Category: Sky Events

Sky events

Comet C/2011 L4 Pan-STARRS

Like so many other amateur astronomers, I am eagerly awaiting the appearance of Comet C/2011 L4 Pan-STARRS.

The comet was discovered in June of 2011, by the Pan-STARRS survey telescope atop Haleakala, Maui. The comet will pass closest to earth on March 5th, at a distance of 1.09 au. Perihelion, the comet’s closest approach to the Sun, occurs early on March 10th UT.

Comet 2011 L4 Perihelion
C/2011 L4 (PanSTARRS) positions in the sunset as it passes through perihelion, chart for march 10th
For northern hemisphere observers the comet is still quite low, just rising out of the Sun’s glare. Over the next week it will rise above the sunset, and will be 12° above the horizon at sunset on Saturday, March 9th.

Initial predictions were quite optimistic with this comet, indicating a possible -1 magnitude for the comet. Reality seems to be somewhat more restrained, with a peak somewhere between magnitude one and two being more likely. Reports indicate that the comet has brightened to about 2nd magnitude, bright enough to be easily seen without optical aid.

Even more convenient, the comet will be well placed for observation this coming weekend. With new moon occurring on March 11th, this will be the prime weekend for a telescope outing. Amateur astronomers everywhere are already planing for this weekend. Our local club is no exception, expect a good crowd of telescopes to be at the Mauna Kea VIS this weekend. Myself? I will probably setup at the Substation site, just across the road from the VIS. The site offers a much better western horizon, which is blocked from the VIS by a line of pu’u, old cinder cones.

I will be taking photo gear, looking to get a decent photo of the comet. Stay tuned to Darker View to see the results if I meet with any success.

The latest orbital elements from the MPC

Another interesting opportunity will come on March 12th, when a slim crescent Moon will join the comet in the sky. A 1.4 day old moon, about 2% illuminated will be about 4° north (to the right) of the comet.

Mercury at Maximum Elongation

Today Mercury reaches maximum elongation, the furthest point it will reach from the Sun in the sky and the highest it will be above the sunset for this evening apparition. The planet is easily visible as a bright, starlike object about 18° above the setting Sun as twilight begins. Over the next couple weeks Mercury will slide back into the sunset, heading for inferior conjunction on March 4th.

Continue reading “Mercury at Maximum Elongation”

Meteor Airbursts over Chelyabinsk

A good sized meteor has airburst over the city of Chelyabinsk, Russia. There are reports of injuries and damage, but how much is unclear right now. Give it a day and we will probably have a good idea of the scale of this event, and probably fragments of the meteor itself.

A lot of vehicles in Russia carry dashcams, and videos of the event are rapidly showing up on YouTube. It is quite spectacular, the bright fireball saturating the closer cameras.

I have seen meteoric airbursts, but nothing on this scale. It is impressive, and a bit scary to be reminded that this can happen. This even almost certainly has nothing to do with the close approach of asteroid 2012 DA14 tomorrow, but I am sure some people will make a connection. The conspiracy theorists will probably go further, perhaps much further, it should make amusing reading.

Update: A link to a collection of videos and photos of the damage here. Midway down is a vid from a warehouse security camera of a loading bay door blown inwards by the blast wave.

A dashcam video of a meteor airburst over Chelyabinsk
Warehouse loading bay door blown inwards by meteor blast wave

Mercury and Mars

Tonight and tomorrow the pair of planets, Mercury and Mars will be about 30′ apart, close enough to easily fit in the low power view of most small telescopes. The pair will be 13° above the sunset, setting about an hour after the Sun slides below the horizon.

After the 8th the pair will separate, with Mercury heading for maximum elongation on February 16th.

Mercury and Mars

For the next few evenings Mercury and Mars will pair in the sunset for a dance. Tonight the two are 3°13′ apart, with Mercury rising rapidly. Tomorrow the two will be only 2°17′ apart. On the 7th and 8th there will be about 30′ between the two. After the 8th the two will gradually draw apart. On the 10th the separation will be just over 2° with the addition of a 1.8% illuminated Moon just 7° lower and north of the pair.

The pair should be easy to spot. Mercury will be shining brightly at -1 magnitude with Mars at about 1.2 magnitude. A pair of binoculars might help spot the dimmer Mars.

Neptune is also in this dance, but at 8th magnitude it could be very difficult or impossible to spot, even with optical aid. On the 5th, with Mercury and Mars only 2&deg apart, Neptune will be right between the two.

Mars and Neptune

Tonight and tomorrow night Mars and Neptune will be under a degree apart. But, as the pair is quite low in the sky, this may not be observable. The planets will be 40′ apart tonight, a little closer tomorrow at only 27′ separation. The pair will be 14° above the horizon at sunset. Mars, shining a 1.2 magnitude should be relatively easy to spot. The 8th magnitude Neptune may be too dim to see, even with a telescope, against the bright glow of sunset.

On the evening of February 5th, Mercury will join in to create a trio, just 2° below Mars with Neptune between the two.