Marswatch 1998-1999 Apparition Linking Amateur and Professional Mars Observing Communities.

Images - 1999 April 21-30
    (All times U. T. - Images not to scale. Click on image for more or larger scale views where available.)

21

Donald C. Parker, Coral Gables, Florida
Lynxx PC camera 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)     8.75-15.00s
   Green (VG9 + IR Rejection)    4.00-5.50s
   Red (RG610 + IR Rejection)   0.38-0.44s
Images flat and dark corrected.
Seeing fair to poor (4-5) but improved late (7). Transparency 5m initially but deteriorated late due to clouds, haze. Wind NE-ENE 2-10 knots. Slight dew.
Strong (3+) violet clearing southern hemisphere, 2+ in northern -- also noted visually with Wratten-47 filter. Syrtis Blue Cloud. Brilliant clouds over Hellas. Wispy haze over Libya; Elysium cloud brightened with rotation. Hyblaeus Extension broad, dark. Cerberus III noted. Cerberus-Trivium only 2-3 dots.

Frank J. Melillo

Bob Bunge; E-mail: rbunge@radix.net
4-inch f/10 reflector, 225x.

07:00 UT
Seeing: 9.2 out of 10.

Put the 4-inch reflecter out at 10 p.m. (EDT) and went to bed. Got up at 2:45 a.m. to high, thin clouds, no wind and temps in the upper 30's. Very calm. Thicker clouds appeared to be coming in from the west. Seeing rated a 9.2 out of 10. Of interest was the bright area called Elysium in the northern part of the disk, gently surrounded by dark markings (Stymphalius Lacus). Also clearly seen was Libya, the "inlet" on the side of Syrtis Major, as well as Moeris Lacus, the dark marking the forms the northern side of Libya. Alcyonius Nodus, a dark marking between Elysium and Utopia appeared larger, with more subtle details than shown in the maps published in Sky & Telescope. Also seen were faint dark markings that make up Protonilus, off the tip of Utopia. Mare Tyrrhinum, Mare Cimmerium and the light area between them - Hesperia - were easily seen in the south, wrapping around the Hellas bright area. Several dark and lighter areas on the north side of Tyrrhenum were visible. Also, the edge between Sytris Major and Aeria was mottled, with a good amount of detail seen. The North Polar cap continues to be somewhat difficult to see. All of this with a 4-inch telescope!

António Cidadão, Oeiras, Portugal
ST-5C camera 10-in (25cm) f/10 Schmidt-Cassegrain

Seeing conditions (7-8/10). Bright clouds over Elysium, Nix Olympica and Tharsis. Cloud over Arcadia.

Possible dust storm (or cloud?) over Mare Boreum (arrowed). This feature was absent on images obtained on April 18 and 19. It is now visible on R, G and B filtered images.

22

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

Donald C. Parker, Coral Gables, Florida
Lynxx PC camera 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)   10.50-11.75s
   Green (VG9 + IR Rejection)    4.50s
   Red (RG610 + IR Rejection)   0.41s
Images flat and dark corrected.
Seeing excellent (8). Transparency 5m initially but deteriorated late due to clouds, haze. Wind ENE-ESE 3-13 knots. No dew.
Strong (3+) violet clearing southern hemisphere, 1+ in northern hemisphere -- also noted visually with Wratten-47 filter. Syrtis Blue Cloud. Brilliant clouds over Hellas. Wispy haze over Libya; Elysium cloud brightened with rotation. Hyblaeus Extension broad, dark. Cerberus III noted. Cerberus-Trivium only 2-3 dots. Bright cloud noted in green and blue and visually with W-47 southeast of NPC over Lemuria.

Richard W. Wilhelm, Manorville, New York.
4.5" (11.4 cm) F/8 Newtonian.

