Orbit issue 84 (January 2010)

1

2

ORBIT

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Editorial

Copy Deadline for the March 2010 issue is February 14th by which time all material intended for publication

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ISSN 0953 1599 THE JOURNAL OF THE ASTRO

SPACE STAMP SOCIETY Issue No 84 January 2010

Patron

Cosmonaut Georgi Grechko Hero of the Soviet Union

COMMITTEE

Chair Margaret Morris 55 Canniesburn Drive Bearsden Glasgow

GS1 1RX (E-mail MMorris671aolcom)

Hon Secretary Brian JLockyer 21 Exford CloseWeston-Super-Mare

Somerset BS23 4RE

(E-mail brianlockyertesconet)

Compiler of Checklist Hon Treasurer Postal Packet Organiser

Harvey Duncan16 Begg Avenue Falkirk Scotland FK1 5DL

(E-mail duncan1975btinternetcom)

Orbit Editor Jeff Dugdale Glebe Cottage Speymouth Mosstodloch Moray

Scotland IV32 7LE (E-mail jefforbitedaolcom)

Webmaster Derek Clarke 36 Cherryfield Road Walkington

Dublin 12 (E-mail dclarkeutvinternetcom)

Postal Auction Organiser David Saunders 42 Burnet Road Bradwell

Great Yarmouth NR31 8SL

Overseas Representatives

Australia Charles Bromser 37 Bridport Street Melbourne 3205 GermanyJurgen P Esders An der Apostelkirche 10 10783 Berlin

EireDerek Clarke 36 Cherryfield Rd Walkinstown Dublin 12 France Jean-Louis Lafon 23 Rue de Mercantour 78310 Maurepas

Netherlands Bart Beimers NJ Haismasrt 7 9061 BV Gierkerk Russia Mikhail Vorobyov 31-12 Krupskaya Str Kostroma

United States Dr Ben Ramkissoon 3011 White Oak Lane Oak Brook Il 60521 USA

Life Members UK - Harvey Duncan George Spiteri Ian Ridpath Margaret Morris Michael Packham Dr WR Withey Paul Uppington

Jillian Wood Derek Clarke (Eire) Charles Bromser (Australia) Tom Baughn (USA) Ross Smith (Australia)

Vincent Leung Wing Sing (Hong Kong) Mohammed KSafdar (Saudi Arabia)

End of an Era

Does 2010 signal the end of the shuttle or will there

be a full or partial reprieve as the year develops It

seems unthinkable that the Americans may soon have no means of launching men into space themselves

and will have to rely on the Russians for most of the coming decade

Am I also alone in being bewildered at the return to Apollo-like technology for the projected return to the

Moon which maynot happen in this new decade If this is the case what was the shuttle experiment all

about and is it to be regarded as a failure when so much learned about reusable hardware is being set to

one side to return to improved versions of what was

done forty years ago

Sad to relate quite possibly none of this will happen and the whole AresOrion programme will be

abandoned as unsustainable financially A recent

BBC programme about the return to the Moon envisaged four NASA astronauts landing at the same

time and then gradually a whole series of other manned and unmanned flights bringing hardware to

create a small home and then a small lunar town complete with fantastic leisure facilities which would

permit wealthy Earthlings to fly on wings by jumping

from a 50 metre board within a tall dome Alas even the most modest of these aspirations may well now

be just almost literally pie in the sky

3

ORBIT

The Sun is a star and

actually a so-called lsquowhite dwarfrsquo of the class G2

That means that it is much hotter and heavier

than a mean star but

much smaller than the blue giant stars It is estimated that today the sun is

about 45 milliard years of age and that it will live for another 55 milliard years as long as the nuclear

reactions in its core allow (USA 2000)

THE LIFECYCLE OF THE SUN The life of the sun can be divided roughly into five phases

The creation by which the sun is formed by the contraction of a large cold gaseous primeval nebula By

such a contraction gravitational energy is released which heated the core of the nebula to levels of millions

of degrees which started the nuclear reactions

The second phase as it is today the sun receives its

energy from a nuclear fusion reaction hydrogen is converted into helium and that will continue until the

hydrogen is consumed

When the hydrogen is consumed the star will become a

lsquored giantrsquo swelling temporarily to a size in which Mercury and Venus and probably even Earth will be

swallowed

When the Earth is so threatened the temperature will

rise over 1500degC and everything will become liquid At such a process helium combustion starts by which three

helium atoms will melt into one carbon core Such a reaction lasts for not more than another 100 million

years then the sun swells again and releases its outer layers into a planetary nebula

