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The SOCIETY for POPULAR ASTRONOMY
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Electronic News Bulletin No. 183 2005 October 2
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Here is the latest round-up of news from the Society for Popular
Astronomy. The SPA is Britain's liveliest astronomical society, with
members all over the world. We accept subscription payments online at
our secure site and can take credit and debit cards. You can join or
renew via a secure server or just see how much we have to offer by
visiting http://popastro.c.topica.com/maad3w3abkQC8ciD1pRb/

Philip's, a publisher of astronomy books and planispheres for the
amateur astronomer, is sponsoring this bulletin. For information on
certain Philip's titles see the end of this bulletin.


METEOR PROSPECTS FOR OCTOBER
By Alastair McBeath, SPA Meteor Section Director

A month of possibilities is forthcoming, though the major Orionids lose
out to the bright Moon.

Checking for any Draconid activity is favourable this year, as the waxing
crescent Moon sets by mid-evening on October 8-9, the most likely time
for any such meteors to happen. Previous Draconid returns - rarely up to
storm levels - have tended to prefer years when their parent comet,
21P/Giacobini-Zinner, was at perihelion, and was still fairly close to the
Earth by early October, as last in 1998, when a strong outburst occurred
over the Far East, and Zenithal Hourly Rates, ZHRs, reached ~700 briefly.
The comet was at perihelion most recently on July 2 this year. Past
evidence suggests this is probably too distant to still create detectable
shower activity this autumn, and nothing has been predicted, but an
unexpected minor outburst happened over Japan in 1999, showing there
are unknown features to watch out for with this source. If anything takes
place, it may well fall between 15h UT on October 8 to 01h UT on
October 9. The radiant is by Draco's "mouth", circumpolar from the UK,
but highest in the early evenings and early mornings. Draconids are very
slow meteors.

After mid-month, the waning gibbous Moon passes a few degrees north
of the Orionid radiant, with perfect timing for the shower's maximum on
October 21. Observing will thus be about as unfavourable as it can be, as
by the time the radiant is usefully observable then, after ~23h UT for
Britain, the Moon will be well up and ruining the sky! ZHRs should be
about 20 at best this year, rising towards their next possibly cyclical rates-
peak (highest ZHRs circa 30), around 2008-2010, following a 12-year
periodicity if the latest International Meteor Organization research proves
correct. A strong sub-peak, with ZHRs similar to the main maximum, is
possible on October 17-18, though it has been reported from only two
years so far, 1993 and 1998. Full Moon on October 17 spoils that very
neatly. However, Orionids are fast, often bright, and frequently trained,
and some should still survive the moonlight. Anyone with clear skies and
hoping to view at least a few shower meteors well after midnight around
October 21, should watch as much sky as possible, looking well away
from the Moon.

The last week of October may bring a recurrence of the Taurid 'swarm',
a region of more and somewhat larger Taurid meteoroids than normal
thought to lie within the main Taurid meteoroid stream, a concept
proposed by professional meteor astronomer David Asher at Armagh.
Previous 'swarm' return-years predicted by him have produced more
bright Taurids than normal, including some notable fireballs (in 1995,
lasting roughly from late October to mid November), and ZHRs of 8-10
(similar to what is seen during their typical November maximum spell)
around 1998 October 27-31. David has suggested 2005 could see
another autumnal Taurid 'swarm' return.

Uncertainties in the nature of this possible 'swarm' mean exact predictions
cannot be made yet about what may happen or when, but various
investigations suggest if anything takes place at all, it is most likely
between October 20 and November 15. The Moon is at last quarter on
October 25, and new on November 2 early in this spell. The Taurid
radiants are a pair of large, ill-defined areas around Aries, Cetus and
extreme western Taurus by late October, which can be observed properly
by about 21h-22h UT from the UK. Watchers should thus take
advantage of any moonless, clear skies that manifest from October 25 or
so onwards. Be warned though that even enhanced Taurid rates may not
be easily detectable, unless we are extremely lucky and the showers again
produce a good crop of fireballs. The 1998 enhancement was first found
by a careful analysis of the global radio data, and only later confirmed
from a detailed examination of the visual records. None of the individual
observers - radio or visual - had been aware the shower had behaved
differently to normal from their own data alone.