Seeing: 9/10, transparency: 3/6.
A veil of high cirrostratus clouds triggered by an approaching warm front produced excellent seeing conditions. Primary albedo features strong in blue light (W80A), although not to as great an extent as 4/19. Uchronia, Utopia, Casius and Lemuria along with the Hyblaeus Extention highly visible and exhibiting a fine contrast with the surrounding desert regions. Hesperia seen, sharply dividing Mare Tyrrhenum and Mare Cimmerium. Syrtis Major partially obscured by morning haze/clouds, extending to Libya, with W15 filter revealing a partial Syrtis Blue cloud. Cloud over Nix Olympica on evening limb, accenting a substantial evening limb haze. Both morning and evening limb hazes were highly visible in red light. Some brightening seen over Xanthus/Ausonia region. Given the overall excellent visibility all features mentioned, it is interesting to note that I didn't see traces of the Propontis Complex (seen on 3/21 under less than ideal seeing conditions) or the nearby (presumably still existent?) Elysium cloud. In the latter case, small aperture may be the limiting factor. I'm looking forward to seeing what my fellow observers saw in this regard.

Maurizio Di Sciullo, Coconut Creek, Florida; E-mail: NimbusSky@worldnet.att.net
Starlight Xpress HX-516 CCD camera; 10" (25 cm) Excelsior Optics E-258 f/8 Newtonian, Eyepiece Projection @ f/47

Integration Times:
   400 - 510 nm:   0.19s
   490 - 590 nm:   0.15s
   610 - 720 nm:   0.22s
All images acquired with 700 - 1200+ nm block filter inline with eyepiece projection unit, True Technologies Dichroic Filters + IR block
No dark frame, flat fielding or bias correction applied. Camera operated in "Binned" (low-res) mode. All images are single frames, no co-addition or averaging performed, except for composite color image.

Seeing: Very poor; 2/10. Wind: calm, low humidity (~ 70%).
416 frames acquired, 3 of marginal value.

Seeing almost too poor to conduct credible observation. Haze over Hellas noted, along with limb haze over Syrtis Major, and to a lesser degree over Mare Cimmerum. White cloud noted over Elysium Mons. 400 - 510 nm and 490 - 590 nm bands showing bright feature on perimeter of North Polar Hood (NPH) at approximately 150° longitude, 83° latitude at perimeter of Olympia Planitia. Suspect frost, as observations made on 3 April, 1999, during periods of excellent seeing show same marking at stated location.

Stefan Buda & Bratislav Curcic, Melbourne, Australia (5km from the city centre).
Homemade CB211 clone CCD with a mechanical shutter; 10-in. (25.4 cm) f/16 Dall-Kirkham (homemade) + 3X Barlow (effective f/50). No filters.

Seeing average to good (~7), transparency average (mag 4).

23

Mark Schmidt, Racine, Wisconsin; 88.02861° W 44.72889° N; E-mail: rasastro@wi.net
ST-5C CCD camera; 14-in (36cm) f/10 Schmidt-Cassegrain, Projection at f/31.

 L_s: 128.7°; D_e: 18.1°; Diameter: 16.0” 04:32 U.T.; CM: 206.48°; Integration time: 0.15s
Seeing: #2 1/2; Transparency: 2 1/2 - 3 1/2 mag.

Filters: 23A and IR Rejection Filter, Murnaghan Instruments Filters. Processing: CCDSoft-Image Processing Software; Skypro-Image Processing Software

Denis Fell, New Sweden, Alberta, Canada (113.16°W, 52.55°N), email:dfell@telusplanet.net
Astrovid 1000 CCD camera, 8-in (20cm) f/10 SCT, Negative projection f/30, Wratten #21 orange filter. Processed with Snappy and Micrografx Photomagic.

04:30-05:00 UT, CM: 215°-222°.
Seeing Antoniadi III-IV, Martian diameter 15.99", D_e: 18.26, Phase .999

Darkest feature Mare Cimmerium and M. Tyrrhenum. Bright areas noticed over Memnonia and by Syrtis Major on the limb. North is up.

24

António Cidadão, Oeiras, Portugal
ST-5C camera 10-in (25cm) f/10 Schmidt-Cassegrain

The images obtained on the night 24-25 show plenty of detail, mostly the red filtered ones. For instance, a bright "ring-like" feature is located at the site of Nix Olympica (almost at CM in the 0:07 UT frame) . This and other details rotate along with the planet.

