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Comet Lovejoy

Comet Lovejoy

On the night of November 27th 2011 amateur astronomer and comet hunter Terry Lovejoy from Australia discovered something that he marked as “probable reflection” with his telescope. He checked back and it wasn’t a reflection at all, it was a comet. This comet named after his discoverer C/2011 W3 Lovejoy  belongs to what is known as the “Kreutz Sungrazers” family, comets with orbits bringing them really close to the sun, the theory is that these comets are fragments of a larger comet that was fragmented thousands of years ago.

Comet Lovejoy started then a journey of amazing highlights for the astronomical community. It’s the first comet of the Kreutz group to be discovered from the ground in 30 years, usually they are discovered using NASA’s solar telescopes such as SOHO or STEREO. After initial calculations the comet body was estimated to be as big as a football field, not enough to survive a close approach to the Sun. Comet Lovejoy was doomed.

Lovejoy Approaching the Sun

Lovejoy Approaching the Sun

While approaching the Sun Lovejoy brightened to magnitude -4, that’s as bright as planet Venus making it the third brightest object in the sky after the Sun and the Moon. It wasn’t visible to the naked eye because the comet was too close to the Sun, lost in the glare. This was supposed to be all, after perihelion the little comet would be destroyed into tiny fragments never to be seen again.

But comets are like a box of chocolate, you never know what you are gonna get. The astronomy world was amazed when the comet emerged from behind the Sun.

It's Alive!

It's Alive!

The comet emerged from behind the Sun and looked smaller and had lost its tail. It was a miracle for the little comet to have survived perihelion but that was only a small thing compared to what was coming. The comet re-formed it’s tail and brightened and now astronomers started to discuss the possibility of the comet being visible to the naked eye.

Due to its orbit Lovejoy is only visible to observers in the south hemisphere it started very close to the sun so astronomers and photographers had to hunt for it a few minutes before dawn, as soon as it cleared some degrees away from the Sun the show started.

Lovejoy at the Milky Way

Lovejoy at the Milky Way

The comet became visible to the naked eye before dawn, it was easy to see on December 23rd, I went to a rural location and at around 3am the tail of the comet rose from behind the trees at the horizon, it was a fantastic sight. It quickly brightened and its two tails were easy to spot with the naked eye and magnificent in photos.

The Two Tails of Comet Lovejoy

The Two Tails of Comet Lovejoy

The main tail curves above the horizon and is made of dust, the secondary tail is made of ionized gas and rises straight from the horizon. As said before both tails were easy to see with the naked eye.

As photos started to come from Australia, South Africa and Argentina the comet became bigger and brighter, people compared it with comet McNaught from 2007 and with Ikeya-Seki from 1965, the brightest comet in the history of mankind and also a member of the Kreutz family. Lovejoy wasn’t that bright, you had to go to rural areas to see it but it was really big with its tail extending for more than 20 degrees.

The Great Comet of 2011

The Great Comet of 2011

There is no formal definition of “great comet” but in some places they say that a comet needs to be bigger than 15 degrees and visible to the naked eye. If we take that definition then Lovejoy is without a doubt the great comet of 2011. It’s huge and bright enough to be an easy naked eye object from rural areas. In my estimations it was brighter than the Milky Way and as bright as the Magellan Clouds but the clouds were very high in the sky and the comet close to the horizon so it’s probably brighter.

Dawn of the Comet

Dawn of the Comet

Lovejoy will now begin to travel fast away from the Sun towards the south celestial pole. It will be fainter each day and it will be higher in the skies of the south hemisphere. By January 8th the comet will be circumpolar at latitude 35 degrees south, that means it will be visible the whole night. It will not be visible by the naked eye but with binoculars or telescopes it promises to keep being a fantastic target.

This comet, discovered by an amateur astronomer, was supposed to be destroyed at perihelion it survived and displayed a fantastic show. It was a great christmas gift for all the people that like the beauties and surprises of the night sky.