More details on October's meteor activity, plus what to report of your
observations and where to, can be found off the SPA Meteor homepage
at: http://popastro.c.topica.com/maad3w3abkQC9ciD1pRb/


NASA'S SPACECRAFT PLANS
NASA

NASA has published plans for the next generation of spacecraft to take
people back to the Moon and on to Mars and other destinations. The
study makes specific design recommendations for a vehicle to carry
crews into space, a family of launch vehicles to take them to the Moon
and beyond, and a 'lunar mission architecture' for landing on the
Moon. It also recommends the technologies that NASA should pursue in
the near term. The study will assist NASA in achieving President
Bush's 'vision for space exploration', which calls for the agency to
return the space shuttle to safe flight, complete the International
Space Station, return to the Moon, and continue exploration to Mars
and beyond.

America's next-generation spacecraft will use an improved, blunt-body
crew capsule, and will accommodate up to six people. The spacecraft
will be built upon the foundation of the proven designs and
technologies used in the Apollo and space-shuttle programmes, while
having far greater capability. It will be able to carry larger and
heavier cargoes into space and allow more people to stay on the Moon
for longer periods of time. The new spacecraft will be able to be
configured either to support human explorers or fly unpiloted to carry
cargo. Its design allows the flexibility to ferry crews of three
astronauts, plus additional supplies, to and from the International
Space Station, take four crew members to lunar orbit, and eventually
maintain up to six astronauts on a mission to Mars. Crews and cargo
will be carried into orbit by a launcher consisting of a
solid-propellant booster and an upper stage powered by a Shuttle main
engine that can lift 25 metric tons. The spacecraft is intended to be
safer than the space shuttle because of its in-line design and
launch-abort system.


CASSINI RADAR SHOWS SHORELINE ON TITAN
NASA

Images returned during Cassini's recent fly-by of Titan show evidence
of what appears to be a shoreline cutting across the southern
hemisphere, dividing a distinct bright and dark region roughly 1,700
kilometres long by 170 kilometres wide. Next to an area that is
bright and possibly rough is one that is very dark and smooth.
Patterns in the dark area indicate that it may once have been flooded
with liquid that may now have partially receded. Bay-like features
also lead scientists to speculate that the bright--dark boundary is
most likely a shoreline.


RING OF STARS AT ANDROMEDA'S HEART
New Scientist

The Andromeda galaxy is thought to have at its core a super-massive
black hole that the Hubble telescope now finds to be surrounded by a
disc of young stars. The newly discovered disc is composed of over
400 very hot, young blue stars, orbiting like a planetary system very
close to the black hole. That puzzles astronomers because the black
hole's intense gravitational field should have torn apart any clouds
of matter long before they could coalesce to form new stars. The
stars form a very flat disc that is only one light-year across. An
elliptical disc of older red stars surrounds it, spanning about five
light-years. Since the two discs appear to be in the same plane, they
are probably related, but no one understands how either disc came into
being. Spectroscopic observations made by Hubble suggest that the
disc of blue stars is only about 200 million years old, while the
galaxy itself is far older. They also allowed astronomers to
determine the movement of the blue stars and thereby estimate the
black hole's mass. It really IS super-massive, with a mass 140
million times that of our Sun.


MARS PROBE GETS MISSION EXTENSION
ESA

The Mars Express spacecraft which has been orbiting Mars since 2003
has been granted a mission extension of one Martian year (nearly two
Earth years). Mars Express has helped to give us a more complete view
of the planet, including evidence for atmospheric methane, a frozen
sea and 'geo'logical activity. But one of its instruments may now
have stopped working, and deployment of its radar was delayed for a
year. The Marsis (Mars Advanced Radar for Subsurface and Ionosphere
Sounding) was finally deployed in the middle of this year after fears
that one or both of its 20m-long booms might hit the spacecraft after
opening out. The mission extension should allow Marsis to re-start
its search for water reservoirs beneath the planet's surface. Other
instruments have been measuring the composition and characteristics of
the Martian surface and atmosphere, and have suggested that volcanic
and glacial processes have occurred much more recently than had been
supposed.