Propontis Complex is seen near the eastern limb and Solis Lacus at the western limb. Clouds are seen over NixOlympica, Arcadia, Tharsis and Ganges. Haze near the South Pole region? Ice (+ cloud?) near the North polar cap (apparently over Lemuria) remains visible.

I'm ready, and so is my 'scope and CCD camera, but rain has ruled these last few days :-(.

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

Donald C. Parker, Coral Gables, Florida
Donald C. Parker, Coral Gables, Florida
Lynxx PC camera 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)   8.25-8.75s
   Green (VG9 + IR Rejection)  3.38-4.00s
   Red (RG610 + IR Rejection) 0.34-0.45s
   Infrared (750-825 nm)           5.00s
Images flat and dark corrected.
Seeing excellent (8-9). Transparency 5m. Wind ENE-ESE 4-9 knots. No dew.
Strong (3+) violet clearing -- also noted visually with Wratten-47 filter. Syrtis Blue Cloud. Wispy haze over Libya and Amazonis; Elysium cloud brightened with rotation. Hyblaeus Extension broad, dark. Cerberus III noted. Cerberus-Trivium only 2 dots. Bright cloud noted in green and blue south of NPC over Lemuria -- Lemuria also bright but smaller in red.

Daniel M. Troiani, ALPO Mars Section Head, Chicago, Illinois, E-mail: dantroiani@earthlink.net
17 1/2" f/4.8 Newtonian, 478x. UT

03:38-03:49; CM: 193°;  L_s: 128°; D_e: 18°
Filters: W#80a, W#47, W#25
Seeing: 7/10;  Transparency: 6/6
Blue Clearing (0-3): 3

Clouds over SPR with both limbs very bright. Slightly bright cloud in Elysium.

Denis Fell, New Sweden, Alberta, Canada (113.16°W, 52.55°N), email:dfell@telusplanet.net
Astrovid 1000 CCD camera, 8-in (20cm) f/10 SCT, Negative projection f/30, Wratten #21 orange filter. Processed with Snappy and Micrografx Photomagic.

04:50-05:00 UT, CM: 212°.
Seeing Antoniadi IV, Martian diameter 16.00", D_e: 18.41, Phase 1.00

Darkest feature Mare Cimmerium and M. Tyrrhenum. North is up.

Carlos E. Hernandez (A.L.P.O. Mars Section)
8-inch (20-cm) f/7.5 Newtonian reflector at 305x and Wratten 23A, and 38A filters.

04:50 UT (CM: 211.0°, Filter: Wratten 23A (red), left)
06:00 UT (CM: 228.1°, Filter: Wratten: 38A (blue), right)
L_s: 128.8°, D_e: 18.1°; Dia: 16.0".

Maurizio Di Sciullo, Coconut Creek, Florida; E-mail: NimbusSky@worldnet.att.net
Starlight Xpress HX-516 CCD camera; 10" (25 cm) Excelsior Optics E-258 f/8 Newtonian, Eyepiece Projection @ f/47

Integration Times:
   400 - 510 nm:   0.18s
   490 - 590 nm:   0.15s
   610 - 720 nm:   0.20s
   Full Band   0.07s
All images acquired with 700 - 1200+ nm block filter inline with eyepiece projection unit, True Technologies Dichroic Filters + IR block
No dark frame, flat fielding or bias correction applied. Camera operated in "Binned" (low-res) mode. All images are single frames, no co-addition or averaging performed, except for composite color image.

Seeing: Mediocre; 4-5/10. Wind; calm, high humidity (~ 95%).
Mediocre, but consistent seeing allowed 2 sets of images to be acquired, approximately 35 minutes apart.

First set taken about 05:14 - 05:19 UTC shows Syrtis Major very close to limb, showing blue Syrtis cloud to particular advantage. Cloud is viewed from a line of sight nearly tangential to the planet's surface at that point. Compare to second set taken after 8 degrees of rotation, which shows haze, but does not show the cloud's striking blue color as well. Evening side of planet shows Olympus Mons also nearly on the limb, showing bright clouds surrounding the volcano. Slight atmospheric bulging also observed at mentioned location. Elysium Mons showing usual plume of bright white clouds, though not as contrasted against planet as Olympus Mons. This feature was also observed on 20 March, 1999, and has not changed perceptibly since. Cerberus showing as light albedo feature in 610 - 720 nm band, as well as in RGB frame, both in second image set. Very light haze showing in 400 - 510 nm frames over Ausonia, Xanthus, Thyle II areas.

