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Catena Davy from Apollo 12 spacecraft k tV "^MisEnHSH

Davy and Catena Davy 2004.09.05 -20:12 LIT Age 21 days. 10-in f/6 Newtonian + 5X + Tollcam [150% msized)

In T093, a dome is recognized outside the rim of Davy. Six lAU-named craters are marked along the eastern section of Catena Davy:

Davy and Catena Davy 2004.09.05 -20:12 LIT Age 21 days. 10-in f/6 Newtonian + 5X + Tollcam [150% msized)

In T093, a dome is recognized outside the rim of Davy. Six lAU-named craters are marked along the eastern section of Catena Davy:

Harold (6.0PW 10.9PS 2 km) Delia (6.10W 10.9°S 2 km)

Alan (6.10W 10.90S 2 km) Priscilla (6.2°W 10.9PS 1.8 km)

Osman (6.20W 11.00S 2 km) Susan (6.30W 11.00S 1 km).

Other chains of craterlets are found close to Deslandres, Ptolemaeus, Rima Hyginus, Timocharis, Aristóteles, Eratosthenes, Montes Carpatus, Euler, Maestlin, Krafft, Vitello and Stofler. They are marked by arrows in the guide maps below. Most of them are nameless.

C h a i n Of C rater I ets (Refer to the Map No. for full picture.)

C h a i n Of C rater I ets (Refer to the Map No. for full picture.)

Davy Crater Chain Nasa
T173 shows a gourd-like crater array composed of Vogel, its satellite craters A, B and C. Vogel can be spotted with the larger map in next page. It is 26 km in diameter.
Vogel and its satelfite Craters 2004.09.05 20:27 UT Age 21 days. 10-inK + 5X + TbUcam

T071 shows a row of diminishing craters, composed of Halley, Hind, Hipparchus C and Hipparchus L. Hipparchus is a vast walled plain, 138 km in diameter, Map 12. Its walls are modified by a pattern of grooves and ridges known as "Imbrium Sculpture". This pattern is radial to Mare Imbrium, which affects the lunar surface for more than 1000 km from Imbrium. The same pattern can be seen in the middle of T173. Horrocks (30 km) is a younger crater within Hipparchus. Pickering (15 km) is named after E. C. Pickering, the former director of Harvard College Observatory. [Remark: Messier A of \Map 6 was once named as Pickering (after W. H. Pickering, the smaller brother of E. C. Pickering), but this W. H. Pickering was removed from crater nomenclature since 1964.]

Pickering Lunar Crater
Hipparchus & vicinity 2004.0E.25 12:47 UT Age 0days. 10-inf/G Newtonian + 2.5X + ToUcam. 6 framesStacked.

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Delaunay, la Caille E and la Caille M form a bell-shaped crater array. Delaunay is 46 km in diameter. Its floor is divided by a sharp central ridge.

2004.12.19 12:41UT Age 7 days. 10-in fl6+2.5X+ToUcam The * was crater Waiter, row renamed as Waltfier.

l MMm

Delaunay, la Caille E and la Caille M form a bell-shaped crater array. Delaunay is 46 km in diameter. Its floor is divided by a sharp central ridge.

2004.12.19 12:41UT Age 7 days. 10-in fl6+2.5X+ToUcam The * was crater Waiter, row renamed as Waltfier.

Domes

Domes refer to small, rounded low elevation found mostly on lunar maria. They swell up from ground level to slope 10 ~ 50 and are believed to form during the later stages of lunar volcanism, when the rate of lava extrusion had decreased. Lunar domes are similar to the shield volcanoes on Earth. Sometimes they have calderas, visible as summit pits or craterlets in telescopes. However the megadome, which is a large uplifted piece of the crust (diameter more than 30 km), is more complex in nature. Lunar domes and megadomes located near a known feature are highlighted in the following maps; they require very oblique sunlight to be seen.

Examples of lunar volcanic domes

Examples of lunar volcanic domes

Shield volcano Darwin on Isabella Island In Pacific Ooean, It has an exceptionally large summit caldera, día. 5 km, height 1330 m. (Image made from radar dala 4 elevation data)

6. Coper nicus, Hortensius & Milichius, |Map19|.

9. Gruithuisen, Mairan T & Mons Rümker, |Map 22|.

14. Sinus Iridum, |Map18.

15. Aristarchus & Herodotus, |Map 21|.

18. Valentine Dome (megadome), |Map15|. Other megadomes are shown in next page.

More details:

http://www.Qlrgroup.org/news/28.htm, http://digilander.libero.it/glrgroup/

Megadome is a near-circular plateau or uplift piece (usually on lunar mare) which has diameter more than 30 km and low elevation of few hundred meters. The plateau surface is textured with protrusions, depressions, ridges, rilles, craterlets etc. The large diameter means it is within the reach of small telescopes. But the trick is that all megadomes are truly low in height and poor in contrast, so they are noticeable only under very oblique sunlight. The nature of megadomes is complicated and not fully understood, though hints suggest that they are volcanic. (Reference: http://www.lpi.usra.edu/meetinqs/lpsc2005/pdf/11I6.pdf)

Megadomes on the nearside of the Moon (low elevated plateaus, size greater than 30 km) Aristarchius Plateau is 60% resized. Refer to the Map No. for full picture.

Lunar Rays

When the Sun illumination angle is high enough (e.g. 300 or more), bright rays begin to emit from certain craters. The table below lists those craters known to have bright rays.

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