Mars 2005 - 2006
From SkyInsight
By: Jeffrey D. Beish
During 2005 Mars will not be as close to Earth as it was in the last apparition of Mars in 2003; however, it will be higher in our sky so every astronomy enthusiast will have the opportunity to see and enjoy Mars. We want to heighten your awareness of Mars in the coming year and, by explaining what kinds of observations are possible and how you could be making such observations, enlist your support as a Mars observer.
What the Mars Section of the Association of Lunar and Planetary Observers (ALPO) are asking you to do – sketch and take images of Mars from your backyard - may seem old-fashioned and unscientific compared to the accomplishments of the space missions to Mars. These missions mapped geological features and monitored atmospheric phenomena of the planet from orbit. But the spacecraft for monitoring atmospheric conditions of Mars are no longer in operation. Until the next missions reach Mars, everything we learn about Martian phenomena will come from terrestrial telescopes - and amateur planetary observers.
Despite centuries of surveillance by Earth-bound astronomers armed with powerful telescopes and two decades of close scrutiny by orbiting spacecraft, much of Mars remains an object of mystery and intrigue. Important scientific questions about the long-term conditions of the Red Planet remain unanswered. You can help us answer them.
It falls to the visual observer armed with a 4-inch or larger telescope to keep an eye on Mars and to report observations to the astronomical community. What's required is enthusiasm, persistence, dedication, and care. Keeping a Watch on Mars
Viewing with the human eye is the most sensitive way to record features of planets. The human eye and brain readily detect subtle patterns of light, shade, and color that even the best modern films miss. Because the eye records planetary features during successive brief moments of atmospheric stability, an observer with a small telescope can build up a detailed composite image of the planet in his mind. Transferred to paper as a sketch, that subtle detail is preserved for later study. If you have a 4- to 10-inch telescope, we would like you to sketch Mars for us.
Mars is the only planet with a surface that can be plainly seen and charted from Earth. Since spacecraft have photographed Mars, we know the gray-green features observers see on the Martian disk are a variety of structures, and the appearance and borders of these structures are modified seasonally or over the years by wind-blown dust. Visual observers can also document the shrinking of the southern polar cap, as Martian spring turns to summer and the snows thaw. During 2005-2006 observers will write another chapter in the observational history of changing Martian features.
For visual observers the Martian atmosphere offers more variety than any other Martian feature. In 2005 and 2006 you can watch white clouds form downwind from the big volcanoes, track the yellow dust storms as they build over the plains, and monitor the blue hazes in the atmosphere.
But seeing changes on Mars is only the beginning: an observer must transfer that hard-won detailed picture of Mars to paper - in the form of simple pencil sketches. Send those sketches and electronic images to an organization that can forge them and hundreds of similar observations into a coherent account of Martian behavior in 2005 and 2006, a vital function performed by ALPO. During the 2005 and 2006 apparition ALPO will work closely with Mars Watch '05, a coalition of professional and amateur astronomers, to educate the public and gather scientific observations of this intriguing planet.
We urge all interested observers to contribute visual observations,
black & white prints, color slides, CCD and web-cam images to ALPO
Mars Coordinators. The Mars Section of ALPO also produces up-to-date articles
and an electronic newsletter, the "Martian Chronicle," which can be viewed
on the A.L.P.O. Mars Section web page, at URL:
http://www.lpl.arizona.edu/~rhill/alpo/mars.html.
The 2005-2006 apparition of Mars will be one of the most favorable of the twenty first century for two reasons: Mars will be close to Earth, and it will be above the celestial equator in our sky.
While the orbit of Earth around the Sun is very nearly circular, the orbit of Mars is not. During opposition, when the Earth and Mars lie in line with the Sun, the distance between the two planets may vary considerably from year to year depending on Mars' position in its orbit. If Mars comes to opposition when it is farthest from the Sun (at aphelion), then it will lie 61 million miles from Earth. But if Mars reaches opposition when it is closest to the Sun (at perihelion), it will lie only 34.6 million miles from Earth. Perihelic oppositions occur every fifteen to seventeen years; the last two were in 2001 and 2003. In November of this year Mars will be past Perihelion, but is still considered a Perihelic apparition.
