Will Comet C/2011 W3 Lovejoy be visible in the daytime? This is the morning to find out. Look about 2° below the rising Sun once it is well up in the clear sky for a small white object. Two degrees is four times the Sun’s width in the sky.
C2006/P1 McNaught photographed five degrees from the Sun, stack of three imagesIf the comet is not visible to the eye, it should be spectacularly visible in the imagery sent back by one of our solar monitoring satellites. Check out the SOHO page for the latest imagery. The comet should have entered the field of view of the LASCO C3 instrument early on Dec 14th (late on the 13th HST) and well in by the time this posts. If the comet does not survive perihelion passage, this is one of the best views of the event.
I have seen one other daytime comet in my life, C2006/P1 McNaught back in January of 2007. That time the comet was about 5° from the Sun, over twice as far away from the glare. The photo at the right should give an idea of what to look for today. Remember to shield your eyes from the Sun’s glare by positioning yourself to put the Sun behind some object like a wall or streetlight. There is no guarantee that Lovejoy will be at all visible, but it is worth taking a look this morning.
The annual Geminid meteor shower has become one of the most reliable annual meteor showers. First observed over 150 years ago this is a interesting meteor shower. The parent body for the Geminids is not a comet, but rather the asteroid 3200 Phaethon. It is somewhat of a mystery how this mostly rocky body gives rise to the debris stream needed to generate a meteor shower.
The evening of Dec 14th into the morning of Dec 15th is favored, starting around 8pm as Gemini rises in the east.
While the 2011 Geminids are expected to just as numerous as usual, viewing will be hampered by a bright Moon in the sky. Certainly the brighter fireballs will be easily visible, but the dim meteors will be lost to the moonlight. If you do wish to try your luck, view between midnight and dawn on the night of the 14th and into the morning of December 15th. It may be possible to see some meteors after the radiant rises, about 8pm, and before moonrise around 10pm on the evening of the 14th.
Plans for a summit run and some lunar eclipse photography. A midnight alarm clock and departure for the summit was the strategy. I planned to shoot time lapse of the eclipse setting over the Keck telescopes. But the best laid plans sometimes hit a snag…
I had noticed some minor power loss and roughness in the engine heading into work. Some condensation in the system? Perhaps just some bad gas? It was on the way home that the trouble became truly clear. A rhythmic stutter accompanied by a more severe power loss. As I limped home listening to the engine I realized that at least one cylinder of the six was not firing. A faint smell of gas when I got out of the vehicle just seemed to confirm the hypothesis.
That evening I spent a bit poking at the engine, inspecting for a loose connection or some other easy cause. I removed and cleaned the mass air sensor, a known trouble spot. Checked the air intake and ignition system. Removed battery power to allow the electronic engine controls a full reset to default settings. Still, when I started it up there was that rhythmic stutter.
Total lunar eclipse of 28 Aug 2007, photo is a 8sec exposure with a Canon 20Da on a 90mm f/12 APOI was not going eclipse chasing this night. No way was a partially crippled vehicle going to make it to the summit of a 14,000ft mountain.
Instead I simply set the alarm clock for a bit before totality and watched the eclipse from my front lanai. I made no attempt at photography, I do have quite a few decent eclipse photos. Instead I simply watched as the Moon ghosted through a thin layer of clouds. It was quite pretty, a bright Orion and Gemini were visible through an opening for a while. Much of mid totality was lost to the clouds, but it opened up again at the end allowing a nice view of the first touch of direct sunlight on the Moon.
As for the vehicle? I still was not certain what was the issue. This could be the result of something truly serious considering the engine has well over 180,000 miles on it. Plans for a replacement vehicle are under consideration, but I love this old truck. The first new vehicle I had ever owned, a veteran of hot dusty Arizona mining roads, of icy mountain passes, of rocky Hawaiian coastlines carrying scuba gear in the back. How many times has this vehicle waited through the night, telescope setup beside it, while I explored the sky from some remote and dark campsite? A trusted steed that has carried me to so many great places and always gotten me home.
The maintenance manual has a list of a dozen things that can cause misfires. May as well start with the easy (and cheap) stuff. I drove Deb’s car into Waimea to run a few errands and pick up a set of ignition cables and spark plugs.
