TYCHO

43.3S by 11.2W

LUNAR TRANSIENT PHENOMENA

HISTORY

DAVID O. DARLING

"Tycho is a well-formed crater in the southern uplands, 54 miles across, with high terraced walls and a central mountain complex. Magnificent though it is, Tycho lies in so crowded an area that it would not be outstanding were it not for the rays. When it first emerges from the long lunar night it seems to be a perfectly normal bright crater, but gradually the rays come into view, until full moon they dominate the whole of the southern part of the disk. There are dozens of them, streaking out in all directions from Tycho as a focal point; they cross craters, plains, peaks and valleys, uplands and maria, rills and pits without showing obvious deviation.

Near full moon, when Tycho's rays dominate the whole scene, it is tempting to believe that the crater lies at the lunar pole. In fact it does not; It is some way away.

Rather unexpectedly, the rays cannot be traced inside Tycho itself. There is a ray free area round the rampart, showing darkish under a high light, where the streaks stop short; neither do they radiate from the exact centre of Tycho, since many of them are tangential to the walls. Yet there can be no doubt that the rays were produced at the time of impact which formed the crater-and since the rays cross all other formations this is proof positive that Tycho must be the youngest structure in this part of the Moon. One ray stretches right beyond the Mare Serenitatis, passing close to the bright little crater Bessel, and there has been a great deal of discussion as to whether this is one long, genuine 'Tycho ray' or whether it has been renewed along its course - though it is not easy to see just how this happened. In January 1968 the Surveyor 7 space-craft made a gentle touch-down on the outer slopes of Tycho, and sent back excellent pictures. It is still there, and one day no doubt, it will be collected and taken away to a lunar museum." Patrick Moore On the Moon January 2001.

Photograph taken by Lunar Orbiter 5 space craft of the crater Tycho, north is to the top and east to the right.

Lunar Orbiter 5 Photograph 5L0 125M (N.A.S.A)

Close up view of the central peak complex inside the crater Tycho. During the last twenty years I have witnessed numerous strange appearances of the central peak. Looking like a comet nucleus with a star in the center of the cloud, this star will wink in and out slowly and after several minutes will disappear. I have also documented strange arches of light crossing the crater floor while it still deep in shadow. I was also succeeded by capturing on video a wish bone shaped glow extending from the central peak to the eastern wall. You can learn more about these observations by going to L.T.P. Reports on the left column and then clicking on the Tycho reports.

Clementine Photograph (N.A.S.A.)

The three color images below show Tycho in different wave lengths to allow for identification of different rock types found inside the crater. At present I have found no match to the shapes of the illumination observed and to the different rock types found on the crater floor. This examination was done going on the premise that light may be reflecting off the crater rim illuminating shadow filled crater floor.

Clementine Photograph (N.A.S.A.)

"Three mosaics of the same scene over the crater Tycho (43°S, 11°W; 85 kilometers in diameter). On the right is a “stretched” color mosaic of the crater, exaggerating the relatively blue reflectance of the central peak. The false, multicolor version (center) further exaggerates these color contrasts and allows different color (rock) units to be distinguished. The simple ratio image (left) shows the location of fresh, “mafic” material (i.e., materials relatively rich in iron and magnesium). Such color data from Clementine permit lunar scientists to map rock types over the entire surface of the Moon."

Image processing by U.S. Geological Survey, Flagstaff, Arizona.

The photograph below shows the Surveyor 3 spacecraft which landed in the Ocean of Storms, this space craft was identical to Surveyor 7. You can see in the background the Lunar Excursion Module (L.E.M.) Intrepid. The astronaut inspecting the Surveyor space craft is Pete Conrad.

Apollo 12 mission photograph of Surveyor 3 space craft (N.A.S.A.)

The photograph below was a mosaic put together of the landing site looking north. This space craft also provided the best documentation of horizon glow. To examine these photographs click here. Since the Moon has no atmosphere there should not be any lingering glows in the sky after the Sun has set. It has been suggested that what Surveyor 7 photographed was dust levitation rising up from the lunar surface due to positive and negative charges across the boundary line between day and night.

Surveyor 7 photographic mosaic of landing area on north rampart of Tycho. (N.A.S.A.)

The total number of lunar transient phenomena events for this crater listed in Lunar Transient Phenomena Catalog (Cameron, 1978). is twelve. The following is a listing of these anomalous appearance of the crater Tycho..

10/04/1884 - Tycho appeared like a second magnitude star during a lunar eclipse.

01/08//1898 - During mid-lunar eclipse the Earth's shadow was so dense details of lunar surface disappeared except for the bright ray extending SSW from Tycho, which was clearly visible. It's unusual for that ray to remain visible when the ones toward Kepler and Aristarchus are not.

04/11/1903 - Tycho rays remain visible in the Earth's shadow for 30 minutes until the Moon reached mid-eclipse.

08/15/1905 - Tycho was visible, even brilliant, in Earth's shadow during lunar eclipse.

04/01/1912 - Tycho was visible as a bright spot standing out in the slate-gray Earth's shadow. No other formations were visible during eclipse.

11/07/1919 - Tycho's long ray in the direction of Longomontanus remained visible as a weak gray-green light throughout the lunar eclipse.

03/27/1931 - Tycho's central peak shadow appeared a curious gray shade even though the interior was in shadow.

07/14/1940 - Shadow in Tycho appeared irregular in shape, with ragged margin, and had luminous marks in it. The east wall of Tycho had a milky luminosity.

12/09/1940 - Tycho had luminosity visible on the west rim of its outer slope.

11/17-18/1956 - The craters Tycho, Aristarchus, Proclus, Manilius, Byrgius, and Kepler appeared extraordinarily bright.

04/15/1970 - Tycho had a slightly pulsating white glow on its western (IAU?) external wall.

07/24/1975 - Copernicus and Tycho were both indistinct in red and blue filters. Fracastorius had a positive blink in red or blue filter.

Research being conducted by using infrared photography has provided new insight into the thermal dynamics of the Moon during lunar eclipses. To learn more about this click here.

The L.T.P. plotting by age of the Moon shows a very limited levels of activity. The sun rises on Tycho is between the 8th and 9th day. This is when the first activity been reported. No activity reported during sunset period which is unusual since this is when I have witnessed four separate L.T.P. events taking place. When you read the summary of events listed above, six of these took place during a lunar eclipse. I will have listed a complete account of my four observations on this web site in the near future..

The plotting by months of the year do not give any significant time of the year that more events are reported.

This graph below shows that out of all the lunar transient phenomena reported the brightening event is most dominate, with gaseous following. This number includes the 6 events that took place during lunar eclipses when Tycho was glowing brightly in the umbra shadow..

The drawing below was done from a b&w video which allowed me to capture the fine detail that not possible when sitting at the eyepiece. You can do still frame and freeze the image at the best moment of best seeing.

Conclusion: The crater Tycho is not high in number when it comes to lunar transient phenomena catalog. But what phenomena that been recorded has been extremely interesting. My own observations of lunar transient phenomena in this crater has sent me on a thirteen year odyssey in an attempt to discover what mechanism is responsible. I have done numerous follow up observations when the lighting conditions and the colongitude were similar. Documenting these observing sessions with video, still camera, and CCD images. Also I have coordinated observers from around the world to conduct continuous monitoring of this crater to gather long term data on its behavior during the sunrise and sunset. I have also done extensive monitoring of this crater during lunar eclipses, imaging and video taping Tycho as it passes through the umbra shadow. During a number of lunar eclipses I conducted infrared photography specifically to monitor the crater Tycho while it was in the umbra shadow. The results of all these observations will be posted on this web page as soon as time permits.