Local:Vale do Rossim - Serra da Estrela
Milky Montain
This Summer night couldn't have been more perfect: dark sky (magnitude 6,5 and SQM 21,30), without clouds ( even the threatening from the coastal horizont, (the most insolent were ripped by the mountain), no wind or cold (12º), absolutely no humidity, and the good Seabra's company , Fausto's and respective families. The Vale do Rossim den is just a little below of Penhas Douradas at about 1430 meters of altitude.
Skies of this rank have the particularitity of being a true delight to the naked eye vision, it can be counted by one hand fingers the moments that I had the chance to see such extensive Summer Milky Way , tearing the sky from the Scorpion's tail to the Perseu's legs, crossing horizon to horizon with abnormal density, turning the brigher constellations almost unrecognizable imersed by stars emerged from the sky's blackness, having some of the modest constellations gained form and make then more worthy of their named. Under dark skies, our own Galaxy becomes the most amazing object, being simply necessary a pair of eyes to have the sensation that we are really part a much biggerr picture, despite many times I experiencie it , will always be a fascinating vision. The trip was worthy for this alone.
Grabbing a pair of binoculars it was possible to walk with a little more detail on the no-end of star's rivers and valleys of interstellar dust, with the small concentrations that marked the clusters, as well as some nebular regions, like the gigantic "North America" or even the Helix Nebula which on the binoculars reminded me the one that I saw at La Palma. During all night the much closer sporadical meteors falled , with some announcing the Perseids, and with some of them fragmented and lefted a illuminated dust track.
 Pipe Nebula |
Using the Sky90, I started on Sagitarius on the scene of M8 and M20 sharing he same field, slowly going up to the Shield where is located the M11 and M26 open clusters. When I looked at it at 21x, I better associated the given nickname “Wild Ducks” , because with this magnification and aperture it really has a similar form to a well compacted flock of birds, even immersed om a cloud of stars.
I finally was able to observe the Barnard's galaxy (NGC 6822) using only 21x, likewise as previously seen on the 8", this galaxy stiil is a extremely diffuse object , having initially to move the telescope to detect its presence, and with some insistence a direct vision vision object. On the Seabra's 18 "its elongated shape was quite notourious. Also the extraordinarly bright neighbor,the small planetary NGC 6818 “Little Gem Nebula ”, announced its presence at only 56x, but still a small diffuse ball. Still in the region I made a visit to the globulars M55 and M75, being the former quite big with dozens of resolved stars , and the latter almost its antithesis: small e without practically any resolution. I was however sufficiently surprised with the resolution I got from the M15, this one already in the Pegasus. I still I tried to detect NGC 891 in Andromeda, but I guess to need deduct one or two more kilometers from atmosphere to get this one, remaining of this attempt just the vision of the pretty yellow pair and blue Gamma Andromedae (Almach). I pass by the a M31 that panned across the three degrees plus given by the 24mm eyepiece, that also included the satellite galaxies M32 and M110 all in a beautiful framing.
The start of the twilight was a true parade of artificial satellites with prominence for the ISS and a triangular formation of satellites, that according to Heavens Above were US Navy NOSS 2-1 (c) “top-secret ” monitoring military satellites. These satellites are normally discrete, shinning at about magnitude 5, but in this in case that they had presented at least a magnitude 2 the 3, by rough estimate forming a triangle with 3 degrees side, what it gives to appreciate what the 60, 50 km are like seen at about 1000 kms distance. To learn more click here. After seeing the pair Space Shuttle and ISS soon after its separation some years ago, is always good sign to see these free fall machines at the beginning of the night and better sign yet if at the end of the night.
Speaking of photographs, I did not resist to grab some souvenirs from this dark sky. It is always a rare pleasure to be able to do 4, 5 minutes exposures without a filter at f/4.5 and to not saturate the images. Below are images of two of the biggest apparent dimension galaxies from the Northern hemisphere, the Andromedas's M31 and friends and the Triangles's M33 Galaxy. Both reasonable under-exposed with just 20 minutes (5x4 minutes) each, but I guess enough to capture the general idea. The image of NGC 404 (“Ghost of Mirach”) was a focusing test with only 2 minutes, but it is an image of the uncommon pair there that is mentioned in the report below.
 M33 (clique na imagem - click on the image) |
 M31, M32 M110 |
 NGC 404 and Mirach |
22/07/2006
Local:Atalaia (Montijo 38º44N 8º48W)
Atalaia XXV
It's been a while since the last visit to Atalaia.
The night was quite good, with a limiting magnitude around 6, with a Milky Way a instantaneous sight. Some periods where some humidity fell and some clouds passed. Good transparency and low turbulence.
It had planed to start the night trying to split Antares with the 90mm, but a unexpected problem didn't allow me to be at the hour of its transit by the meridian. I followed then for a type of stars that had made me curiosous. The reddest and coldest that can be observed - the carbon stars.
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Carbon stars have luminosities that range from dwarf to giants and are in the phase of carbon fusing, freeing vast amounts of this element to their atmosphere and to the interstellar medium.