A damaged spark plug cable shows why.It was the first cable I removed the revealed the trouble, a bad break in the cable where it had rubbed against a mounting bracket for the fuel line. Arced and blackened it was clear that my hunch was correct. A sense of relief, perhaps it was something this simple. I won’t know until I finish the job of replacing all six cables and plugs.
That would be almost two hours later, two hours of cursing the engine designers who would obviously not ever have to replace the plugs on this engine. Who puts a hard fuel line right in line with the spark plugs? I go back to the toolbox for the 3/8″ universal joint and spend a few minutes figuring out what combination of extensions will get me through which gap in the hoses and lines. Really? Is cylinder three’s plug under there? I will have to do it entirely by feel.
Finally! All plugs in place, cables neatly routed around the block, tools picked up from around the engine compartment, I have a chance to turn her over. A quick crank and she starts, idling with a smooth purr that is simply music to my ears. My old friend will be with me for a little longer.
This was the last total lunar eclipse for the next three years. I did watch it, remembering other total lunar eclipses across the years. An eclipse seen from among a stand of saguaro cacti in the Arizona desert, another eclipse watched from the Mauna Kea VIS just a couple years ago. A copper moon high over the broken walls and ruins of a 12th century priory. This eclipse will mark yet another memory, to be recalled when I again sit under a blood red Moon in the middle of the night.
The rumor is running around the various astronomy sites and listservers that Comet C/2011 W3 Lovejoy might be daytime visible. Will it be? That is a very qualified maybe.
C2006/P1 McNaught photographed five degrees from the Sun, stack of three imagesThis sun-grazer comet was discovered just a few days ago, on November 27th, by Australian amateur astronomer Terry Lovejoy. The comet is a member of the Kreutz comet family, and like other members of the family it will approach the Sun quite closely, about 548,000 miles (882,000 km) from the Sun. Of course those distances are solar centric distances. Taking the radius of the Sun into account means that the comet will be a mere 115,000 miles (186,000 km) above the photosphere, hot indeed!
It becomes a valid question to ask if comet Lovejoy will even survive perihelion transit.
Passing that close to the Sun will mean that the volatile elements of the comet will be streaming off the comet at a fantastic rate, enough to dramatically brighten the comet. Below you will find the ephemeris for perihelion on Dec 16th (Dec 15th HST) from the Minor Planet Center. As you can note, the predicted magnitude is -8! This is bright enough to be seen in broad daylight. Thus the possibility of a daytime comet.
The catch is that the comet will be quite close to the Sun. Within 2° as the Sun and comet rise on the morning of the 15th here in Hawai’i. For observers in the islands the best chance to look is on the morning of the 15th, as perihelion will occur in the afternoon as the comet passed behind the Sun from our point of view.
Will it be visible? Maybe. It depends on the accuracy of the magnitude estimates, which are uncertain to say the least. It could be substantially dimmer, or even substantially brighter than forecast under such conditions. The proximity to the Sun also complicates the issue. It is worth a look, seeing a daytime comet is highly unusual.
If you do look please take a few simple precautions… Do NOT use any sort of optical aid this close to the Sun, the risk of permanent eye damage is too great. If it is bright enough the comet should be a naked eye object. It will greatly help to position yourself to put the Sun just behind some obstruction. A building, a streetlight, anything to block the Sun’s glare and aid in picking out the comet. On the morning of the 15th the comet will rise 2° behind the Sun, thus 2° lower in the sky.
It was a beautiful evening as I drove home from work. The clear air allowing appreciation of all five volcanoes that loom over South Kohala. Indeed, the horizon was completely clear, the island of Kahoʻolwe visible over 60 miles away.
As I drove I noted the Sun beginning to settle into the distant horizon. At the wheel I couldn’t look long enough to be certain, but I thought I saw an Etruscan vase effect as the solar disk made first contact with the horizon. Curiosity peaked, I pulled over to properly watch the end of sunset. A pleasant surprise rewarded my view, a decent green flash was apparent as the last glimmer vanished.
Better yet, the camera caught the effect as well. Of the dozens of sunsets I have stopped and watched, this was the best green flash seen yet from such a high elevation. Still, it was modest compared to a couple flashes I have seen from sea level. I can only wonder how good this evening’s flash was as seen from the shoreline, 2,000 feet below.
A modest green flash as seen from the Mamalahoa Highway outside Waimea, 1 Dec 2011
For meteor watchers there is probably no more anticipated show that the annual Leonid Meteor Shower. The Leonids are renowned for reliable showings featuring bright fireballs.
