R. Lena, G. Santacana, KC Paul,  A. Maffioli, F. Badalotti, Pg. Salimbeni, M. Higashida, R. Porta, G. Venturin.

In previous paper we studied the geologic units and domes  in western Mare Tranquillitatis near the crater Arago.

The Badalotti's frame showed the features located on the top of the two large domes called Arago alpha and beta.

 On  the other hand there is an extensive system of wrinkle ridges associated with the Lamont. Lamont is a ghost crater.

As visible in the images obtained by Maffioli and Venturin the albedo of Lamont is higher of the albedo near Arago. The difference is due to the presence of different basalts.

 This region  is  a difficult but interesting area to study. Several observers reported  the big 20 km dome just to the north of Arago. This seems to be an irregularly shaped dome with a small surface feature in its south end. It seems to be a small crater. The surface of the dome seems rough at high magnification (as at 444x).
 

 G. Santacana Arago Domes on 10 april 2000-                                       Time: 01:34 UT  Telescope: 8" SCT at 444x .                                   Seeing: 6  Transparency: 5 (ALPO scale)

The pit observed by Santacana was also confirmed by lena and Cicognani. An interesting image was obtained by Badalotti. There is a strong correlation between Santacana's drawing and Badalotti's frame.
The pic.   below show the dome arago alpha  (orientation with south on the bottom)
 
 

Francesco Badalotti - July, 3, 1999 at 23,45 UT. Frame obtained using a video camera SCT 25 cms f/10.
The other four domes lie almost in line a bit to the northwest of Arago. These are high profile domes about 8-10 km in diameter. Arago beta was observed too. It is a large structure of about 13 Km of diameter. Visual estimations were obtained by Santacana and Lena. These domes appear in the lunar  atlas.

The Arago domes observed during a program performed by GLR group were:

Paul kc -Arago Domes:  on 10 december  2002 19:32 UT - Image taken with CN212 + 2x barlow + Philips Toucam Pro
 

 R. Porta drawing carried out on   8 June, 2000 at 19-19:40 UT
Seeing   II (Antoniadi scale)  SCT 200mms  f/10 ( 222x and 250x yellow filter W 8 ). Several ridges to the east and west of Arago.
 
 

R. Lena : on 10 november 2002 18:00 UT refractor 10 cm f/15 250 x.

 Maffioli A. -Arago Domes:  on 8 june 2000 SCT 8" (seven  frame) frame obtained using   videocamera

G. Venturin on 12 march 2000 at 21:15 UT. Photo acquired on Fuji Reala 100 with 1 sec. at f/40 (plossl 16 mm) . Refractor apo 130 mms.
 

 Santacana reported, during the observation carried out on 10 april 2000,  the presence of the small dome like structure to the south east of Arago. Although not in the drawing, a small 4km dome
was observed at the point where the upper ray from the crater ends by Santacana. This dome was recorded  by  Higashida and it is a small structure well defined reported in the ALPO list.
 

 M. Higashida- CCD image of the Arago region (Newton 200 mms f/6)
In boxed area (xi 0.368 and eta 0.096) is located a dome of 3.9 km of  diameter

The boxed area shows the dome. The dome was measured from the frame and the data showed the dimension  of 3.9 Km.
It is located at xi 0.368 and eta 0.096 corresponding to ALPO referements.

It translate to long 21.70° and lat 5.51° using the software Tools ALPO by H.D. Jamieson.

We recommend more study of this area specially under low illumination
angles.
 

Send your observations to the GLR group.