Possible frost or arctic cloud observed on 22 April 1999, at high northern latitudes, again observed at similar location (appx 83 north latitude, 150 longitude).

Ron Zachary, Rochester Hills, Michigan, (83.05° W, 42.38° N), E-mail: rzachary@compuserve.com
Starlight Xpress MX5c; 14-inch (35 cm) f/11 Schmidt-Cassegrain telescope; Positive Projection at f/44. Color separations performed using MaxIm DL software.

07:49:01 U.T.; CM: 254°; Integration time: 0.07s
Seeing: 6-8/10; Transparency: 5/6.

David Klassen, Jim Bell, and Bill Golisch, NASA Infrared Telescope Facility, Mauna Kea, Hawaii
3.0-meter; 11:00 UT
Click on image for additional views from this observing run.

These images were taken at the NASA IRTF using the NSFCAM. Mars was imaged through the circular variable filter (CVF) at several infrared wavelengths (wavelength in micrometers listed below each image). The observations were made at about 11:00 UT by David Klassen, Jim Bell and Bill Golisch. The images have gone through preliminary processing but have yet to be absolutely calibrated.

David Klassen, Jim Bell, and Bill Golisch, NASA Infrared Telescope Facility, Mauna Kea, Hawaii
3.0-meter; 11:20 UT
Click on image for additional views from this observing run.

These images were taken at the NASA IRTF using the NSFCAM. Mars was imaged through the circular variable filter (CVF) at several infrared wavelengths (wavelength in micrometers listed below each image). The observations were made at about 11:20 UT by David Klassen, Jim Bell and Bill Golisch. The images have gone through preliminary processing but have yet to be absolutely calibrated.

Stefan Buda & Bratislav Curcic, Melbourne, Australia (5km from the city centre).
Homemade CB211 clone CCD with a mechanical shutter; 10-in. (25.4 cm) f/16 Dall-Kirkham (homemade) + 3X Barlow (effective f/50). No filters.

Seeing average (~6/10), transparency good (mag 4.5).

The interesting thing on this image pair is an apparent dark line through the Hellas region. I don't think it's an artifact as it is visible on both images (and has different aspect angle, following planet's rotation). I couldn't find such marking on any of the maps or high resolution images.

Steve Massey, Siding Springs, Australia; 149.05° E, 31.27° S; E-mail: smassey@ozemail.com.au
Astrovid 2000 CCD camera; 24-inch (61 cm) f/36 Cassegrain telescope at MSSSO.

17:10 U.T.

Victor G. Tejfel, Laboratory of Lunar and Planetary Physics, Fessenkov Astrophysical Institute, Alma-Ata, Kazakhstan; E-mail: tejf@hotmail.com
ST-6V CCD camera; 24-in (60 cm) Cassegrain.

António Cidadão, Oeiras, Portugal
ST-5C camera 10-in (25cm) f/10 Schmidt-Cassegrain

See commentary above.

25

J. Porto, Azores

Eric Roel, Mexico; E-mail: bucero@df1.telmex.netmx
Starlight Xpress interline ccd camera; 10" f/20 TEC Maksutov telescope; Negative Projection.

CM.240°. A dichroic filter with a passband of 610-720 nm.was used with an integration of .0188 second.

Images show rather clearly Mare Cimmerium; Moetis Lacus; Alcyonius Nodus; Stymphallus Lacus Propoutis and Protonilus.

Bob Bunge; E-mail: rbunge@radix.net
20-inch f/6.4 reflector, 200x and 270x.

04:45 U.T.

At 12:45, took a look to find very good seeing. Many very, very faint "dark" markings. In fact, more dark than light areas, if the very faint areas are taken into account. The faintness and softness of the detail reminded me more of drawing a 14th mag galaxy than Mars! North Polar cap harder than ever to see - very small. The larger section of Utopia just coming into view, as was the Elysium bright area and it's surrounding dark markings. In moments of good seeing, a small very dark, almost round spot appeared - apparently the very small Propoutis feature. Very faint, large dark areas around Propoutis aren't charted. Gotta wonder if a storm has stirred things up here. A bright area on the trailing (setting) edge looked like clouds - perhaps the clouds over Nix Olympica. Nice detail seen in Mare Cimmerium, including two dark, northward extensions.