In this last phase the core remains as a lsquowhite dwarfrsquo cooling down very slowly in a billion (10-12) years and

even then the temperature will be a 1000degC

When finally the white dwarf emits no more radiation

that means that its temperature has dropped to that of the interstellar space and the sun becomes a lsquoblack dwarfrsquo

The illustration opposite (cf wwwmichielbnlod95levenhtm) shows a good image of the lifecycle of the

sun Point A is the start

of the fusion reaction ie the start of phase

two At point B about half of

the hydrogen has been

consumed and that is about todayrsquos situation

At point C the third phase starts when all hydrogen has been consumed

Point D is 15 milliard years later when the size of the sun is 33 times larger and its temperature is about

4300deg

At point E the core temperature has been raised to such a point that the helium fuses to carbon and about one

third of the sun will be blown off into space

THE SUN IN THE UNIVERSE (Mexico spiral galaxy 1942 YvAir119 WB1) (Australia spiral galaxy NGC 2997 1922 Yv1257)

The sun is located at about

27000 light years from the centre of our Milky Way galaxy

which has a thickness of about 3000 light years The

distance between the Sun

and the Earth is about 150 million km (1496) which

we call the lsquoAstronomic Unitrsquo (AU) The Sun moves

through space in a speed of

about 220 km per second and moves around the

In his new multi part series John Beenen examines the star at

the centre of our solar system

4

ORBIT

centre of our Milky Way galaxy in about 226 million

years Within this system the sun is a more or less an insignificant mean star

The sun has a mean diameter of about 14 million km

(1392) and contains 9986 of the total mass of our

solar system The mass of the sun is 21030 kg which is about 330000 times the weight of Earth

The sun is nearly a perfect sphere is not solid but is in

a constant plasma state At is equator it rotates in about 25 days but at in poles in 33 days By the ever

changing position against Earth the observed speed at

the equator is about 28 days The sun releases heat and light from its surface The temperature at the

surface is about 5800degK and at the centre is calculated to be about 155 million degrees

The pressure in the centre is also immense and is about 2x1016 Pascal (1 Pascal = 1 Nm2) Today air pressure

often is expressed as hectopascal (hPa) equal to the former millibar As the mean air pressure is about 1000

millibar the pressure in the core of the sun is 2x1011 times as high

THE COMPOSITION OF THE SUN The sun mainly consists of hydrogen in the outer layers

about 91 mol percent or 70 mass percent Further the

element helium the second element of the periodic system of elements is present in a quantity of 9 mol

percent or 28 mass percent At the centre of the sun where hydrogen is converted into helium by the fusion

reaction the content of hydrogen probably is much lower (35 mass percent)

In combination with the immense high pressure and temperatures in the centre of the sun the hydrogen

fuses into helium Every second 700 million tons of hydrogen is turned into 695 million tons of helium The

difference 5 million tons is irradiated in the form of

electromagnetic energy That seems rather a lot but it is still not more than one trillion (10-18) part of sunrsquos total

mass

The process which takes place at the core can be

compared with a giant hydrogen bomb with four hydrogen cores melting together into one helium core

At its outside the sun is surrounded by the photosphere a layer in a thickness of 300-500

km the chromosphere a very thin layer in a thickness

of about 2000 km

the corona the atmosphere of the sun extending millions of kilometres into Space

and outside prevails the heliosphere hydrogen and

helium gas blown into the interstellar space by

the solar wind and which exceeds far beyond the orbit of Pluto over one milliard kilometres

from us Further the sun shows some phenomena each of which

is interesting enough to describe and from which their

influence on our Earth and solar system has been investigated in great detail by a series of spacecraft and

probes such as solar flares prominences coronal mass ejections (CMErsquos) solar spots solar cycles magnetism

and radiation (light UV radio gamma neutrons etc)

THE PHOTOSPHERE The photosphere is the deepest layer of the atmosphere of the sun As said it has a thickness of 300-500 km

and nearly all the light we receive from the sun

originates from this layer The name comes from lsquofotoosrsquo ancient-Greek for lsquolightrsquo The downside of this layer applies to the lsquorsquosurfacersquo of

the sun Actually it is not a real surface as the sun is a

gaseous sphere In the photosphere the temperature from about 6500degK at the surface drops to about 4500deg