You can find my photos of Comet Lovejoy at the special gallery I created on my website: http://www.luisargerich.com/lovejoy

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There are a lot of interesting astronomical events for photographers at the end of 2011, on October 21st we had the Orionids meteor shower, then Jupiter will be at opposition on the 28th. Venus starts to climb higher and produces some interesting conjunctions with the moon and mercury. Finally Mars also starts to climb higher in the sky and becomes brighter. The 2011 show ends on December with the 2011 Geminids meteor shower, always a reliable event even if the moon is bad for this year’s show.

I went out two nights, the 20th and 21st of October for the Orionids. The first night I tried from the coast of light-polluted Buenos Aires, I battled against winds of 40km/h and struggled all night long. The result: Zero meteors, I had hopes for a bright fireball to survive light pollution but it didn’t happen.

This is how the sky looked from my light-polluted spot:

Orion from a Light Polluted City

Orion from a Light Polluted City

Can you see Orion near the horizon? It’s difficult in the photo, easier with the naked eye.

Just before sunrise there was a nice conjunction between the Moon, Mars and Regulus. I took a shot from the same location before packing and going home:

Moon, Mars and Regulus

Moon, Mars and Regulus

For the night of the 21st I escaped to a rural area trying to win the battle against light pollution. It’s not easy when you live in a 10+ million people city like Buenos Aires, you need to drive more than 200km and even then you’ll find yourself near yet another city.

I drove to the County Observatory of Mercedes, 100km away from Buenos Aires. The observatory has nice rural skies, light pollution is only a problem in the direction of Buenos Aires to the East. Unfortunately Orion rises at the East so the battle was on again. The skies were much, much better and I managed to shoot two nice Orionid fireballs just before midnight.

Orionids from Argentina

Orionids from Argentina

The photo was selected as Amateur Astronomy Picture of the Day, thank you!

At 3am the moon emerged from the horizon and clouds rolled in, so it was time to go home. I took a shot of the cloudy nightscape with a fisheye lens to show how bright Jupiter was near opposition.

Jupiter at Opposition

Jupiter at Opposition

Jupiter shines at -2.7 magnitude you can compare it against the brightest star in the sky: Sirius at the top right of Orion. The Pleiades cluster is also visible in the photo. Even with the clouds you can see many more stars from this rural location than from a light polluted place. I will try to be in an even darker place for the Geminids, it just needs some weather help.

Finally a Stellarium capture of the Conjunction between Venus, Mercury and an ultra-thin moon just after sunset for October the 28th. If weather is good don’t miss it!

Moon-Venus-Mercury on October 28th

Moon-Venus-Mercury on October 28th

As usual I’ll be posting the photos as I process them in my Nightscapes Gallery at my website.

I have also added a new option for Matted and Mounted Metal Prints at a good price in the strange event of a visitor liking one of my photos 😉

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Omega Landscape

Omega Landscape

Omega Centauri is the biggest and brightest globular cluster in the sky. It’s only visible from the South Hemisphere and on a dark location it’s very easy to see with the naked eye and a great view with binoculars.

There are a lot of great astronomical photos of Omega Centauri available but only a few showing the Globular Cluster in the context of a landscape or as we call them at night a “nightscape”. In my research I only found a very nice photo from the great photographer Tunc Tezel at Twan (link).

So I went on the task to photograph the King of all clusters in a landscape contest. The photo taken with a 135mm lens simulates what can be seen from a very dark location. The cluster looks small but compare it with the stars around it and you’ll see how big and bright it is.

Most people think “you took a black photo” or “poor Luis forgot to remove the cap lens again”, you need to see it as large as you can in a dark room, then it’s better, I promise.

I think this is a way to show a beautiful and unique astronomical object in a context that doesn’t need telescopes or special equipment.  If you examine the photo carefully (click to go to my site then click again for a larger view) you will be able to find a small and beautiful galaxy: Centaurus-A (NGC 5128) and more eye-work will show you a galaxy similar to our own Milky Way: NGC 4945. Can you find them?

Now I need to find a way to print it, nightscapes aren’t easy to put on paper.

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