Frank J. Melillo

Richard W. Wilhelm, Manorville, New York.
4.5" (11.4 cm) F/8 Newtonian.

Seeing: 7/10, transparency: 5/6.
Extensive morning and evening limb haze, accompanied by locally brighter clouds over Libya (extremely bright), Meroe Insula and Nix Olympica. Haze observed over Ausonia, prominent in green light. Elysium cloud seen (surprisingly to best advantage without filters), subtle but unmistakable. NPC bright, but not as distinct as in past observations due to what appears to be a overall brightening in the North Polar region. Hyblaeus Extension visible, along with the Propontis/Trivium Charontis group. Inability to discern the latter during my 4-22 observation probably due to reduced contrast (critical with small apertures) resulting from local afternoon clouds or haze.

Victor G. Tejfel, Laboratory of Lunar and Planetary Physics, Fessenkov Astrophysical Institute, Alma-Ata, Kazakhstan; E-mail: tejf@hotmail.com
ST-6V CCD camera; 24-in (60 cm) Cassegrain.

J. Porto, Azores

26

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

Daniel M. Troiani, ALPO Mars Section Head, Chicago, Illinois, E-mail: dantroiani@earthlink.net
17 1/2" f/4.8 Newtonian, 478x. UT

03:10-03:22
Filters: W#80a, W#47, W#25
Seeing: 4.5/10;  Transparency: 5/6
Blue Clearing (0-3): 2.5

Clouds over Tharsis region, Slight ECB visible, Solis Lacus was dark.

Mark Schmidt, Racine, Wisconsin; 88.02861° W 44.72889° N; E-mail: rasastro@wi.net
ST-5C CCD camera; 14-in (36cm) f/10 Schmidt-Cassegrain, Projection at f/31.

 L_s: 129.7°; D_e: 18.4°; Diameter: 16.1”
Seeing: #4 - #5/10; Transparency: 2-1/2 mag.

04:32 U.T. (left);	CM: 193.6°;	Integration time: 0.18s	23A & IR Rejection Filter
05:07 U.T. (right);	CM: 197.51°;	Integration time: 0.45s	Near IR 800 - 1100nm, IR Passing/Visible Rejection

Notes: Slight haze
Murnaghan Instruments Filters. Processing: CCDSoft-Image Processing Software; Skypro-Image Processing Software

Ramiro Hernandez, Saltillo, Mexico
Sony Handycam and Snappy frame grabber; 8-inch (20 cm) f/10 Scmidt-Cassegrain Meade

6:00 to 7:10 UT

Ron Zachary, Rochester Hills, Michigan, (83.05° W, 42.38° N), E-mail: rzachary@compuserve.com
Starlight Xpress MX5c; 14-inch (35 cm) f/11 Schmidt-Cassegrain telescope; Positive Projection at f/44. Color separations performed using MaxIm DL software.

07:03:47 U.T.; CM: 226°; Integration time: 0.09s
Seeing: 5-7/10; Transparency: 5/6.

	Tomio Akutsu, Japan; E-mail: is6t-akt@asahi-net.or.jp 32cm F/6.5 Reflector Telers2 KAF0400E CCD

Victor G. Tejfel, Laboratory of Lunar and Planetary Physics, Fessenkov Astrophysical Institute, Alma-Ata, Kazakhstan; E-mail: tejf@hotmail.com
ST-6V CCD camera; 24-in (60 cm) Cassegrain.

J. Porto, Azores

27

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

Donald C. Parker, Coral Gables, Florida
Lynxx PC camera, 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)     8.25-9.50s
   Green (VG9 + IR Rejection)    3.63s
   Red (RG610 + IR Rejection)   0.34s
Images flat and dark corrected.
Seeing fair (7-->5). Transparency 5m with occ clouds. Wind SE 4-9 knots, gusty. No dew.
Strong (2-3+) violet clearing. Orographics bright near pm limb. Olympus bright only after local 2pm. Elysium cloud, however, bright on am limb. Wispy clouds over Amazonis. Cerberus-Trivium only 2 dots. Dusky streak along northern borders of Sirenum and Cimmerium M. noted as in previous apparitions. Bright cloud noted in green and blue south of NPC over Lemuria -- Lemuria also bright but smaller in red.