These stars have the particularitity to present on their spectra wide absorption lines from carbon constituted molecules, responsible for the absorbing most of the blue light, that combined with low temperature results in extremely red visual appearance. It is the case of the 7.5 of magnitude star T Lyrae (SAO 67087, HIP 90883), that if it was “a normal” star would be classified as M5 or M6 with temperatures to go up to around a somewhat mild surface temperature of 2000 K, but due to high abundance of carbon locally produced, creates a filter that reddens the star even more being possible to observe through a small telescope.
With the Sky90 it could be described as a red-orange point , with the impression of havinglower brightness than the indicated magnitude . On Alberto's 15 " Obsession the its color was a spectacular SPA of red light.
Its spectral classification is C6,5 (R6) where 6 is the temperature (decreasing from 0 to 9) and the 5 the “force” of the carbon lines (increasing from 0 to 5). The most current classification however points to C8. The very cold stars are hard to characterize, even Hipparcos give a distance of 2060 ± 980 year-light, a luminosity of 310 ± 300 x of the Sun and an absolute magnitude of -1.4 ± 1.0. View not to miss not very far from Vega.
The small square above are trail stars from an 30 seconds image to show (or better to spread) its different colors. The reddest star is T Lyrae and the next HK Lyrae another carbon producing star, the bluest star is a B9. The image below is a clip from the same region and has close to 1 square degree around T Lyrae.
 T Lyrae (clique na imagem - click on the image) |
Next I placed the UHC filter and I gave a tour by the Swan, starting by the " Veils" where almost observed the great “parenthesis” formed by the both segments. This time the “North America” also included all Canada and perhaps the state of the Alasca - nebulosity all over the field of the panoptic 24mm three degrees could deliver. I passed then to the challenge object - the nebula NGC 6888 also known by the name of “Crescent”. I wasn't very hopeful to see it with just 90mm, but for my astonishment I guessed its presence without the UHC filter . At 21x it can be described lke a small area of faint nebulosity in the neighborhoods of a triangle of relatively bright stars, nowhere similar to an crescent, but the most important in this in case was the positive observation with a small telescope. I finished with a quick look to the bright planetaries, NGC 6826 and NGC 7027, and of course the M27.
Moving to another subject, I was gonne to the hunting of the exterior planets Uranus and Neptune. Uranus is shining at magnitude 5.8 and was easy to find with just 56x as a small fat star, very similar to a small planetary nebula. At 167x was without a doubt a small e uniform and very pale green-bluish disc. Neptune escaped to me completely. Its magnitude of 7.8 is by no means a challenge, but its size of only 2,35 ", is dangerously close to the size of a 90mm aperture Airy disc and proved to be fatal to be able to distinguish it from the stars. For the next time I'll have a map prepared.
By the end of the night, Cassiopeia constellation was already high enough so I gave a quick look to some of it's most interesting objects . The first one of them was NGC 7789 that although residing on very star populated region, is distinguished easily with just 21x. With a bit more of magnification (56x) resolves dozens of stars concentrated on a very diffuse area, being this cluster my favourite in this constellation.
I briefly passed by the NGC 457 ( “ET Cluster ”) on the way to NGC 281 (IC11), being this last one involved by the misty “pacman” and the challenge in this region. With the UHC filter it was possible to observe without difficulty that this region has a faint nebulosity, even so (again) it didn't the recognized the form that gave it's nickname. And still the mandatory visit to the “Double Cluster ”.
 NGC 7789 (clique na imagem - click on the image) |
After another quick look at the Andromeda galaxy and its two satellites I moved to a galaxy that couldn't be better marked, at only 8 arc-minutes from the orange Mirach, the Andromeda's beta star . The dwarf eliptical/lenticular NGC 404 is a small round nebula with magnitde 11, but enough condensed to even survive the bright neighbor's emitted light . It is quite more accessible than some Messiers.
And finally the aged Moon rised sporting a phase close to 4% illumination, but from my site still took some time to show up from the trees that cutted the horizon. But the sight that it gave with Venus (shinning at -3.9! at only the five fingers from the Moon) made the penalty to see the day born at Atalaia's. The earthshine was surreal, and nice closing end of a well spented night.
As usual some images and reports at www.atalaia.org.
 Crescent (clique na imagem - click on the image) |
 The twighlight |
19/07/2006
Local:Pátio (Leiria 39.75N 8.82W alt:60m)
"Perfect Thunderstorm"
Another great Summer thunderstorm. This one in particular was of most active than I have yet observed. A mosaic of some more spectacular rays and a composition of 6 photographs of 30 seconds with Nikon D70 zoom 50mm at f/4 during a period of 3 minutes. I know where I would not like to be...
 (clique na imagem - click on the image) |
 (clique na imagem - click on the image) |
07/07/2006
Local: Praia da Rocha - Algarve
Death Ray
This photograph made me remember a scene of one any alien attacks movies. Of fact it is only the consequence of the Moon already in advanced age reflecting on the sea helped by a difraction and refraction effect. Took the photo of the top of the rock that gave the name to the beach.
 Death Ray Nikon 950 - 8 seconds |