The reputation is not without reason, Leonid events over the last decades have produced spectacular showers. The 2001 Leonids have become legendary, for a few brief hours on the morning of November 17th the shower became a true meteor storm, with rates of more than one thousand meteors an hour visible across the western United States and the Pacific. The sky was constantly peppered with streaks, many dim, but some very bright, every few minutes a fireball would be brilliant enough to light up the landscape. Other observers will mention that the 1998 Leonids produced a impressive number of bright fireballs, making that year particularly memorable.
1833 Leonids, the engraving is by Adolf Vollmy based upon an original painting by the Swiss artist Karl Jauslin, that is in turn based on a first-person account of the 1833 storm by a minister, Joseph Harvey Waggoner on his way from Florida to New Orleans.Nor is the 2001 event unprecedented. This has happened in the past, with Leonid meteor storms occurring several times in the last couple centuries. In 1833 a massive shower woke residents across the eastern United States with a fury that had many thinking that Judgment Day was upon them.
The Leonid meteor storms incited terror and religious revelation, but also stimulated the study of meteor science. It is from studies of these storms that astronomers began to realize that meteor showers were natural, and predicatable phenomena. This led to the realization that the annual meteor showers were associated with comets with orbits that cross the orbit of the Earth.
Just how impressive a show depends on a set of complex factors, meteor prediction is not an exact science, but astronomers are getting steadily better at these predictions. The meteoroids are found in clouds of debris left behind by a comet. In the case of the Leonids this is comet Temple-Tuttle, which has an orbital period of 33 years. All along the orbit of the comet there is a cloud of debris, small bits of dust and sand sized grains of rock-like material. Prediction is a matter of figuring out how this material will move about under the influences of gravity from the various planets and other factors like the pressure of the solar wind and even sunlight.
Unfortunately for meteor watchers, the 2011 Leonid shower is expected to be fairly weak, with ZHR rates around 20. There are some predicted peaks, due to specific regions of debris left behind by the comet several centuries ago, but the average meteor size is predicted to be quite small, leading to to faint meteors. This is further complicated by a bright waning gibbous Moon present during the shower peak. This is probably not a good year for Leonid observing.
Waimea is a place of rainbows. So common are they here it is a rare day that goes by without at least one rainbow.
But what does a rainbow look like at sunset? When the Sun’s light is reddened by passage through so much air and haze. The bow will begin to lose all color except for red, this creates a red bow…
A snow covered Mauna Kea at sunset as seen from Wiamea, with a bit of a red sunset bow above the western slope
I am waiting for the Moon to leave the evening sky before shooting the comet again. In the meantime I am processing more of the material obtained earlier in the month. In this case a photo of Comet 103P/Hartley 2 taken October 6th with Keck 2 and DEIMOS. The image marks the first time I have attempted to take and process an image with a 10m telescope. Just a wee bit larger than the 76mm refractor I usually use to take astrophotos!
The image is notable for its complete lack of any interesting structure. There are no jets, shells or other inner coma detail visible. The tail is simply a general brightening to the southwest (lower right in this image).
The comet is moving very quickly across the sky, even more so with the high magnification lent by a large telescope. Even short exposures turn the stars into long streaks. In this case multicolor streaks as the camera cycles through the filters needed for a color image.
Comet 103P Hartley 2 with Keck2 and DEIMOS 6Oct2010 @ 7:27UT, 3x60s, 3x60s and 3x120s with standard BVR astrometric filters, credit: Cooper/Wirth/W.M. Keck Observatory
A lunar halo may be quite pretty, but along with pretty sunsets, it indicates lousy sky conditions for astronomy.
In this case a high layer of thin cirrus, consisting of small ice crystals, cover the sky. The crystal shape is just right to bend the light at a specific angle, creating a halo 22° from the light source. A faint hint of color can be seen at the inner edge of the halo.
Thanks to all of those folks who posted comments about meteor fireballs. As I mentioned, these sort of events are not all that uncommon, and occur regularly across the globe. What is unusual is good photos of the event. This did happen this week, a photographer had a good camera at the ready when a similar fireball came in over Groningen, Netherlands on October 13th. Great photos of an event much like the one we saw last week over Hualālai. Check out his page for the full set of photos including the final breakup, the website is in Dutch, but a Google translation will let you follow the description.