K at the upper limit The density of the photosphere is already very low compared to our earth atmosphere

and it about 4000 times lower at the upper limit even 200000 times

The photosphere we see as a granulated wriggling constant changing pattern of magnetic cells of hot gas

The sunrsquos photosphere is composed of convection cells called granules ndash cells of gas 50-1000 km in diameter

with hot rising gas in the centre and cooler gas falling in

the narrow spaces between them Each granule has a lifespan of about eight minutes resulting in a

continually shifting lsquoboilingrsquo pattern but much longer lifetimes have been observed Grouping the typical

granules are super granules up to 30000 kilometres in diameter with lifespans of up to 24 hours

THE CHROMOSPHERE (Dutch Antilles solar eclipse 1998 NVPH1202)

The chromosphere lies next to the

photosphere and has a thickness of about 2000 km It is even thinner

than the photosphere and shows a

reddish colour which can be seen at solar eclipse Strangely enough the

chromosphere shows much higher temperatures even going up to

20000degK

Even today the cause of this phenomenon is still not

explained completely Sonic turbulence is one of the explanations but newer theories prefer a magnetic

cause The most common phenomenon in the

chromosphere is the occurrence of so-called lsquospicularsquo eruptions of long thin fingers of luminous gas which

5

ORBIT

appear like the blades of a huge field of fiery grass

growing upwards from the photosphere below Spicules rise to the top of the chromosphere and then sink back

down again over he course of about 10 minutes

Another feature found in the chromosphere are lsquofibrilsrsquo horizontal wisps of gas similar in extent to spicules but with about twice the duration Finally lsquosolar prominencesrsquo rise up through the chromosphere from the photosphere sometimes reaching altitudes of

150000 km These gigantic plumes of gas are the most spectacular of solar phenomena aside from the less

frequent solar flares

(Niger year of the quiet sun 1964 Yv144 WB 7)

In 1997 the space craft SOHO

observed a prominence in a length of 350000 km but even longer ones up

to one million km were observed

Generally they are formed in one day

but stay visible over months

Starting from solar flares or p rom ine nce s some t imes lsquo co rona l ma s s ejectionsrsquo (CMErsquos) are formed tremendous loops of

material from the corona blown by the sun with speeds over one million km per hour

Such eruptions contain over ten times as much energy

as the solar flares of prominences from where they

originate and may carry hundred of millions of tons of mass into space It is assumed that such eruptions are

the consequence of instabilities in the magnetic field

THE CORONA (Mali year of the quiet sun 1964 Yv67 WB 3)

The corona is a kind of plasma

atmosphere surrounding the sun or another celestial body

The Latin root of the word

lsquocoronarsquo means lsquocrownrsquo The temperature of the corona is

strangely high about one million times thinner than the

photosphere it shows a temperature up to one to three million degrees

The corona is divided into three areas

the K-corona (K for continuum) interfaces directly with the chromosphere and is created by

sunlight scattered off electrons the E-corona (E for emission) contains abundant

calcium and iron

the F-corona (F for Fraunhofer) is created by sunlight bouncing off dust particles

(Bulgaria 1965 year of the quiet sun Yv1384 WB 50)

The precise cause of the

strangely high temperature

is still not very well known Many coronal heating

theor ies have been proposed but two theories

have remained as the most likely candidates wave heating and magnetic reconnection (or nanoflares) but neither theory has been able to account for the extreme

coronal temperatures Most solar physicists now believe that some combination of the two theories can probably

explain coronal heating although the details are not yet complete

The phenomenon will be investigated in greater detail by the Solar Probe Plus probe possibly to be launched

in 2015 This satellite will approach the sun closer than ever before The lsquowave heatingrsquo theory was proposed

in 1949 by the French astrophysicist Evry Schwarzman

(1920) who assumed that waves transport energy from the inner of the sun to the chromosphere and the

corona (Bulgaria 1965 year of the quiet sun Yv1383 WB49)

The sun is made of plasma

rather than ordinary gas so it supports several types of

waves analogous to sound

waves in air The most important types are the

magneto-acoustic and the Alfveacuten-waves called after the Swedish plasmaphysicist Hannes Alfveacuten (1908-1995)