Figure 1. Graphs showing the relative positions of Earth and Mars in their respective orbits around the Sun. Left: show the seasons for each planet. Right: Shows the relative posits of each planet as it relates to cardinal points in each orbit.
Because of the way Mars' orbit is located in space, the very closest
oppositions occur when we see Mars against the stars of Sagittarius and
Scorpius, the southernmost constellations on the ecliptic. Thus the very
best oppositions occur when Mars is too far south for good viewing in the
Northern Hemisphere. This is what happened in 2003: the opposition was
closest it had been in nearly 60,000 years, but Mars was low in the sky
in the Northern Hemisphere. In 2005 Mars will reach opposition in the constellation
Aries just 15.6 degrees north of the celestial equator. For northern observers,
Mars will be 32 degrees higher in the sky than it was for the 2003 opposition.
Because the light from Mars will reach us via a shorter path through Earth's
atmosphere, we will have a better, sharper view of the planet.
At opposition Mars will shine as a brilliant yellow-orange beacon in the sky. Through a telescope Mars will at first present only a shimmering yellow-orange disk. To the visual observer viewing it at 80x magnification, Mars will appear as large as the Full Moon viewed with the naked eye. Mars is then 20.2 arcseconds in diameter. To place this in perspective, this is the angular diameter of a volleyball one mile away.
Your first views of Mars will not be exciting. If you begin observing this month or next while the disk of the planet is still small, you may not see any surface detail at all. Don't give up.
As Mars comes closer to Earth during June and July, the disk will grow dramatically and move higher in the sky. During this time, when the disk is small, you must train your "observing eye" to detect the delicate contrasts of the planet, so when Mars nears its maximum size at opposition, you will be ready.
Under excellent seeing conditions a 4-inch telescope should give a sharp image at 200x; an 8-inch may be able to handle magnifications as high as 400x. Generally the best and sharpest views will be at medium-high magnifications of 30x to 40x per inch of aperture or 240x to 320x for an 8-inch telescope. But on nights when the air is still and calm, magnifications of 50x per inch of aperture may prove useful if your telescope has good optics.
In a 4-inch telescope you'll be able to see large surface features, bright clouds, bright limb arcs that occur when there's a lot of haze in the Martian atmosphere, large dust storms, the expansion or shrinkage of the polar caps, and "blue clearings" that occur when the Martian atmosphere becomes unusually clear to blue-violet light. Because of the limited resolution of a 4-inch telescope, you'll be able to see these features for only about ten weeks on either side of opposition while Mars is nearby and large.
With a 6-to 10-inch telescope you will be able to follow the same features for twelve to fourteen weeks on either side of opposition, and near opposition you will be able to see smaller clouds and dark features than you could with a 4-inch telescope. You can follow the advance and retreat of the polar caps in fine detail and check for irregularities in the polar cap boundary. You can also watch for changes in the shape and extent of the Martian surface features. Change may occur after major dust storms.
A telescope of 12 inches or more in aperture can make any of the features above easier to see and increase the quality of your observations. You will also be able to check for subtle changes in the color of surface features and clouds. One of the most valuable contributions you can make with a larger telescope is a uniform series of high-resolution photographs of the planet in color or in black and white.
On April 07, 2005, two weeks after spring begins on Earth, Mars will appear in the early morning sky as a samll disk 6 arcseconds in diameter at 18° south declination. Between April 07 and October 10, Mars will move steadily northward at one and a third of a degree per week. From the June 21, 2005 (summer solstice on Earth) through early March 2006 it will appear larger than 6 seconds of arc and remain above the celestial equator, well placed for viewing in both hemispheres.
The Red Planet's closest approach to Earth occurs at 04:21 universal time on October 30, 2005. Mars will also reach its maximum disk diameter: 20.18 arcseconds. Between October 20 and November 06 Mars will exceed 20 arcseconds in diameter.
Mars reaches opposition to Earth at 08:20 UT on November 07, 2005, when it is slightly farther from Earth than it was at closest approach. At opposition Mars rises at sunset and is highest in the sky an hour after midnight. For three months before and two months after this date - from August 10 to January 02, 2006 - Mars will be over 12 arcseconds in apparent diameter and close enough to Earth for careful observation.
