Historical moments in solar observation
Day 1 - And God said, Let there be light...and there was light...
968 - First mention of the solar corona:
"...at the fourth hour of the day ... darkness covered the earth and all the brightest stars shone forth. And is was possible to see the disk of the Sun, dull and unlit, and a dim and feeble glow like a narrow band shining in a circle around the edge of the disk".
1128 - First recorded sketch, by John Worcester!
“In the third year of Lothar, emperor of the Romans, in the
twenty-eighth year of King Henry of the English … on Saturday,
8 December, there appeared from the morning right up to the
evening two black spheres against the sun.”
John of Worcester, recording the event in his Chronicle of the year
December 8, 1128, clearly found the sight memorable, and perhaps ominous. The
Latin script surrounds a colour diagram of the Sun, marking the
position and size of the two sunspots he had seen with the naked eye
– this was five centuries before the invention of the telescope!
December 13, 1128 - 5 days later in Korea!
On the night of 13 December 1128, astronomers in Songdo (the modern
city of Kaesong), Korea, witnessed a red vapour that “soared and filled
the sky” from the north-west to the south-west. Their observations, of
a rare southern manifestation of the aurora, were recorded in the Koryo-sa,
the official Korean chronicle of the period, with precise calendrical
information determining the date.
For modern astronomers, the accounts have a striking concurrence,
confirming the accuracy of the two chronicles, and providing evidence
of unusual solar activity in this period of the twelfth century. Sunspots,
and the geomagnetic storms which cause auroral displays, are related
effects of active solar regions. A delay of five days is typical of the
average delay between the occurrence of a large sunspot group near the
centre of the Sun’s face – exactly as witnessed by John of Worcester –
and the subsequent appearance of the aurora borealis in the night sky at
relatively low latitudes.
1613 - One of Galileo's sketches!
In 1612 during the summer months, Galileo made a series of sunspot
observations which were published in Istoria e Dimostrazioni Intorno
Alle Macchie Solari e Loro Accidenti Rome (History and Demonstrations
Concerning Sunspots and their Properties, published 1613). Because
these observations were made at appoximately the same time of day,
the motion of the spots across the Sun can easily be seen.
1801 - Reproduction of William Herschel's original diagram on the nature of sunspots!
This hypothesis relies heavily on the asymmetric appearance of
sunspots when seen near the solar limbs, as originally pointed
out by A. Wilson in 1774. The physical nature of sunspots remained
a topic of controversy for nearly three centuries. The universally
opinionated Galileo proposed, with unusual reservation, that
sunspots may perhaps be cloud-like structures in the solar
atmosphere. Scheiner believed them to be dense objects embedded
in the Sun's luminous atmosphere. In the late eighteenth century
William Herschel (discoverer of the planet Uranus), following an
hypothesis earlier put forth by A. Wilson in 1774, suggesting
that sunspots were opening in the Sun's luminous atmosphere,
allowing a view of the underlying, cooler surface of the Sun
(likely inhabited, in Herschel's then influential opinion).
1845 - First solar image, by Louis Fizeau!
The first surviving daguerrotype photograph of the sun was taken
at the dawn of photography in 1845 by French physicists Louis Fizeau
and Lion Foucault. The 5-inch image showed many details including a few sunspots.
1859 - First solar flare sketched, by Richard Carrington!
On 1 September 1859, the amateur astronomer Richard C. Carrington
was engaged in his daily monitoring of sunspots, when he noticed
two rapidly brightening patches of light near the middle of a
sunspot group he was studying (indicated by A and B on the drawing
above). In the following minutes the patches dimmed again while
moving with respect to the active region, finally disappearing at
positions C and D. This unusual event was also independently
observed by R. Hodgson, another British astronomer.
1860 - The total solar eclipse of 18 July 1860 was probably the
most thoroughly observed eclipse up to that time. The three
drawings are a sample of drawings produced at that time which
include depictions of a peculiar feature in the
SW (lower right) portion of the corona. Based on comparison
with modern coronal observations, it is quite likely that
these represent the first record of a Coronal Mass Ejection in progress!
E.W. Murray
G. Tempel
Franz Von Feilitzsch
1919 - A diagram illustrating Hale's Polarity Laws!
A diagram taken from the 1919 paper by G.E. Hale, F. Ellerman,
S.B. Nicholson, and A.H. Joy (in The Astrophysical Journal, vol. 49,
pps. 153-178), illustrating what is now known as Hale's polarity laws.
This presented solid evidence for the existence of a well-organized
large-scale magnetic field in the solar interior, which cyclically
changes polarity approximately every 11 years.
In the decade following his groundbreaking discovery of sunspot magnetic
fields, George Ellery Hale (1868-1938) and his collaborators went on to
show that large sunspots pairs almost always (1) show the same magnetic
polarity pattern in each solar hemisphere, (2) show opposite polarity
patterns between the North and South solar hemispheres, and (3) these
polarity patterns are reversed from one sunspot cycle to the next,
indicating that the physical magnetic cycle has a period of twice the
sunspot cycle period. These empirical observations have stood the test
of time and are since known as Hale's polarity Laws. Their physical origin
is now now known to originate with the operation of a large scale hydromagnetic
dynamo within the solar interior, although the details of the process are far
from adequately understood. Because the sun's dynamo generated magnetic field
is ultimately responsible for all manifestations of solar activity (flares,
coronal mass ejections, etc.), to this day solar dynamo modeling remains a very
active area of research in solar physics.
December 2, 1995 - SOHO(SOLAR AND HELIOSPHERIC OBSERVATORY) was launched!
SOHO, the Solar & Heliospheric Observatory, is a project of international
collaboration between ESA and NASA to study the Sun from its deep core to
the outer corona and the solar wind. Here is one of SOHO's images:
September 23, 2006 - HINODE(SOLAR B) was launched!
Solar-B's overall goals are to understand how energy generated by magnetic-field
changes in the lower solar atmosphere (photosphere) is transmitted to the upper
solar atmosphere (corona), to understand how that energy influences the dynamics
and structure of that upper atmosphere, and to determine how the energy transfer
and atmospheric dynamics affects the interplanetary-space environment. . Here is one of HINODE's images:
March 6, 2007 - I begin my solar observations!
Here is one of my first sketches from March 9th, 2007, I didn't notice how much
it looked like the very first known sketch until I made this site:
