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Problems associated with a general scarcity of observations of the
southern sky have persisted since the present era of galactic
research began some sixty years ago. In his 1930 Halley Lecture A.
S. Eddington commented on the observational support given to J. H.
Oort's theory of galactic rotation by the stellar radial velocities
measured by Plaskett o 0 and Pearce: " . . . out of 250 stars only
4 were between 193 and 343 0 galactic longitude [=GBP1: 225 <
GBP11 < 15~; a stretch of one-third of the whole circuit was
unrepresented by a single star. This is the operation which Kapteyn
used to describe as "flying with one wing". By mathematical
dexterity the required constants of rotation have been extracted
from the lopsided data; but no mathematical dexterity can avert the
possi bility that the neglected part of the sky may spring an
unpleasant sur prise. As a spectator I watch the achievements of
our monopterous avia tors with keen enthusiasm; but I confess to a
feeling of nervousness when my turn comes to depend on this mode of
progression. " During the past few years substantial gains have
been made in securing fundamental data on the southern sky.
Interpretations based on combined southern and northern surveys are
producing a balanced descrip tion of galactic morphology. These
matters were discussed at a Workshop held at the Leiden
Observatory, August 4-6, 1982, attended by some 60 astronomers from
9 countries.
'Light on Dark Matter', held from 10-14 June 1985 in the Dutch
seaside resort of Noordwijk, was the first international conference
devoted to the results of the all-sky survey by the US-Dutch-UK
Infra-Red Astronomical Satellite (IRAS). As such, it was a hommage
to the scientists, engineers and technicians who conceived, built
and operated this extremely successful satellite. That this was
generally felt to be the case, was proven by the large number of
participants (over 200 from seventeen different nations), the li
vely discussions, and the great variety of topics presented during
the meeting. All this not withstanding a typical Dutch summer:
gale-force winds, heavy cloud cover, and meter-high surf crashing
onto a beach on which only the hardy ventur. ed. Most participants
contented themselves by watching the lonely seagulls patrolling the
North Sea coastline through the panoramic windows of the conference
center. Parallel to the IRAS Conference, a Workshop on Infrared
Properties of Interstellar Grains was organized by J. M. Greenberg
of the Leiden Laboratory Astrophysics Group: a busy shuttling of
participants between the Workshop room and the Main Conference Hall
showed that many found it hard to choose. A large number of people
were invol ved in making the Conference a success: in the first
place the scientific organizers with their valuable advice and the
conference speakers, among which I would like to mention Dr. J. H.
Around the beginning of the sixteenth century, Portuguese and Dutch
sailors first ventured into southern seas. With their keen
navigational interest in the skies, they noted the continuous
presence of two cloud-like features, not far from the almost
immediately Southern Pole. The first literature mention of these
'clouds' was in the journal written in 1520 by the Italian
navigator Pigafetta on the first circumnavigation of the globe by
Magalhaes (c/. Pigafetta et ai. , 1962). In honour of this exploit,
the objects have since become known as the Magellanic Clouds,
although the Dutch name 'Kaapsche Wolken' (Cape Clouds - after the
Cape of Good Hope) has also been in use for centuries. The Large
and Small Magellanic Clouds are dwarf irregular galaxies, orbiting
our own Milky Way Galaxy, presently at distances of 53 and 63 kpc
respectively (Humphreys, 1984) . . They are the galaxies nearest to
us: most other Local Group galaxies are of order ten times more
distant. The LMC and SMC are also the prototypical blue dwarf
irregulars, representatives of a class of objects in which several
hundred more distant objects are now known. Their masses are a few
per cent of the mass of the Milky Way Galaxy, but they are
relatively gas-rich and appear to be, at the present epoch, forming
stars at a more prodiguous rate than our Galaxy (c/. Lequeux,
1984).
Around the beginning of the sixteenth century, Portuguese and Dutch
sailors first ventured into southern seas. With their keen
navigational interest in the skies, they noted the continuous
presence of two cloud-like features, not far from the almost
immediately Southern Pole. The first literature mention of these
'clouds' was in the journal written in 1520 by the Italian
navigator Pigafetta on the first circumnavigation of the globe by
Magalhaes (c/. Pigafetta et ai. , 1962). In honour of this exploit,
the objects have since become known as the Magellanic Clouds,
although the Dutch name 'Kaapsche Wolken' (Cape Clouds - after the
Cape of Good Hope) has also been in use for centuries. The Large
and Small Magellanic Clouds are dwarf irregular galaxies, orbiting
our own Milky Way Galaxy, presently at distances of 53 and 63 kpc
respectively (Humphreys, 1984) . . They are the galaxies nearest to
us: most other Local Group galaxies are of order ten times more
distant. The LMC and SMC are also the prototypical blue dwarf
irregulars, representatives of a class of objects in which several
hundred more distant objects are now known. Their masses are a few
per cent of the mass of the Milky Way Galaxy, but they are
relatively gas-rich and appear to be, at the present epoch, forming
stars at a more prodiguous rate than our Galaxy (c/. Lequeux,
1984).
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