Daniel M. Troiani, ALPO Mars Section Head, Chicago, Illinois, E-mail: dantroiani@earthlink.net
17 1/2" f/4.8 Newtonian, 478x. UT

05:40-05:58; CM: 197°;  L_s: 130.5°.
Filters: W#80a, W#47, W#25
Seeing: 5/10;  Transparency: 6/6
Blue Clearing (0-3): 2

Very bright cloubs over Southern Polar Region. Elysium slightly bright with bright following limb clouds.

David M. Moore, Pheonix, Arizona;
E-mail: davidpaulamoore@email.msn.com

J. Porto, Azores

28

Hernan Acosta, Valencia, Venezuela (10° 11.0' N, 68° 00.0' W)
4.5-inch Newtonian, 9mm Kellner, 2x Barlow
03:41 UT; CM 158°

Frank J. Melillo

Richard W. Wilhelm, Manorville, New York.
4.5" (11.4 cm) F/8 Newtonian.

Seeing: 7/10, transparency: 5/6.
Strikingly brilliant morning and evening limb haze/clouds were the highlight of this evening's observation, with the Tharsis region exhibiting particular brilliance. Southern regions of Eridania and Electris region were bright. Propoutis Complex along with the Trivium Charontis group was readily visible. The Aeolis, Zephyria and Mnemonia regions north of Mare Sirenum appeared somewhat brighter than the surrounding desert area. North polar cap was bright and distinct, exhibiting a dark surrounding rim.

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

António Cidadão, Oeiras, Portugal
ST-5C camera 10-in (25cm) f/10 Schmidt-Cassegrain

A hint of Rima Tenuis is seen in a red image (arrowed). Solis Lacus prominent, as well as the albedo marking that corresponds to the Vallis Marineris region. Clouds are seen over Amazonis, Arcadia, Nix Olympica, Tempe, Baltia, Syria, Mare Erythraeum, Cryse and Niliacus Lacus. Haze near the South Pole region? Ice (+ cloud?) near the North polar cap remains visible.

29

Nelson Falsarella, Sao Jose do Rio Preto, SP, BRAZIL; E-mail: nfalsarella@riopreto.com.br
International Mars Patrol, Rede de Astronomia Observacional, REA-Brazil
AVA ASTROVID 400 CCD Videocamera; 8-in (20cm) f/6.5 Newtonian, Eyepiece Projection with a MEADE Series 3000 Plossl 5mm.

Daniel M. Troiani, ALPO Mars Section Head, Chicago, Illinois, E-mail: dantroiani@earthlink.net
17 1/2" f/4.8 Newtonian, 478x. UT

02:48-02:58.
Filters: W#47
Blue Clearing (0-3): 2

Very large bright cloub on preceding limb.

Donald C. Parker, Coral Gables, Florida
Lynxx PC camera, 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)     8.75s
   Green (VG9 + IR Rejection)    3.63s
   Red (RG610 + IR Rejection)   0.34s
Images flat and dark corrected.
Seeing fair (4-6). Transparency 5m. No wind. Moderate dew.
Tharsis orographics bright with wispy "tails" trailing to the northwest. Elysium cloud conspicuous on am limb. Wispy clouds over Amazonis. Cerberus-Trivium only 2 dots. Dusky streak along northern borders of Sirenum and Cimmerium M. noted as in previous apparitions. Bright cloud in green and blue southwest of NPC over Lemuria -- Lemuria also bright but smaller in red.

Brian Colville, Maple Ridge Observatory, Cambray, ON Canada (79.15W, 44.28N), email:maple@quicklinks.on.ca
Pixcel 237 CCD Camera, Med Resolution - 2x2 binning, 14.8u 12-in (30cm) f/10 SCT at efr: f/40.