The very smallest Martian features will be visible for nearly a month in 2005. Beginning on October 23 and extending through November 06, the disk of Mars will exceed 20 arcseconds. During this interval the large volcanoes, like those located within Elysium or in the Tharsis regions, may be visible even in a 6-inch telescope.
After opposition the Red Planet will linger near the same declination for several weeks then move farther north and into the evening sky, but it will be receding from Earth and becoming smaller again. Small surface details and faint atmospheric phenomena can be seen when an apparent disk diameter of Mars exceeds 12 arcseconds. You can see why persistence is a necessary trait of the Mars observer - you'll still be observing Mars in March 2006.
Figure 2. As it approaches Earth, it will swell from a small apparent disk of 6" in April 2005 to a maximum diameter on October 30, 2005, and then shrink as it moves away. Opposition occurs on November 7, 2005. April 2005 throughout February 2006 are the prime observing months.
What Features of Mars to View
Of all the worlds in the solar system Mars is most Earth-like. It has ever-changing weather, seasonal thawing of polar ice caps, clouds, vast dust storms, and four seasons. The changes are what you want to observe.
But to recognize changing features on the Martian disk, you will have to learn the dark markings and features that stay the same or change only slowly. These features will serve as your reference marks. Use the maps of Mars that accompany this article to learn these features as Mars approaches Earth this spring. During the three or four months closest to opposition you will be able to spot changing features - clouds, dust storms, the recession of the polar cap-with a skilled and practiced eye.
Astronomers have mapped Mars with a latitude and longitude grid just like the one on Earth, except that longitude runs from 0° to 360° continuously for Mars. (Earth longitudes run 180° east and 180° west from Greenwich, England. Mars is easier to understand.) The Central Meridian is the Martian longitude crossing the center of the disk of Mars.
To learn the Martian features, you need only look up the Central Meridian of Mars that’s facing Earth on a given day and hour and compare it to maps and drawings of Mars on this page to know which "face" of Mars you're looking at.Mars rotates once on its axis in 24 hours, 37 minutes, and 23 seconds. The Martian day, called a "sol" by space scientists, is thus a bit longer than a day on Earth. Mars turns only 351° of longitude in twenty-four hours. Consequently, if you observe Mars with your telescope at the same time each night, the Martian surface features will have turned 10° less far onto the visible side of the planet. (Thirty-seven minutes later, of course, Mars will be oriented exactly as it was the night before.)
Table I. At transit time (when Mars is at the highest altitude during each night) -- what Martian feature will the observer see? The Central Meridians (CM) are shown at transit time in UT and indicates one of the major Martian features you might see near the CM at that time. To find the Central Meridian for other dates and time, subtract 9.2° for each day after a tabulated date then add 14.6° for each hour after the tabulated time. Table covers a week before and after opposition.
| DATE (UT) | TRANSIT
TIME (UT) |
CENTRAL
MERIDIAN |
MAJOR FEATURE |
| Oct 18 | 0655 | 69° | Solis Lacus |
| Oct 21 | 0640 | 38° | Erythraeum Mare |
| Oct 24 | 0625 | 8° | Meridiani Sinus |
| Oct 27 | 0609 | 338° | Sabaeus Sinus |
| Oct 30 | 0553 | 307° | Deltoton Sinus |
| Nov 01 | 0543 | 287° | Syrtis Major |
| Nov 04 | 0526 | 257° | Tyrrhenum Mare |
| Nov 07 | 0510 | 226° | Hesperia |
| Nov 10 | 0454 | 196° | Trivium Charontis |
| Nov 13 | 0438 | 166° | Sirenum Mare |
| Nov 16 | 0422 | 135° | Olympus Mons |
| Nov 19 | 0407 | 105° | Phoenicis Lacus |
| Nov 22 | 0352 | 75° | Solis Lacus |
| Nov 25 | 0337 | 45° | Chryse - Xanthe |
| Nov 28 | 0323 | 14° | Margaritifer Sinus |
The net effect is that each Martian feature can be seen best every thirty-six days by an observer at a given longitude on Earth, but someone living on the other side of Earth will see the other side of Mars. Thus, for good coverage of Mars, ALPO would like observers all around the world to sketch and photograph Mars and report these observations.
Figure 3. Albedo feature maps prepared from ALPO/IMP data by D.M. Troiani and D.P. Joyce. The maps cover three apparitions: 1992-1993 (top), 1994-1995 (middle), and 1996-1997 (bottom). Methods of position measurement are described in the text. Each map was derived from analysis of several hundred observations, photographs, and CCD images.
An observer with a well-made telescope can contribute valuable Mars observations. However, it is important to learn certain standard techniques and use standard reporting methods so your observations can be compared to and used with reports from observers around the world. <p>Your telescope must have good optics, it must be properly collimated, and the optics must be clean so they can give the best contrast. You should observe from an open grassy area, away from asphalt, concrete and tall structures that soak up daytime heat and release it at night causing turbulence, or "bad seeing." City lights don't harm planetary observing, so you can observe Mars even from Miami or Los Angeles! But you must allow your telescope to reach outside temperature before attempting any critical observing, and you must conscientiously work at educating your "observer's eye" with lots and lots of observing.
You will need good quality eyepieces, but you don't need the expensive wide-angle types. A set of color filters is tremendously helpful but not absolutely necessary. Color filters increase contrast between areas of differing color, permit you to separate clouds at different levels in a planetary atmosphere, and reduce light scattered from a too-bright planetary image. All told, they increase the sharpness of surface and cloud details you will be trying to observe on the planet Mars.
A yellow filter brightens the ocher-colored Martian deserts and darkens the greenish and brown features. Orange filters increase contrast between light and dark features, penetrates atmospheric haze, and helps you see yellow dust clouds. Red goes even further, yielding maximum contrast of surface features and helping you see dust clouds.
Green, blue, and blue-green filters brighten atmospheric features and darken the surface. Violet filters go even further, bringing out haziness on the limb of the planet, small equatorial clouds, and clouds over the poles.
Used intelligently, filters help you see more than you could any other way. You can buy glass filters from companies that advertise in Sky and Telescope Magazine or obtain gelatin filters from a camera store. Your filter set should include all of the colors mentioned above, plus magenta to enhance polar cap contrast.
Many potential planetary observers say they can't draw, so they never even try to make planetary drawings. But drawing planets is not fine art. Instead it's a careful record of what you saw with your telescope. An ugly drawing is just as useful as a masterpiece so don't let any lack of artistic ability stand in your way.
Index cards are perfect for planetary sketching. Put one observation on each card, and be sure to include all relevant information on the card. Cards are convenient at the telescope, easy to stuff in the pocket of your shirt or coat, and easy of light on the sunrise or sunset limb of Mars. It appears at the limb because there the observer looks through a long path in the upper Martian atmosphere, which may contain carbon dioxide crystals, fine dust, cirrus-type water clouds, or a mixture of these. Consequently the presence of limb haze is a very sensitive way to detect unusual weather activity or polar phenomena. When you see haze, note its location, color, and density, as well as the filters used to see it.
Figure 4. Sequence for sketching Mars. Suggestions for a six steps drawing sequence of Mars at the telescope; 1) Draw 42mm or 50mm circle. 2) Draw phase terminator, if present, 3) draw polar cap(s), south at the top and north at the bottom, if either or both visible, 4) fill in rough outline of surface features, 5) darken familiar features and fine details, and 6) draw in clouds/haze detail in separate drawing disk. Drafted by J.D. Beish
Fogs and frosts, often called bright patches, form in the chill of the Martian night, rotate with the planet, bake off in the morning sunlight, and usually disappear by local noon. You can tell them from elevated clouds by examining them with blue, blue-green, and yellow filters. High clouds look brightest with a blue filter, while low-lying fogs look brighter with a blue-green filter than they do in a blue or a yellow filter. Surface frost looks brightest in green and yellow filters and is hard to see with a blue filter.
The behavior and location of bright patches also help distinguish these patches from clouds and limb haze. Fogs normally form in valleys, linear depressions, basins, and on upper slopes. Frosts are usually seen on deserts, plateaus, mountains, and floors of large craters. Pinpointing the location and seasonal occurrence is important to the study of Martian weather patterns.
