WADHURST ASTRONOMICAL SOCIETY
MARCH NEWSLETTER 2006
INDEX: MEETINGS, OTHER NEWS, CONTACTS
Habitability of Planets
given by Dr. Martin Heath at the Society's February meeting on Wednesday 15th
Dr. Martin Heath has recently been involved in a programme on Channel 4
about Alien Worlds, and with this in mind we began an adventure into the search
for the possibility of life somewhere else amongst the Solar planets and planets
around other stars.
Up until the middle of the 18th century Martin said that the feeling was
held that it was likely that other planets in the Solar System were inhabited,
otherwise why would they be there if no-one lives on them.
Although we now know that only the Earth is inhabited at present, it is
possible that other planets have had life on them in the past and maybe may have
life on them in the future as conditions change within the Solar System as it
Although certain conditions must be present for life to exist, it is
strange that it is impossible to perfectly sterilize anything on Earth at
Martin then showed a slide with millions of stars and posed the question
- what is the chance of there not being life on planets around these star
systems. He spoke of Marconi's
radio experiments at the Needles on the Isle of White when it had been suggested
that some of the received "noise" could well be coming from outer
space. Also other astronomers and
scientists, including Carl Sagan had suggested hat there are probably millions
of other beings; - but ask the question - where are they?
Do we have to reach a certain intellectual level to communicate with
extra-terrestrial life? Might it be
possible that there are bacteria everywhere in the Solar System?
There maybe higher life but without the ability to move as we do.
He mentioned that our nearest star, Alpha Centauri is travelling relative
to us at 22 kilometres per second and would seem to be passing by, perhaps
carrying alien life of some kind.
William Herschel in the city of Bath looked at the moon through his
telescopes and wondered if there could be life there.
Schiaparelli was an Italian astronomer and observed long lines on the
surface of Mars, which he called Canali, which means channels or grooves and
which many people took to mean constructed waterways.
Astronomer Percival Lowell at Flagstaff in Arizona thought he could see
areas of vegetation and deserts on the surface of Mars, which increased the
desire to search for life on other planets.
Martin introduced us to Barnard who was the astronomer responsible for
discovering one of Jupiter's moons and also for Barnard's star, one of the Sun's
closest neighbours. If planets could be detected from Earth, then perhaps this
was a good place to start although nothing has been detected so far.
A pair of dwarf stars observed rotating around each other with an orbit
whose plane is level with the Earth give the possibility of detecting a planet
if measured light from one of the pair was to diminish briefly.
This has not been detected yet.
We moved to SETI, the Search for Extra Terrestrial Intelligence Institute
although Martin did say that public money could no longer be used for this
research. Never the less a great
deal of interest is being shown in the work of the institute.
Having talked about there being virtually no chance of life on the outer
planets and after visits to Mars, no evidence for life there had been found and
the plate-like structure of the surface of Venus suggested that this planet is
We were then taken on a tour round the Earth to view the volcanoes of
Hawaii looking rather like Olympus Mons on Mars, then to look at the
Mid-Atlantic Ridge where Plate Tectonic activity was resulting in Himalayan like
structures. We looked at the cold
currents of the Pacific and then on shore we looked at slides of the San Andreas
Fault; all showing that there is a lot of geological change going on.
We have developed ways to keep warm or cool, as we need, indicating that
the Earth is changing within conditions that support life as we know it. The
natural temperature of the Earth is about -20 degrees Celsius and is only higher
because of the presence of carbon dioxide.
Our own planetary system is fairly simple with the moon helping to give
the earth its vital seasons. Martin went on to say that it might be possible for
a planet to exist in a stable orbit around a pair of orbiting stars provided it
was at least 5 times the distance between the stars.
Another problem could be the life of the star or stars around which any
planets might be orbiting. Sirius
and Proycon may only last about 700 million years whereas our Sun will probably
last about 10,000 millions years, which is quite reassuring, although on the
down side, it will become a Red Giant towards the end of its life, swallowing
An excellent talk although with a warning that during the next century we
need to act to preserve life as we know it.
Those at the meeting will be relieved to know that Martin's rapid
departure to catch a train from Wadhurst Railway station with transport provided
by Michael Harte was successful!
Wednesday 15th March 2006
Martin Frey talks about "Great Astronomical Blunders"
Wednesday 19th April 2006 Our
own Ian King tells us about "Instrumentation".
Wednesday 17th May 2006 Dr.
Robert Smith gives a talk with the alarming title of "Things that go Bang
in the Night"
Wednesday 21st June 2006 We
are to have a Members evening called "Summer Solstice Telescope
Evening" when members are invited to bring their telescopes and any other
astronomical equipment and when we get the chance to discuss our interests.
If any member would be interested in giving a short talk, they would be
very welcome and should contact either Phil Berry, Ian Reeves or Geoff Rathbone.
Wednesday 19th July 2006 Gilbert
Satterthwaite FRAS will be talking to us about "Sir George Airy's
Contribution to Positional Astronomy".
be no August meeting but Michael Harte is again kindly offering to hold a barbecue
on 26th August. Details to follow.
