Merry Christmas & Happy New Year from ESAC

Merry Christmas & Happy New Year!

Joyeux Noël et Bonne Année!

Fröhliche Weihnachten und ein glückliches Neues Jahr!

Vrolijk Kerstfeest en een Gelukkig Nieuwjaar!

Buon Natale e Felice Anno Nuovo!

Boas Festas e um feliz Ano Novo!

Glædelig Jul og godt nytår!

God Jul och Gott Nytt År!

Eg ynskjer hermed dykk alle ein god jul og godt nyttår!

Kala Christougenna Ki'eftihismenos O Kenourios Chronos!

Feliz Navidad y Próspero Año Nuevo!

2007-12-01: Mars one month before the oposition

This post shows the results of our second tentative imaging Mars close to its oposition. In this case, the people meeting in Satan Hill were Leo, Michel, Roberto and me. Again, the Leo's Dobsonian 65 cm telescope was used together with a Toucam Pro webcam, blocking and pass NIR filters and a 3x Barlow. The captured video tracks were stacked with REGISTAX and the histograms modified to show the best contrast. Additionally, an unsharp mask was applied to enhance as possible the contrast of the surface details.

The following image was captured around 2:30 GMT with the NIR blocking filter.

The next one was captured around 2:30 GMT with the NIR pass filter.


A combination of both images substituting the red channel of the firs image with the second one produces the next image.


In the north cap, the winter CO2 froze can be observed extending to the south of the polar regions. Now, as the planet is closer, both the RGB and NIR images show more details of the surface than in our previous tentative. However, the poor seeing during the observation degrades the sharpness of the images. Despite that, the observed regions can be clearly identified. The following image has been produced by Leo forzing a little the sharpening to remark some of the Mars regions.

2007-11-07: Mars two months before the oposition

This post shows the results of our first tentative imaging Mars close to its oposition.

On November 7th, 2007, Leo and me were at Satan Hill in ESAC to try to image mars with the Leo's a Dobsonian 65 cm telescope. The following images show our best results with the Toucam Pro webcam, blocking and pass NIR filters and a 3x Barlow. The captured video tracks were stacked with REGISTAX and the histograms modified to show the best contrast.

The following image was captured around 1:30 GMT with the NIR blocking filter.

The next one was captured around 1:30 GMT with the NIR pass filter.

A combination of both images substituting the red channel of the firs image with the second one produces the next image.

The planet disk shows a well defined phase yet and both the RGB and NIR images show very well different details of the surface. The image is centered in Chryse planitia with Syrtis Major appearing in the terminator. In the north cap, the usual winter CO2 froze can be clearly observed far from the polar regions.

Comet 17P/Holmes

After some time dedicated to other astronomical topics, I'm back to share my images of comet 17P/Holmes.

This comet suffered a very spectacular eruption on Oct. 24, 2007. In less than 24 hours, the 17th magnitude bright of the comet increases by a factor of nearly a million, becoming a naked-eye object. From this day it has been expanding while it was crossing the constellation Perseus. Now, it is vanishing and it nos as spectacular than before but now it has a diameter bigger than the Moon that can be very well appreciated by the naked-eye from very dark places.

During the first two weeks the comet was bright enough to be observed from the center of the cities. Thus, I put my equipment in front fo the window and I captured the images I show you. All the images have been captured with a C8 SCT and a Canon 400D camera with exposures of 20 seconds at 1600 ASA.

The following image shows the evolution of the coma of the comet between 3 days after the eruption and one week.

The next image is an anagliph of the previous images using the aparent movement of the comet on the stars background. If you have red&blue glasses you can appreciate a 3D view of the comet in front of the stars.

An animated gif helps to evaluate the comet growth in during only one week.

The last image was taken with 30 seconds exposure on Oct. 30 at 19:30 GMT. Later the histogram was forced a little to show the exterior green halo of the comet. It is erupted matter that emits green light because its interaction with the solar wind. It is green because its composition and it can be well observed because this matter has not enough density to reflects sufficient solar light (mainly white) to mask this emission.

Additional images of the comet showing its evolution from the first eruption until now can be found in this webpage or this one.