Tumblelog by Soup.io
Newer posts are loading.
You are at the newest post.
Click here to check if anything new just came in.

February 15 2017


Update after crash ;)

Dear Soup friends,

We had a big database crash, and the backups we had were corrupted.
The only working backup was from 2015.
We are working hard on getting some data out of the crashed database.

Please be patient!
Your Soup.io Team

Hallo Soup Freunde!

Wir hatten einen großen Datenbanken crash, und die Backups, die wir hatten waren Korrupt.
Das einzig funktionierende Backup war von 2015.
Wir arbeiten hart daran noch Daten aus der gecrashten Datenbank heraus zu bekommen.

Bitte bleibt geduldig!
Dein Soup.io Team
Reposted fromupdates updates

June 18 2015


Instrument Buch
durch Petrum Apianum erst von new beschriben.

Zum Ersten ist darinne begriffen ein newer Quadrant, dardurch Tag vnd Nacht, bey der Sonnen, Mon, vnnd andern Planeten, auch durch ettliche Gestirn, die Stunden, vnd ander nutzung, gefunden werden.
Zum Andern, wie man die höch der Thürn, vnd anderer gebew, des gleichen die weyt, brayt, vnd tieffe durch die Spigel und Instrument, messen soll.
Zum Dritten, wie man das wasser absehen oder abwegen soll, ob man das in ein Schloß oder Statt füeren möge, vnd wie man die Brünne suchen soll.
Zum Vierden, sindt drey Instrument, die mögen in der gantzen welt bey Tag vnd bey Nacht gebraucht werden: vnnd haben gar vil vnd manicherlay breüche vnd alle geschlecht der Stunden, behalten alle zu gleich ire Lateinische namen.
Zum Fünfften, wie man künstlich durch die Finger der Hände die Stund in der Nacht, on alle Instrument erkhennen soll.
Zum Letzten, ist darin ein newer Meßstab, des gleichen man nendt den Jacobsstab, dadurch auch die höch, brayt, weyt, vnd tieffe, auff newe art gefunden wirt.

Petrus Apianus: Instrument Buch. Ingolstadt 1533.
Reposted byp856astronomygroup

May 11 2015

Leonard Digges, ca. 1559: A prognostication everlastinge of right good effect (Ed. 1596, p.43).

The Linda Hall Library Digital Collections.
Reposted byastronomygroupmaardhundshallownessjalokim0earterBrzozi
William Gilbert: De mundo nostro sublunari philosophia nova, 1651.

The Linda Hall Library Digital Collections.
Reposted byastronomygroupmaardhundjalokim0
Thomas Wright: An original theory of the universe (1750), Plate XXXII.
Reposted byastronomygroup astronomygroup
Thomas Wright: An original theory of the universe (1750), Plate XXXI.

Thinking Outside the Sphere
Views of the Stars from Aristotle to Herschel

An Exhibition of Rare Books from the History of Science Collection.
Cynthia J. Rogers, Exhibition Curator.
Linda Hall Library of Science, Engineering & Technology
5109 Cherry Street, Kansas City, MO 64110.
Reposted byastronomygrouprachelinajoliescyphiphin2Dbilderkram
Leonhard Euler. Theoria Motuum Planetarum et Cometarum, 1744.
Reposted byastronomygroupphin2Dearter
Athanasius Kircher, Iter Exataticum Coeleste, 1660.

Thinking Outside the Sphere
Views of the Stars from Aristotle to Herschel

An Exhibition of Rare Books from the History of Science Collection.
Linda Hall Library of Science, Engineering & Technology
5109 Cherry Street, Kansas City, MO 64110.
Reposted byrunkensteinastronomygroupphoenix1202jalokim0Brzozi

March 02 2015


Declinations in the Almagest: accuracy, epoch, and observers
by John C. Brandt, Peter Zimmer, and Patricia B. Jones

Abstract:  Almagest declinations attributed to Timocharis, Aristyllos, Hipparchus, and Ptolemy are investigated through comparisons of the reported declinations with the declinations computed from modern positions translated to the earlier epochs. Consistent results indicate an observational accuracy of ≈ 0.1° and epochs of: Timocharis, c. 298 BC; Aristyllos, c. 256 BC, and Hipparchus, c. 128 BC.  The ≈ 42-year difference between Aristyllos and Timocharis is confirmed to be statistically significant. The declinations attributed to Ptolemy were likely two distinct groups—observations taken c. AD 57 and observations taken c. AD  128. The later observations could have been taken by Ptolemy himself.
Reposted byastronomygroupjalokim0

January 25 2015


Oldest extant magnetic compass,
from iron meteorite, pin on left side (now bent up) originally pointing North, the engraved figure demonstrates the variation of the length of days over the twelve month of the year (1st row June to January, 2nd row July to December). The object was used as a mobile sundial suspended on a string.

