Category Archives: astronomy

Jericho’s tower had astronomical relevance

Astronomy was clearly important in the lives of the ancients, it seems. It was at least the case in early Neolithic Jericho, whose seemingly classless society built a stonewall dominated by which was probably the tallest building back then: a tower at least 8.25 m tall (left).

Interestingly it has been discovered now that the tower is aligned with the summer solstice in a way that, when the Sun sets that evening, the shadows of the nearby hill envelop first the tower and then the whole town.

Roy Liran and Ray Barkai, Casting a shadow on Neolithic Jericho. Antiquity, 2011. Freely accesible. 


Posted by on February 18, 2011 in astronomy, Neolithic, Palestine, West Asia


Host of Earth-like planets found

NASA’s Kepler observatory has found five planets that are Earth-like in all that is relevant: size and temperature. However the observations need to be confirmed. 
A total of 54 candidate planets were found in the habitable zones of their respective stars but most are quite larger than Earth. 
This is the result of surveying just 1/400 of the sky since February 2009, when the mission began. At about that time the “lightest exoplanet to date” was still twice the size of Earth, and not even in the habitable zone at all.
Source: Science Daily.
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Posted by on February 3, 2011 in astronomy


Video: Magdalenian astronomy (in Spanish)

This video (51’36”) is sadly only available online in Spanish language in spite of having been shot originally in English (titles) and French (language of most of the people appearing in it). It deals with the research by French astronomer Chantal Jegues-Wolkiewiez of the astronomical knowledge of ancient Paleolithic people of what is now Southern France.

[Note: an English-language copy seems to be available for purchase HERE]


Sagittarius and Scorpio?
She began her research at the Southern Alps where she discovered that the dagger symbols on a stone indicate the rise of the Sun in the Autumn equinox. Eventually she began also researching caves from the heart of Paleolithic Europe: Dordogne (near modern Bordeaux), discovering that all or nearly all the caves with paintings have a clear solar orientation, being illuminated in either an equinox or a solstice. She also found several indications that the cycles of the Moon were being recorded as well.

Most fascinating (and controversial) is anyhow her claim that the famous paints of Lascaux represent the zodiacal constellations as perceived by the ancients. This last claim is however met with scepticism by many prehistorians, even if some also sympathize with her view. Paradigm-shaking in any case. 
Note: a similar claim was staked for the paintings of not less famous Altamira cave in modern Cantabria, Spain, in the book Arqueoastronomía Hispana, which also deals with other archaeoastronomical research in the Iberian Peninsula and the Canary Islands.

The Antikythera mechanism: astonishing ancient technical and astronomical science

I do not often write on such recent historical matters but this case is really fascinating, involving not just history and archaeology but also astronomy and sophisticated mechanics that anticipate modern computers.

Jo Marchant, Ancient astronomy: Mechanical inspiration. Nature News, 2010. Open access (article).
See also: GrrlScientist’s article at Punctuated Equilibrium blog at The Guardian: The Antikythera Mechanism. This is what I want for Christmas! 
This last article (found via Archaeology in Europe), features a fancy video of a Lego reconstruction of the mechanism (which is pretty curious indeed) but more interesting are maybe the following two videos from Nature YouTube channel:
It is lovely, I understand, to see how these ancient peoples had such a complex understanding of Astronomy, being able to predict eclipses with high detail. But maybe even more fascinating is that they were already building elaborate clock mechanisms for that purpose, devices not known to have existed otherwise until the eve of Modern Age. 
In the last video it is suggested that the astro-clock could have been invented by Archimedes of Syracuse, whom we know was the most celebrated scientific genius of Antiquity. The geography suggested by the mechanism is one of the Ionian Sea, not the Aegean or the East Mediterranean, however the date is from a century after Archimedes died. Yet they ponder if there could have been an Archimedean school in Syracuse for some time, which was in fact producing these technological marvels, whose knowledge was later lost. 
It is also impressive to realize how technology may be lost, maybe because of lack of demand or socio-cultural drive. Ancient Greeks also knew of other marvels such as rudimentary steam engines, which never had much of an impact in that society overall – yet they would change everything two millennia later.

Mars water is recent

Deposits of soluble minerals under the wheels of the trapped Mars rover but not in the upper layer support that water existed in liquid form recently on the red planet, otherwise the layers should be mixed by wind erosion.

Full story at Science Daily.


Posted by on October 29, 2010 in astronomy, Mars, water


Some news to heat this up

From Science Daily. None too interesting to write a whole post, in my humble opinion but interesting enough to mention.
Clovis points
Clovis impact not needed to explain the end of Clovis culture. People may have changed habits… Read more…
Rare disease gene may help explain human phenotype diversity. Read more…
Rate of new species declining, before humans arrived. Why? Read more…
West Nile Virus mosquito has more genes with smaller genome. Read more…
Heliosphere much more variable through time than expected. Why? Read more…