Mars normally shows only a bright, featureless disk in violet light because the Martian atmosphere scatters short wavelengths. When a violet clearing occurs, the large, dark surface features can be seen through the atmosphere with a Wratten 47 filter. Although the debate over the cause of this phenomenon has raged for decades, no explanation of violet clearing is generally accepted.
Observations of Mars indicate that dust storms occur around the time of southern summer solstice, soon after Mars reaches perihelion. However, accurate predictions are nearly impossible to make because of the complexities and unknown variables. When a great dust storm reaches maturity, Mars' disk appears bright orange and Mars' surface features are obscured.
The Martian dusty season will begin about the first week in July throughout the middle of August 2005. The highest probability of dust storms occurring will be on or about July 24, 2005 and a sensitive area for the development of dust storms is in northwest Hellas.
Another sensitive period following the "procurer" storm season will come at the end of October when observers should be alert for dust clouds in the northeast Hellas Basin, the Serpentis-Noachis region, and the Solis Lacus region. 2005 may be a time when Mars may be very dusty indeed! What does this mean for the amateur observer?
For those interested in catching a glimpse of possible "flashes" from the surface of Mars there will be two periods when possible "flashes" may be seen on Mars. The first occasion when the De and Ds are coincident will be on or about July 04, 2005 and again be on or about November 08, 2005. In the tables below the Rise and Transit are in Universal Time (UT), De is the Declination of Earth from Mars (degrees), Ds is the Declination of Sun from Mars (degrees), De - Ds is the coincident (degrees), and i = phase defect (degrees):
| Date | Rise | Transit | De | Ds | De - Ds | i |
| June 30 | 0533 | 1143 | -22.2 | -21.3 | -0.9 | 47.1 |
| July 01 | 0532 | 1141 | -22.1 | -21.4 | -0.7 | 47.2 |
| July 02 | 0530 | 1140 | -22.0 | -21.6 | -0.4 | 47.2 |
| July 03 | 0528 | 1139 | -21.9 | -21.7 | -0.2 | 47.3 |
| July 04 | 0526 | 1137 | -21.7 | -21.8 | 0.1 | 47.3 |
| July 05 | 0524 | 1136 | -21.6 | -22.0 | 0.4 | 47.3 |
| July 06 | 0522 | 1134 | -21.5 | -22.1 | 0.6 | 47.3 |
| July 07 | 0520 | 1133 | -21.3 | -22.2 | 0.9 | 47.3 |
| Date | Rise | Transit | De | Ds | De - Ds | i |
| November 06 | 2235 | 0519 | -15.1 | -15.9 | 0.8 | 1.3 |
| November 07 | 2231 | 0514 | -15.3 | -15.7 | 0.4 | 0.5 |
| November 08 | 2225 | 0508 | -15.5 | -15.5 | 0.0 | 0.6 |
| November 09 | 2220 | 0503 | -15.6 | -15.3 | -0.3 | 1.5 |
| November 10 | 2215 | 0458 | -15.8 | -15.1 | -0.7 | 2.4 |
CCD or web-cam imaging has become a valuable adjunct to visual observing. Processed images constitute a permanent, impersonal record that can be studied later. Even images that do not seem particularly sharp may reveal cloud features on careful examination. If you have an 8-inch or larger telescope and an interest in astro-imaging, we would like you to photograph Mars for us.
Above all else we're looking for observers who want to stick with a regular Mars observing program for at least six months during the 2005-2006 apparition of Mars. We'd like to work with you to document the changing features of the Red Planet in 2005 so we can compile a better record of the planet than has ever been compiled before.
We also encourage astro-imagers to shoot and send us well-documented images of Mars. Observers who own or have access to large telescopes can best contribute to this work. Color slides or black-and-white prints are also useful; black-and-white photos and CCD images taken through color filters are especially valuable.