Magneto-acoustic waves are sound waves that have

been modified by the presence of a magnetic field and Alfveacuten-waves are similar to ULF radio waves that have

been modified by the interaction with matter in the plasma

Still we know little about it but both types of waves

may escape from the sun by the turbulence of

granulation and super granulation at the solar photosphere and both types of waves can carry energy

for some distance through the solar atmosphere before turning into shock waves that dissipate their energy as

heat Yet the effects of both wave types are actually

unsuitable to give a full explanation of the complete effect

Also the lsquomagnetic reconnectionrsquo theory knows its limits

relying on the solar magnetic field to induce electric

currents in the solar corona The currents then collapse suddenly releasing energy as heat and wave energy in

the corona This process is called lsquoreconnectionrsquo because of the peculiar way that magnetic fields behave in a

plasma In a plasma magnetic field lines are normally tied to individual places of matter so that the topology

6

ORBIT

of the magnetic field remains the same if a particular

north and south magnetic pole are connected by a single field line then even the plasma is stirred or if the

magnets are moved around that field line will continue to connect those particular poles The connection is

maintained by electric currents that are induced in the

plasma Under certain conditions the electric currents can collapse allowing the magnetic field to lsquoreconnectrsquo

to other magnetic poles and release heat and wave energy in the process

Magnetic reconnection is hypothesized to be the

mechanism behind lsquosolar flaresrsquo the largest explosions

in our solar system The idea that micro flares might heat the corona was put forward by the American

astrophysicist Eugene Parker but is still controversial

Ultraviolet telescopes such as TRACE and SOHOEIT can

observe individual micro flares as small brightenings in extreme ultraviolet light but there seem to be too few

of these small vents to account for the energy released into the corona whose outer layer is continuously

blown into Space by a magnetic flux in the form of lsquosolar windrsquo

The corona is not always evenly distributed across the surface of the sun During periods of quiet the corona

is more or less confined to equatorial regions with coronal holes covering the polar regions However

during the Sunrsquos active periods the corona is evenly

distributed over the equatorial and polar regions though it is most prominent in areas with sunspot

activity

Coronal loops are the basic structures of the magnetic

solar corona Loops of magnetic flux well up from the solar body and fill with hot solar plasma Due to the

heightened magnetic activity in these coronal loops regions coronal loops can often be the precursor to

solar flares and Coronal Mass Ejections (CMErsquos)

A photo made by TRACE (Transition Region and

Coronal Explorer also Explorer 73) launched at 1 April 1998 shows such a lsquolooprsquo The corona is most easily

seen during a total solar eclipse as a nimbus around the sun

SOLAR FLARES (Czechoslovakia 1965 year of the quiet sun Yv1381 WB 47 USA 1958 intgeophysical year Yv 643 WB 2)

A solar flare is a violent explosion in a starrsquos

atmosphere releasing as much energy as6x1025

Joules Solar flares take

place in the solar corona and the chomosphere

heating plasma to ten of millions of kelvins and

accelerating electrons protons and heavier ions to near the speed of light Originating from the corona such

t r e m e n d o u s e x p l o s i o n s a r e c a l l e d CMErsquos (Coronal Mass Ejections)

They produce electromagnetic radiation across the electromagnetic spectrum at all wavelengths from long-

wave radio to the shortest wavelength gamma rays Most flares occur in active regions around sunspots

where intense magnetic field emerge from the Sunrsquos surface into the corona Flares are powered by the

sudden (timescales of minutes to tens of minutes)

release of magnetic energy stored in the corona

X-rays and UV radiation emitted by solar flares can affect Earthrsquos ionosphere and disrupt long-range radio

communications Direct radio emission at decimetric

wavelengths may disturb operation of radars and other devices operating at these frequencies

Solar flares were first observed by the British

astronomer Richard Christopher Carrington (1826-1875) and independently by Richard Hodgson Esq of Highgate

in 1859 In September of that year probably the largest

solar flare of the last 500 years was registered which could be derived from measurements on nitrates and

the element beryllium-10 in the ice mantle of Greenland

The frequency of the occurrence of solar flares varies from several per day when the Sun is particularly

lsquoactiversquo to less than one each week when the Sun is lsquoquietrsquo Large flares are less frequent than smaller ones

Solar activity varies with an 11-year cycle (the solar

cycle) At the peak of the cycle there are typically more sunspots on the Sun and hence more solar flares

Solar flares are classified as A B C M or X according to

the peak flux (in watts per square meter Wm2) of 1200 to 800 picometer X-rays near Earth as measured

on the GOES (Geostationary Satellite) spacecraft The

first one of this type was launches 16 October 11975 The last one at this time GOES-13 dates 24 May 2006

(Cayman Islands 1991 M642 WB4)

The most powerful explosion

ever was recorded by GOES

on the 4th of November 2002 with a power between 4-45

MWm2

Solar flares and associated CMErsquos strongly influence our

local lsquospace weatherrsquo They produce streams of highly energetic particles in the solar wind and the Earthrsquos

magnetosphere that can present radiation hazards to spacecraft and astronauts The soft X-ray flux of X class

flares increases the ionisation of the upper atmosphere which can interfere with short-wave radio

7

ORBIT

communication and can increase the drag on low

orbiting satellites leading to orbital decay Energetic particles in the magnetosphere contribute to the aurora borealis and aurora australis

Hungary 1965 year of the quiet sun Yv1718 WB 99-103 Australia Antarctica 1966-68 Yv 8 Mongolia 1965 year of the quiet sun Yv 334 WB 20-22

Solar flares release a

cascade of high energy particles known as a

lsquoproton stormrsquo Protons can pass through the

human body doing

biochemical damage Most proton storms take two or more hours from the

time of visual detection to reach Earth A solar flare on January 20 1005 released the highest concentration of

protons ever directly measured taking only 15 minutes

after observation to reach Earth indicating a velocity of approximately one-third light speed The radiation risk

posed by solar flares and CMErsquos is one of the major concerns in discussions of manned missions to Mars or

to the Moon Some kind of physical or magnetic shielding would be required to protect the astronauts

Solar flares have been observed by a great many of spacecrafts such as the Japanese Yohkoh (Solar A)

launched 13-08-1991 the previously mentioned GOES the RHESSI (Reuven Ramati High Energy Solar

Spectroscope Imager) launched 02-20-2002 and the

other Japanese Hinode (Solar B) launched 23-09-2006

Some other solar experiments were carried out by the

Sovjets and Russia with the Vertikal 1-11 launched within the framework of the Interkosmos project The

first Vertikal was launched on November 28 1970

Also Coronas-1 (2 March 1994) and Coronas-F (31-

07-2001) investigated the sun These Coronas-series of experiments are not to be confused with the American

observation satellites for military purposes lsquoCoronarsquo

launched since the sixties

Most probes investigated all kinds of radiation emitted by the Sun The Hinode probe particularly measured the

solar flares The Rhessi program was a cooperation of

many countries The Yohkoh discovered that lsquomagnetic reconnectionrsquo was the basic phenomenon responsible

for solar flares

In the meantime it was discovered that solar flares could cause very heavy solar quakes

Such a phenomenon first was detected by Alexander

Kosovichev of the University of Stanford and Valentina Zharkova of the University of Glasgow

SOLAR WIND AND HELIOSPHERE

The heliosphere is an area in Space taken by the effects of the sun such as gases blown by the solar wind into

Space The first 10 milliard of kilometres the solar wind

are blown in a speed over one million kilometre per hour (350-700 kmsec) In fact there are two speeds

the wind originating from the poles being blown in a somewhat higher speed than that from the equator

At the borders of our solar system the wind bounces into the interstellar medium and reduce in speed Solar

wind is a stream of charged particles It consist mostly of high-energy electrons and protons (about 1 KeV) that

are able to escape the Sunrsquos gravity in part because of

the high temperature of the corona and the high kinetic energy particles gain through a process that is not well

understood at this time

The solar wind is emitted when the Sunrsquos magnetic field loops out into space instead of looping back into the

Sun These magnetic anomalies in the Sunrsquos corona are

called lsquocoronal holesrsquo Such holes are very stable and may stand for months even years Sometimes gigantic

explosions are observed by which much more particles are created in the form of solar wind Such explosions

are called lsquoCoronal Mass Ejectionsrsquo (CMErsquos) and belong

to the largest explosions in our solar system

In 1997 such an explosion was observed for the first time from its creation until its arrival and its

consequences on Earth four days later These bursts release up to 100 milliard kg (1011 kg) of plasma with a

speed in the neighbourhood of that of light Their force

can be compared with that of one milliard hydrogen bombs

With a mean speed of 400 kmsec the solar wind covers

the distance to Earth in 45 days However we have not

to think in terms of earth wind Solar wind is very thin It contains not more than 3-6 ions per cm3 hence space

is very empty

As the particles are released from a rotating sun they

move in the shape of an arithmetic spiral The American astrophysicist Eugene Parker (1927) investigated this

8

ORBIT

effect into great detail and

discovered that the spinning particles show the

shape of a twirled ballerina skirt a lsquoParker spiralrsquorsquo

Solar wind is noticeable throughout the whole solar

system Comets can be affected by its influence therefore their tails are always directed away from the

sun as detected for the first time in the fifties by the German physicist Ludwig Biermann (1907-1986)

As said the solar wind creates the lsquoheliospherersquo an interstellar region surrounding the Sun Even before

the space age solar wind was presumed already by Birkeland (1916) Lindemann (1919) but could be

measured only after the first spacecraft reached their

orbits the Soviet satellites Luna 1 2 and 3 and the Venera 1 Also the American Mariner 2 presented

results in this respect The Mariner 2 also detected that the speed of the solar wind even measured in days

was varying very much and that this was connected to the rotation of the sun in about 27 days

Despite further observation eg of the SOHO-probe (Solar and Heliospheric Observatory) it still is not clear

which mechanism or mechanisms are exactly responsible for the acceleration of the solar wind

How many particles escape the gravity of the sun has been measured a great many 67 milliard tons per

hour a mass as large as the earth every 150000 year but still not more than 001 of the sun Solar wind

consists of plasma 95 of hydrogen in ionized form

4 double ionized helium and less than 05 other ions of carbon nitrogen oxygen neon magnesium

iron and silica such as measured by thew spacecrafts Ulysses (370 kg 6 October 1990 from the STS-41

Discovery) and ACE (Advanced Composition Explorer 785 kg 25 August 1997)

Fortunately Earth is protected by its magnetic shield which deviates most of these particles However a

small amount of these particles are captured in both the van Allen belts surrounding the earth at resp 01-

15 (2000-5000 km) and 4-514500-19000 km) earth

diameters around the earth But as the Moon has no atmosphere and no magnetic field its surface is

completely exposed to the radiation of the solar wind

The point where the solar wind slows down to subsonic speed (100 kmsec) is called the lsquotermination shockrsquo The exact point is not known but it is believed that it is

between 75 and 90 AU from the sun far surpassing the planet Pluto (394 AU)

On August 30 2007 Voyager 2 crossed this border

Before this at 23-24 May 2005 ndash another source

mentions December 2004 ndash this border was reached by

Voyager 1 at a distance of 94 AU It is certain that

this limit varies somewhat influenced by bursts and explosions at the sun It is expected that better

information will be collected by the probe IBEX (Interstellar Boundery Explorer) launched in October

20 2008 Pioneer 10 and 11 also delivered data

with respect to the solar wind

After passage of the termination shock the region is called lsquoheliosheathrsquo which continues until the moment

where the speed of the solar wind is in balance with

that of the interstellar medium This limit is called lsquoheliopausersquo and is considered as the end of our solar

system

Its distance is thought to be found at 100-200 AU in

any case much further than the planet Pluto (395 AU) At present the heliosheath is investigated by both the

Voyagers It is supposed that the heliosheath has a thickness of 10-100 AU but its precise thickness and

form is still very uncertain

SOLAR CYCLE SUN SPOTS The first record of sunspots dates to around 800 BC in China and the oldest surviving drawing of a sunspot

dates to 1128 A large sunspot also was seen at the

time of Charlemagnersquos death in AD 813 Sunspot activity in 1129 was described by John of Worcester In

1608 the telescope was invented by the Dutchman Hans Lippershey which meant an enormous increase in

the amount of observations with respect to celestial bodies

Sunspot are regions on the Sunrsquos surface marked by an intense magnetic activity which inhibit convection

Forming areas of reduced surface temperature They are visible from the earth as dark spots at the surface

It has been detected that sunspots appear in periods of

11 years

This lsquosolar cyclersquo was discovered in 1843 by the German physicist Samuel Heinrich Schwabe (1789-

1875) and perfected by the Swiss astronomer Rudolf

Wolf (1816-1893) The amount and activity of sun spots is expressed in a parameter lsquothe lsquoWolf

9

ORBIT

numberrsquo (or

lsquo Z uuml r i c h numberrsquo)