(1st century CE; from the Villa of the Papyri, Herculaneum, now Museo Archeologico di Napoli, Italy; catalog entry: "Object ID #335" in: http://www.ancient-astronomy.org/webapplications/gordon/SundialNavigatorProject/CurrentVersion/index.html)

[Alternative interpretation: bronze plaque to register the curing and aging of ham (bearing no relation to sundials).]
Reposted byjalokim0grubyagravaineQdeuastronomygrouphackerfleetsciencemask-and-mirrorzerocool911pleplebesenlvcksphintech

November 01 2014

The Universe (artist's impression).
(Robert Fludd: De Macrocosmi Historia, 1617)
Reposted byastronomygroupmissDot

October 21 2014

New Insights into Ancient Sundials

Larisa N. Vodolazhskaya of the Department of Space Physics at Southern Federal University (SFU), Rostov, has brought two ancient time keepers together with a new and startling result.  The story starts at the turn of the end of the 19th century with the discovery of an L-shaped bar found in the tomb of Thutmose III (1479-1425 BCE). that appeared to be a sundial. In the 1930's a "user manual" of sort was found carved on the tomb ceiling of Seti I (1290-1279 BCE) at Abydos. The ideal L-shaped bar had lines engraved with distances from a starting mark of  3, 6, 9, and 12 units. The Seti I text describes these spacings as "an established procedure".  But what is the procedure?

Then in March 2013 during the excavation of rubble associated with worker huts of Ramesses II (1279-1213) in the Valley of the Kings, Professor Dr. Susanne Bickel and her student archeological team from the University of Basel found one of the oldest sundials in the world.  It is a vertical dial of limestone with what appear to be crudely drawn hour lines. The Basel team found a poor fit using hour lines with 15° spacing expected of a traditional “unequal hour” sundial with horizontal gnomon.

Dr. Vodolazhskaya analyzes the use of these two sundial objects together, showing that the Valley of the King dial has accurately drawn hour lines that can be constructed by the L-shaped bar. The simple spacing distances of marks on the bar (ideally 1, 3, 6, 9 and 12) are measured for two L-shaped solar indicators held in the Berlin Museum.  The ratios are close to ideal, but not exact. Vodolazhskaya argues that these differences of L-shaped solar markings are intentional: one for marking (or interpreting) the morning hours of a vertical dial, and another for marking the afternoon hours where the lines are offset by half an hour. Vodolazhskaya speculates,"we associate the half-hour shift in the markup with the need for ...midday rest for workers - the traditional siesta ..."

Dr Vodolazhskaya shows that Egyptian time telling was far more advanced than previously credited, but done in such a way that only the cognoscenti, the priesthood who held the L-shaped bar, could draw the lines of a sundial to create sundials with astounding accuracy of time. Her analysis is significant, showing that the Valley of the King dial using "equal hours" implies a gnomon pointed to the north celestial pole. This Egyptian feat would not be replicated again for nearly 3000 years until the Arab Ibn al Shatir constructed the first "modern" sundial at the Great Mosque in Damascus in 1371 CE.

Read more: http://arxiv.org/ftp/arxiv/papers/1408/1408.0987.pdf
Reposted byscyphiastronomygroupLogHiMajalokim002mydafsoup-01saddam

July 31 2014

Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism
by Tony Freeth

DOI: 10.1371/journal.pone.0103275; July 30, 2014.

