Martian clouds

On telescopic observation , analysis of Martian weather activity is the most important job .

On Mars there are many types of clouds , and as the time of the Martian year , we can expect some clouds .

The crystal clouds of carbon dioxide and water , can be notified in direct view full light or green filters , blue or violet . Dust clouds or dust storms are best detected mainly in orange and red filters .

Although it is difficult to identify novice observer Martian clouds , it is considered that the continuous observation of the planet , determines an increasingly familiar relationship with areográficos accidents . After a few days of observation , the vision becomes sharper , so it can be distinguished jutting some sparkles on the surface of the planet , especially if these luminosities are located in regions that are typically more opaque . These flashes are the Martian clouds and are best viewed with the use of colored filters .

This cloud can be classified into the following types :

A) mists LIMBO ( in English: Limb Haze ) appears as a bright arc on the rising or setting the planet limb . It is caused by the oblique view of the Martian atmosphere with its suspended aerosols : ice crystals in cirrus type , crystals CO2 , fine dust or a mixture of these components . They disappear from 8 or 9 hours or come to 16 or 17 pm local time on Mars. When they are high are best visible with

violet filter ( composed of crystals of CO2) and are low , are visible with green blue filter ( crystals CO2 or water vapor ) or ( due to mixing with the yellow dust of the ground) .

The observer can not experienced confuse them sometimes with some possible optical phenomenon the telescope . The certainty only occurs when you best image clarity : if fog is quite evident and if it disappears optical phenomenon .

B ) CLOUDS OF LIMBO ( in English: Limb Cloud) : It is the largest of a condensation fog, making them brighter and visible even in the absence of filters . They are common in the early morning , may extend slightly beyond the planetary edge and disappear after the birth of the Sun is a type of cloud that limbo is also noted near the terminator of Mars and is known as morning clouds and afternoon . The morning clouds , are sometimes associated with the haze near the limbus morning frosts . So are best seen in greenish blue filter , blue and even yellow. The fog dissipates midmorning , while the frost can persist for most of the day , depending on the season . Afternoon clouds are generally larger and more numerous than the morning clouds . They appear as isolated bright spots on clear desert regions in late afternoon and tend to grow dark. Are best seen in blue filters .

C ) orographic CLOUDS : They are white and discrete spots that appear high in the mountains , especially in volcanoes of the Tharsis and Elysium region . In 1997 , orographic clouds from the volcano Olympus Mons appeared as a light snowflake in the middle of the planetary disk , visible even without the use of filters (see Sky & Telescope September 1997 magazine page 102 ) . When seen in the west, these clouds so bright that reached photometric values ​​of 0.2 . However , in 1999 , Tharsis orographic clouds were darker than the Elysium .

The formation of punctate clouds at each volcano Tharsis , because clouds folkloric settings known as the " domino " or as "W" if they coalesce up . They consist of water vapor and are best seen in blue and violet filter. They usually occur in the afternoon and late in the day and can become as bright as a polar cap .

D ) CLOUDS OF DUST AND DUST STORMS : Are rapid formation but take weeks or months to dissipate . They move and cause reduction of the definition of dark markings on the planet . May be precursors of the great dust storms . They usually arise in Solis Lacus , Hellas - Noachis , Isidis , Chryse and Casius - Aetheria . Are best visible in orange or red filter . If the usual format of albedo spots deform in relation to previous days and also be a highlight in brightness when viewed through red filter , dust or even think about dust storm .

E) CLOUDS OR DISCREET LOCATED : . Clouds are appearing anywhere on the planetary disc. Some are formed in the early morning and another in the evening . They may persist for several days , grow and move up . Some are topographical nature , arising in large plans , valleys , basins ( Hellas and Argyre I) and deep craters . They are very intense and bright as to be seen even without filters . They are composed of ice crystals and dust , often from the sublimation of surface ice.

Source : REA / Brazil

In the attached photo we can distinguish a perfect Orographic Cloud ( NO) near the center of the planet , this cloud that was also recorded by Mr Martini at 07:11 UT .

Stacking only 646 frames due to bad seeing at AS ! 2

Processing ; Registax , Photofiltre and Irfan