We hope observers who don't have the time to sketch Mars every clear night will observe Mars whenever possible just for the fun of it. Mars is a magnificent planet, and we'd love you to experience it.
| DATE | PHYSICAL | REMARKS |
| 2005 Mar 23 | Ls 180.1°
A.Dia 5.6’’ |
Equinox - Northern Autumn/Southern
Spring . South Polar Cap (SPC) maximum diameter, subtending ~ 60.5° W. Is the North Polar Hood present. Does SPH or frost cover Hellas? Hellas should begin to clear and darken. Are W-clouds present? South cap emerges from darkness of Winter. SPH thinning and forms "Life Saver Effect." |
| 2005 Apr 07 | Ls 188.7°
A.Dia 6’’ |
Apparition begins for visual observers
using 4-inch to 8-inch apertures telescopes and up. Begin low-resolution CCD imaging. Views of surface details not well defined. Southern clouds frequent. SPH hood thinning. Eastern Syrtis Major fading and broading? White areas brighter? Syrtis Major thinner and darker? Surface increasing in contrast. Hellas bright? Northern clouds frequent. Are both polar hoods visible? SPC should be free of its hood. SPC shrinking ? Possible W-clouds in Tharsis-Amazonis. NPH bright. White areas brighter? (SPC W ~58.1° ±5.5°). |
| 2005 Apr 27 | Ls 200°
A.Dia 6.6’’ |
Bright SPC projection Novissima
Thyle 300° - 330° areographic longitude. Dark rift Rima Augusta connected from 60° to 270° longitude. Rima Australis visible in SPC (290°-350°W)? W-clouds possible. SPC bright projection Argenteus Mons (10° W - 20° W). SPC Dust clouds in Serpentis-Hellespontus, in Hellas or Noachis? (SPC W ~52.8° ±3.5°). |
| 2005 May 13 | Ls 210°
A.Dia 7.2’’ |
Is the Rima Australis visible
in SPC (290°-350°W)? SPC bright projection Argenteus Mons (10°-20°W). SPC Novissima Thyle (300°-330°W) projection present? Look for possible small dust clouds in Serpentis-Hellespontus. (SPC W ~ 48.6° ±3.1°). |
| 2005 May 30 | Ls 220°
A.Dia 7.8’’ |
Bright SPC projection Novissima
Thyle 300° - 330° areographic longitude. Dark rift Rima Augusta connected from 60° to 270° longitude. Rima Australis visible in SPC (290°-350°W)? W-clouds possible. SPC bright projection Argenteus Mons (10° W - 20° W). SPC Dust clouds in Serpentis-Hellespontus, in Hellas or Noachis? (SPC W ~44.2° ±2.5°). |
| 2005 Jun 04 | Ls 223.6°
A.Dia 8’’ |
Syrtis Major darkens and continues
to shrink. W-clouds possible. Surface details increasing in contrast. Hellas bright? SPC Novissima Thyle (300°-330°W) projection present? Dark rift Rima Augusta connected from 60° to 270° longitude. W-clouds possible. Dust clouds? Is the Rima Australis visible in SPC (290°-350°W)? (SPC W ~41.4° ±4.1°). |
| 2005 Jun 30 | Ls 240°
A.Dia 9.3’’ |
Novus Mons small, bright, and
high-contrast. Rima Australis widens. SPC isolated bright spot at 155° longitude? Any white patches near -20° latitude may brighten. Atmosphere of Mars very clear during Ls 240°- 250°. Occasional morning limb hazes. (SPC W ~31.7° ±2.3°). |
| 2005 Jul 13 | Ls 248.2°
A.Dia 10’’ |
SPC rapid retreat. Novus Mons
small, bright, and high-contrast. Rima Australis widens. SPC isolated bright spot at 155° longitude? Any white patches near -20° latitude may brighten. Atmosphere of Mars very clear during Ls 240°- 250°. Occasional morning limb hazes. (SPC W ~29.0° ±2.8°). |
| 2005 Jul 16 | Ls 250.1°
A.Dia 10.2’’ |
Mars at Perihelion.