LARGE POPULATION OF GALAXIES FOUND
ESO

A team of astronomers using the VLT has discovered a large population
of distant galaxies observed when the Universe was only 10 to 30 per
cent of its present age. A total sample of about 8,000 galaxies
selected only on the basis of their observed brightness in red light
was found to include almost 1,000 bright and vigorously star-forming
galaxies that were formed between 9 and 12 billion years ago,i.e.
about 1,500 to 4,500 million years after the Big Bang. The galaxies
had been missed because previous surveys had selected objects in a
much more restrictive manner. While observations and models had
previously indicated that the Universe had not yet formed many stars
in the first billion years of cosmic time, the discovery calls for a
significant revision, since it now seems that stars formed two to
three times more quickly than some astronomers had thought.


ESA MISSION AIMS FOR ORBITAL DEFLECTION
The Register

The European Space Agency is planning a mission to see how well
current technology could deal with the threat of an asteroid impact.
For a rehearsal deflection mission, dubbed Don Quixote, the agency has
selected asteroids 2002 AT4 and (10302) 1989 ML as possible mission
targets, but the final decision will be made when the launch date has
been fixed. The mission will see two spacecraft travel to the chosen
asteroid. The first, called Sancho, will arrive several months in
advance of the second, Hidalgo. When Hidalgo arrives to smash into
the asteroid, Sancho will be there to observe any changes to the
asteroid's orbit.


GIANT GALAXIES IN NEWBORN UNIVERSE
NASA

Astronomers have discovered that one of the most distant galaxies ever
seen is unusually massive and mature. The galaxy, named HUDF-JD2,
appears to have built up amazingly quickly, within the first few
hundred million years after the Big Bang. It put about eight times
more mass into stars than there is in our own Milky Way today, and
then, just as suddenly, it stopped forming new stars. The galaxy was
identified among approximately 10,000 others in a small patch of sky
called the Hubble Ultra Deep Field. It represents an era when the
Universe was only 800 million years old, about five per cent of its
present age. Scientists studying the Ultra Deep Field found the
galaxy in Hubble's infrared images. They expected it to be young and
small, like other known galaxies at similar distances. Instead, they
found evidence that the galaxy is remarkably mature and much more
massive. Its stars appear to have been in place for a long time.
Moreover the galaxy looks even brighter in longer-wavelength infrared
images from the Spitzer space telescope. Spitzer is sensitive to the
light from older, redder stars, which should make up most of the mass
in a galaxy. The infrared brightness of the galaxy suggests that it
was already comparable in mass to present-day large galaxies.


PHILIP'S NEW TITLES:

Published last month: a brand-new, fully revised edition of Sir
Patrick Moore's Atlas of the Universe, updated to include new images
from the Cassini spacecraft and Huygens probe, the Hubble Space
Telescope, the Very Large Telescope and Mars Express. £25.00.

Philip's Astronomy Dictionary has been completely updated to include
more than 1000 A--Z entries, which cover the stars and planets,
galaxies and cosmology, amateur astronomy and professional
observatories, space exploration, famous astronomers, scientific
terms, theories and much more. £9.99.

New this month: the 4th edition of Philip's Pocket Star Atlas by John
Cox, expanded and revised with full-colour diagrams and photographs,
dates for eclipses, meteor showers and optimum observing periods for
the planets until 2020. £4.99.

For more information on those and other Philip's titles please visit
www.philips-maps.co.uk or call 020 7644 6935 for a catalogue.


Bulletin compiled by Clive Down

(c) 2005 the Society for Popular Astronomy


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