GO TO INDEX
Ian Reeves, one of our Secretaries, has been approached by the Eridge
Pony Club who have been donated a Celestron 114 telescope complete with tripod.
They feel it is far too good for a jumble sale!
Anyone interested in purchasing it should contact Sue Port direct on
01892 784438 for further details.
TALK ON ASTRONOMY REQUESTED FROM OUTSIDE THE SOCIETY
Would any member of the Society be prepared to give a talk on the 20th
of February or the 20th of March 2007 in Tunbridge Wells on the lines of "An
Introduction to the Sky at Night" or similar title of the Speaker's choosing?
We have been asked by the Soroptomists Society (a group of business ladies)
which has a membership of between 25 and 30.
Would the volunteer(s) kindly advise Ian Reeves?
Apart from the Spring Equinox at about 0600 on 20th March the sky this
Month is dominated, one way and another, by the Moon.
Right at the end of the month on 29th March there is a total eclipse of
the Sun, but only partially visible from the UK. At least one of our members is
off to Turkey to witness the event in full and we wish him clear skies.
In Kent we will be able to see approximately 17% of the Sun's surface
covered by the Moon at 1130 (British Summer Time - which begins on Sunday 26th
March) and is an occasion still worth observing.
First point of contact for Wadhurst is at 1048 and last contact is at
1222. There are several safe ways to see this partial eclipse; by
projection; through a Mylar solar filter or looking at the shadow effect through
a series of holes or on the ground through trees (if there are any leaves at
this time of year). During the last
partial eclipse I used our kitchen colander and the result was quite striking.
As often is the case, the orbit of the Moon at the time of a solar
eclipse can result in an eclipse of the moon either two weeks afterward or in
this case, two weeks before on the evening of the 14th March.
This is only a Penumbral eclipse which means that the Earth's atmosphere
does the eclipsing, not the planet itself, resulting in darkening of part of the
Yet again, the Moon sets another notable record this month by being at
its lowest altitude at transit since 1950.
On 22nd of March it reaches a maximum of -29 degrees below the ecliptic
or just 9.3 degrees above the southern horizon, - although this is at 0530 in
Venus is the bright planet in the early morning, rising about 90 minutes
before the Sun.
Mars is now receding from us but is still well placed for observing, as
is Saturn, which has just passed opposition.
Saturn's rings are beginning to close as observed from Earth, but we
still have until 2009 before they are completely edge on.
Jupiter rises just after midnight and transit occurs at 0430.
Since it is about magnitude -2 it should be possible to find it in the
SSW sky as the Sun is rising.
Patrick L. Barry
Future space telescopes might not consist of a single satellite such as
Hubble, but a constellation of dozens or even hundreds of small satellites, or
"micro-sats," operating in unison.
Such a swarm of little satellites could act as one enormous telescope
with a mirror as large as the entire constellation, just as arrays of
Earth-bound radio telescopes do. It
could also last for a long time, because damage to one micro-sat wouldn't ruin
the whole space telescope; the rest of the swarm could continue as if nothing
And that's just one example of the cool things that micro-sats could do.
Plus, micro-sats are simply smaller and lighter than normal satellites,
so they're much cheaper to launch into space.
In February, NASA plans to launch its first experimental micro-sat
mission, called Space Technology 5. As
part of the New Millennium Program, ST5 will test out the crucial technologies
needed for micro-sats-such as miniature thrust and guidance systems-so that
future missions can use those technologies dependably.
Measuring only 53 centimetres (20 inches) across and weighing a mere 25
kilograms (55 pounds), each of the three micro-sats for ST5 resembles a small
television in size and weight. Normal satellites can be as large and heavy as a
"ST5 will also gather scientific data, helping scientists explore
Earth's magnetic field and space weather," says James Slavin, Project
Scientist for ST5.
Slavin suggests some other potential uses for micro-sats:
cluster of micro-sats between the Earth and the Sun-spread out in space like
little sensor buoys floating in the ocean-could sample incoming waves of
high-speed particles from an erupting solar flare, thus giving scientists hours
of warning of the threat posed to city power grids and communications
Or perhaps a string of micro-sats, flying single file in low-Earth orbit,
could take a series of snapshots of violent thunderstorms as each micro-sat in
the "train" passes over the storm.
This technology would combine the continuous large-scale storm monitoring
of geosynchronous weather satellites-which orbit far from the Earth at about
36,000 kilometres' altitude-with the up-close, highly detailed view of
satellites only 400 kilometres overhead.
If ST5 is successful, these little satellites could end up playing a big
role in future exploration.
The ST5 Web site at nmp.jpl.nasa.gov/st5 has the details.
Kids can have fun with ST5 at spaceplace.nasa.gov, by just typing ST5 in
the site's Find It field.
article was provided by the Jet Propulsion Laboratory, California Institute of
Technology, under a contract with the National Aeronautics and Space
GO TO INDEX
Secretary Phil Berry 01892 783544
Any material for inclusion in the April Newsletter should be with the Editor by March 28th 2006
GO TO INDEX