SPC in rapid retreat. Novus Mons smaller. Dust clouds expected over Serpentis-Hellaspontus (Ls 250° - 270). Syrtis Major narrow. Frost in bright deserts? Orographic clouds (W-clouds) possible. Elysium and Arisa Mons bright? Note: Several "planet-encircling dust storms have been reported during this season. High probability 255° Ls. (SPC W ~24.4° ±2.6°). |
| 2005 Aug 01 | Ls 260°
A.Dia 11.3’ |
Watch out for major dust storms,
first peak period for storms. Novus Mons reduced to a few bright patches and soon disappears. Hellas bright spots? Numerous bright patches. Windy season on Mars begins, dust clouds present? (SPC W ~20.6° ±0.8°). |
| 2005 Aug 10 | Ls 266.0°
A.Dia 12’’ |
Dust clouds in south? Atmosphere
clearing of blue clouds? Decreased number of White clouds? White clouds rare. W-clouds present? White areas in deserts? Dust clouds in south? Watch for planetary system clouds bands. NPH extends 50°N? (SPC W ~19.1° ±1.4°). |
| 2005 Aug 17 | Ls 270.4°
A.Dia 12.6’’ |
Southern Summer Solstice.W-clouds
present? NPH extends 50°N? Decreased number of White clouds. Atmosphere clearing of blue clouds? White areas in deserts? Dust clouds in south? (SPC W ~16.9° ±1.1°). |
| 2005-Sep-02 | Ls 280°
A.Dia 14.2’’ |
NPH extends 50° N? White clouds
rare. Dust storm? Frost patches? (SPC W ~14.3° ±1.3°). |
| 2005-Sep-18 | Ls 290°
A.Dia 16.2’’ |
Look for orographic clouds over
the Tharsis volcanoes. W-Cloud? SPC small. (SPC W ~ 9.8° ±0.9°). |
| 2005-Oct-05 | Ls 300°
A.Dia 18.3’’ |
Orographics over the Tharsis volcanoes
-- W-clouds present? SPC very small. Photography still possible. White areas? Look for orographics clouds (blue or violet filter). CCD and film imaging still possible. (SPC W ~10.7° ±0.9°). |
| 2005-Oct-21 | Ls 310°
A.Dia 19.9’’ |
Edom bright? Is SPC remnant visible
in mid-summer? High probability of dusty storm at 315° Ls. (SPC W ~6.3° ±2.4°). |
| 2005 Oct 30 | Ls 315.2°
A.Dia 20.2’’ |
Mars at Closest Approach.High-resolution
CCD imaging and photography. Watch out for major dust storms, second peak period for storms. Is SPC remnant visible in mid-summer? Edom bright (SPC W ~4.5° ±0.7°). |
| 2005 Nov 07 | Ls 319.8°
A.Dia 19.9’’ |
Mars at Opposition.
Watch out for major dust storms, second peak period for storms. Is SPC remnant visible in mid-summer? Edom bright. (SPC W ~5.4° ±0.5°). |
| 2005 Nov 26 | Ls 330°
A.Dia 17.7’ |
Hellas Ice-fog activity? NPC large hood present. W-Cloud? (SPC W ~9.6° ±0.3°). |
| 2006 Jan 01 | Ls 349.5°
A.Dia 12’ |
Views of surface details not well
defined. Large NPC hood present? Views of surface details still well defined. Some photography now possible. Discrete (white) clouds and white areas should be seen. NPC large hood (NPH) present. Syrtis Major begins to expand to its east. |
| 2006 Jan 19 | Ls 358.7°
A.Dia 10’’ |
NPC large hood (NPH) present.
Discrete (white) clouds and white areas should be seen. Syrtis Major begins to expand to its east. |
| 2006-Jan-22 | Ls 0°
A.Dia 9.7’’ |
Northern Spring/Southern Autumn
Equinox. North Polar Hood (NPH) breaking up, North Polar Cap (NPC) should be exposed and near to 55° areographic latitude. SPC very small, difficult to see. White areas? Orographic clouds over the Tharsis volcanoes. W-Cloud? |
| 2006-Feb-12 | Ls 10.5°
A.Dia 8’’ |
Hellas and Argyre bright? (NPC W ~35° ±3°). |
| 2006-Mar-23 | Ls 28.9°
A.Dia 6’’ |
Limb clouds and hazes should start to increase. (NPC W ~33° ±2.5°). |