04:17 UT; Integration time: 0.10 sec.; Calibration: Dark, Flat; Processing: Unsharp Mask via MaximCCD.
Seeing: good, 7/10, Martian diameter 16.17", CM: 159°, Phase: .9988
Filters: IR Passing 830nm, 100nm FWHM.

Rudolf A. Hillebrecht, Bad Gandersheim, Germany
SBIG ST-5 camera, SBIG filterwheel; 7-inch f/9 Starfire Refractor, Eypiece Projection @ f/50

21:36 UT (CM: 53°, left)
22:18 UT (CM: 63°, center left)
22:43 UT (CM: 70°, center right)
23:25 UT (CM: 80°, right)

Integration Times:
   Blue (+ IR Rejection)   0.85 s
   Green (+ IR Rejection) 0.25 s
   Red (+ IR Rejection)    0.10 s
Images are flat corrected.

Seeing rather good (7/10). All RGB images are result of adding several images of each color. Processing with MaxEnt in MaximDL.
These images belong to the best resolved of Mars I have ever done. Cloudiness over Tharsis and Arcadia. Note its development during the two hours between first and last image. Limb clouds over the Ismenius Lacus area. Small and sharp North Polar Cap remnant. Voilet clearing evident.

Damian Peach, United Kingdom

30

Damian Peach, United Kingdom

Donald C. Parker, Coral Gables, Florida
Lynxx PC camera, 16-in (41cm) f/6 Newtonian, Eyepiece Projection @ f/47.8

Integration Times:
   Blue (BG12 + IR Rejection)     8.50s
   Green (VG9 + IR Rejection)    3.50s
   Red (RG610 + IR Rejection)   0.34s
Images flat and dark corrected.
Seeing fair (5-6). Transparency 5m. Wind w 0-2 knots. Moderate dew.
Tharsis orographics bright. Elysium cloud bright on morning limb. Wispy clouds over Amazonis. Cloud over Cebrenia on northwest limb. Dusky streak along northern borders of Sirenum M. and Cimmerium M. again noted. Bright cloud in green and blue southwest of NPC over Lemuria.

Bob Bunge; E-mail: rbunge@radix.net
20-inch f/6.4 reflector, 270x.

05:15 UT
Seeing: 6 out of 10.

High clouds in sky, but the moon was only two degrees or so from Mars. I suspect that glare from the Moon was reducing the contrast and impaired seeing much in the way of dark markings. However, the cloud near Nix Olympica appeared larger and brighter, with a short "tail" coming off, perhaps wind blown clouds.

Ron Zachary, Rochester Hills, Michigan, (83.05° W, 42.38° N), E-mail: rzachary@compuserve.com
Starlight Xpress MX5c; 14-inch (35 cm) f/11 Schmidt-Cassegrain telescope; Positive Projection at f/44. Color separations performed using MaxIm DL software.

07:50:44 U.T.; CM: 201°; Integration time: 0.15s
Seeing: 6-8/10; Transparency: 4/6.

	Tomio Akutsu, Japan; E-mail: is6t-akt@asahi-net.or.jp 32cm F/6.5 Reflector Telers2 KAF0400E CCD

Victor G. Tejfel, Laboratory of Lunar and Planetary Physics, Fessenkov Astrophysical Institute, Alma-Ata, Kazakhstan; E-mail: tejf@hotmail.com
ST-6V CCD camera; 24-in (60 cm) Cassegrain.

J. Porto, Azores

Marco Eckstein, Roedental, Germany, E-mail: starlight@coburg.baynet.de
Hitachi Hi8 Videocamera; 8-inch (20 cm) Schmidt-Cass. (LX-10); Eyepiece Projection with a 10mm Plossl (200x).
23:40 UT; CM 70°

Seeing: bad conditions (~3)
Albedo features not very clearly - possible dust storm in western Mare Acidalium - clouds east of Acidalium - very small polar cap

Martian Cyclone

Victor G. Tejfel, Laboratory of Lunar and Planetary Physics, Fessenkov Astrophysical Institute, Alma-Ata, Kazakhstan; E-mail: tejf@hotmail.com
ST-6V CCD camera; 24-in (60 cm) Cassegrain.

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