four operational lasers on the mountain, Keck 1 and Keck 2, Subaru and Gemini. Each optical observatory using a laser maintains a server that posts their laser location, status, and calculates the position of each beam in the sky. This can be queried by the other observatories to check if the beam crosses the field of view. A set of rules has been negotiated to determine who has right of way, usually who is on target first.
Obviously this computer system does not take into account my little telescope shooting photos from Hale Pohaku. If I had known I could have called Heather and asked her to shutter her laser, I was on target first. Being the kind soul she is, she would probably laugh with me.
Postcard from the Universe – Morning Conjuction
The Moon, Venus and Jupiter
The three brightest natural objects of our sky, after the Sun, will join to form a nice group tomorrow morning. The dawn of 14 July will see a thin crescent Moon and Venus only 11° apart. The bright Jupiter will be in between, only 6° from Venus. Jupiter will be shining brightly at better that -2 magnitude, Venus will be even brighter at over -4 magnitude. The pair will be a nice match for an 18% illuminated Moon.
The next morning, July 15th, will still see the trio quite close. The Moon will have moved east to a position just 4° north of Venus.
Private Foundations Fund New Astronomy Tool
W. M. Keck Observatory press release…
The W. M. Keck Observatory has been awarded two major grants to help build a $4 million laser system as the next leap forward in a technology which already enables ground-based telescopes to exceed the observational power of telescopes in space. The new laser, when installed on the current adaptive optics system on the Keck II telescope, will improve the performance of the system and advance future technology initiatives.
“Ever since Galileo, astronomers have been building bigger telescopes to collect more light to be able to observe more distant objects,” said Peter Wizinowich, who leads the adaptive optics developments at Keck Observatory. “In theory, the larger the telescope the more detail you can see. However, because of the blurring caused by Earth’s atmosphere, a 10-inch or a 10-meter telescope see about the same amount of detail.”
Continue reading “Private Foundations Fund New Astronomy Tool”
Postcard from the Universe – Galactic Center Grande
On request I am publishing a larger version of my galactic center shot. I really do need to re-shoot this with an Hα sensitive camera.
As usual, click on the image for the larger version…
Venus and Aldebaran
Tomorrow morning, July 8th, Venus will pass less than 1° from Aldebaran. The Eye of the Bull may be one of the brightest stars in the sky at 0.9 magnitude, but it is no match for Venus at -4.4 magnitude.
On the morning of the 8th the planet will be 59′ from the star, just an iota under 1°. On the morning of the 9th the distance will be slightly closer at 55′. The pair will rise about 03:18, to be well up in the sky before sunrise.
Postcard from the Summit – Weather Tower
Apehelion
Today the Earth is furthest from the Sun, a point called apehelion. We will be about 152,098,232km (94,509,459miles) from the Sun. Compare this to the 147,098,290km (91,402,639miles) we were at perihelion on Jan 4th, a difference of about 5,411,169km (3,362,344miles) occurs throughout one orbit.
It may seem odd that we are actually at the furthest for the middle of northern summer, you just have to remember that proximity to the Sun is not the cause of the seasons. The seasons are caused by the axial tilt of the Earth, creating short and long days throughout the year, with a resulting change in the angle and intensity of the sunlight.
| 2012 Solstices and Equinoxes | ||||
|---|---|---|---|---|
| UT | HST | |||
| Perihelion | Jan 5 | 03:59UT | Jan 4 | 17:59HST |
| Spring Equinox | Mar 20 | 05:14UT | Mar 19 | 19:14HST |
| Summer Solstice | Jun 20 | 23:09UT | Jun 20 | 13:09HST |
| Apehelion | Jul 4 | 23:59UT | Jul 4 | 13:59HST |
| Fall Equinox | Sep 22 | 14:49UT | Sep 22 | 04:49HST |
| Winter Solstice | Dec 21 | 11:12UT | Dec 21 | 01:12HST |
| Source: USNO Data Services Website and the NASA Sky Calendar | ||||
Employment at Keck – Infrastructure Technician-Electrician
W. M. Keck Observatory Position Announcement…
The W.M. Keck Observatory operates two of the world’s largest and most scientifically productive optical/infrared telescopes located on the summit of Mauna Kea on the Big Island of Hawaii. A highly capable and motivated staff operates, maintains and develops the complex telescope systems and infrastructure on the summit. We seek an Infrastructure Technician-Electrician to join this high-caliber team.
Commitment to WMKO’s core values, working well with others, and the ability to handle multiple tasks and priorities within a fast paced environment are all essential. For a full listing of duties and qualifications for this position, please go to: www.keckobservatory.org/about/employment