The ancient Greek astronomical calculating machine, known as the Antikythera Mechanism, predicted eclipses, based on the 223-lunar month Saros cycle. Eclipses are indicated on a four-turn spiral Saros Dial by glyphs, which describe type and time of eclipse and include alphabetical index letters, referring to solar eclipse inscriptions. These include Index Letter Groups, describing shared eclipse characteristics. The grouping and ordering of the index letters, the organization of the inscriptions and the eclipse times have previously been unsolved. A new reading and interpretation of data from the back plate of the Antikythera Mechanism, including the glyphs, the index letters and the eclipse inscriptions, has resulted in substantial changes to previously published work. Based on these new readings, two arithmetical models are presented here that explain the complete eclipse prediction scheme. The first model solves the glyph distribution, the grouping and anomalous ordering of the index letters and the structure of the inscriptions. It also implies the existence of lost lunar eclipse inscriptions. The second model closely matches the glyph times and explains the four-turn spiral of the Saros Dial. Together, these models imply a surprisingly early epoch for the Antikythera Mechanism. The ancient Greeks built a machine that can predict, for many years ahead, not only eclipses but also a remarkable array of their characteristics, such as directions of obscuration, magnitude, colour, angular diameter of the Moon, relationship with the Moon’s node and eclipse time. It was not entirely accurate, but it was an astonishing achievement for its era.
Reposted byylem235macounscienceastronomygroupbesenikarizatoratildevogelLogHiMaWeksschrodingersdogzupka02mydafsoup-01oscarioMrCoffepuszkaLucyLovelaceveghtibor

April 16 2014

The Moon Machine
Construction guidance by Testudinidae on http://www.instructables.com

NB: Engineers in antiquity achieved more with less gearing, see:
Reposted byidl3xh0p3ikarilunolielwujcioBat02mydafsoup-01skillzmcflymrymrumrudesiastronomygroupscience

March 29 2014

"Compass-drawn designs are among the most common of all graffiti motifs recorded in English medieval churches. Many of these are believed to have acted as ritual protection markings – to ward off the 'evil eye'. Various ancient churches in East Anglia"

March 19 2014

2612 5ce4 500
A Medieval Multiverse: Mathematical Modelling of the 13th Century Universe of Robert Grosseteste

Richard G. Bower, Tom C. B. McLeish F.R.S., Brian K. Tanner, Hannah E. Smithson, Cecilia Panti, Neil Lewis, Giles E. M. Gasper


In his treatise on light, written in about 1225, Robert Grosseteste describes a cosmological model in which the Universe is created in a big-bang like explosion and subsequent condensation. He postulates that the fundamental coupling of light and matter gives rises to the material body of the entire cosmos. Expansion is arrested when matter reaches a minimum density and subsequent emission of light from the outer region leads to compression and rarefaction of the inner bodily mass so as to create nine celestial spheres, with an imperfect residual core. In this paper we reformulate the Latin description in terms of a modern mathematical model. The equations which describe the coupling of light and matter are solved numerically, subject to initial conditions and critical criteria consistent with the text. Formation of a universe with a non-infinite number of perfected spheres is extremely sensitive to the initial conditions, the intensity of the light and the transparency of these spheres. In this “medieval multiverse”, only a small range of opacity and initial density profiles lead to a stable universe with  nine perfected spheres. As in current cosmological thinking, the existence of Grosseteste’s universe relies on a very special combination of fundamental parameters.

Reposted byscienceastronomygrouparen02mydafsoup-01

January 31 2014

Van Cleef & Arpels has a new line of expensive toys for the astronomically inclined rich...

Heliocentric mockup of an Antikythera wristwatch
... proving a dramatic decline in mechanical engineering skills since antiquity. For the original design of the Antikythera mechanism, see:

Tony Freeth and Alexander Jones: "The Cosmos in the Antikythera Mechanism" ISAW Papers 4, February 2012.

Tony Freeth: "Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism", PLOSone, July 30, 2014.
Reposted bycezarfaceastronomygroup1NdyGoleyrermstrzpleplefaulosophMezamewaitingfortheguidemiyo

January 09 2014

Fake paintings of the moon from the "Sidereus Nuncius" of "Galileo Galilei", early 21th century.

Update: Reply by Prof. Dr. Horst Bredekamp, teehee.
Reposted byastronomygroup astronomygroup

December 28 2013

Not quite the Eudoxos-Callippos model.
Reposted fromgruetze gruetze
Older posts are this way If this message doesn't go away, click anywhere on the page to continue loading posts.
Could not load more posts
Maybe Soup is currently being updated? I'll try again automatically in a few seconds...
Just a second, loading more posts...
You've reached the end.

Don't be the product, buy the product!