The solar

cyc le (o f

m a g n e t i c activity) is a

cycle of 11 years (actually 22 years) and is powered by a

hydromagnetic dynamo process driven by the inductive action of internal solar flows The process is visible by a

more or less regular increase and decrease of sunspots

and magnetic activity

The 11-year cycle is also called the lsquoSchwabe cyclersquo the 22-year cycle is known as the lsquoHale cyclersquo Even other

cycles are found such as the lsquoGleisberg cyclersquo of 87

years the lsquoSuess cyclersquo of 210 years and the lsquoHallstadt cyclersquo of 2300 years Even more supposed cycles are

known

However the 11 year cycle is not completely constant and deviations up to 9-14 years have been observed

Between 1645 and 1715 a period known as the lsquolittle ice agersquo very few sunspots were observed This period also is known as the lsquoMaunder Minimumrsquo after the

British astronomer Edward Walter Maunder (1851-1928) who investigated this period intensively Together with

his wife Annie

M a u n d e r h e constructed his well

-known butterfly diagram of the

activity of the sun

and its cycles

In the second half of the 19th century

the British astronomer Richard Carrington (1826-1875) and the German Gustav Spoumlrer (1822-1895) discovered

that as the cycle continued the spots moved from the

equator to the poles where they arrived at minimum activity

In 1908 the American astrophysicist George Ellery Hale

(1868-1938) and his co-operators showed that sun

spots were largely magnetic and in 1919 they also demonstrated that the magnetic polarity of the spots

appeared in pairs In fact the solar cycle lasts for 22 years after 11 years the same configuration starts

again but in a reversed polarity Hale is better

known as the founder of

the MtWilson observatory at Pasadena South

California in 1904 (USA 2000 from bloc lsquoProbing the vastness of spacersquo)

Around 190 the influence of the sun on the conditions

of Earth was looked into specially by Charles Greely Abbot (1872-1973) of the Smithsonian Astrophysical

Observatory (SAO) who carried out much investigations after the periodically appearing phenomena of the sun

After the work of the American dendrobiologist Waldo

SGlock such phenomena of the sun could be connected to variations in the growth of trees

At the beginning of the 19th century the famous British

astronomer William Herschel (1738-1822) was thought to have found a connection between the occurrence of

sunspots and the prices of grain But he also thought

that there could live creatures at the sun with enormous heads to stand against the high temperatures

Half a century later the American father and son Harold

(1882-1968) and Horace Babcock (1912-2003) showed

that the magnetism of the sun spread over the whole surface and that the solar cycle is a process taking place

all over the sun

The new solar cycle number 24 is considered to start at the moment where the amount of new sunspots

exceed the amount of sunspots from the last cycle

Based upon the reversion of the polarity January 4th 2008 was chosen as the start point of the new cycle

but based upon the sunspots the beginning of 2009 is more likely Anyhow even today where the solar cycle

shows a minimum the sun is relatively in a very active

state not seen the last 8000 years The level over the last 70 years is rather exceptional

The next list may explain this

Source httpenwikipediaorgwikiSolar_variation

It is therefore not surprising that there are some

scientists who make the appearance of sunspots and the increased activity of the sun more responsible for

the present climate problem And there are even more

influences of the sun from which it is supposed that they have an influence on our living circumstances such

as changes in the total amount of light

changes in the amount of UV-radiation

changes in solar wind and magnetic flux

Period Remarks Start year End of

Period

Level of activity

Oort minimum Warm period in the Middle ages 1040 1080 -6

Medieval maximum 1100 1250 -20

Wolf minimum 1280 1350 +1

Spoumlrer minimum 1450 1550 +12

Maunder minimum Little ice age 1645 1715 +17

Dalton minimum 1700 1820 -2

Modern maximum 1950 Today gt-20

10

ORBIT ORBIT

effects on cloud formation (formation of

condensation nuclei) geomagnetic storms

exceptional proton emissions variations in galactic cosmic radiation

formation of C-14 (carbon-14)

On all these subjects scientists discuss about their

influence on our climate But the fact is that over the last 70 years the sun is very active and this must have

its influence on our living conditions But one has to remember that data from long ago certainly could be

less reliable and extrapolation therefore may be tricky

That does not mean that carbon dioxide and methane gas have no influence but only that we have to be

careful not to take our conclusions too quick and too definite

Sunspots can live for some days but also for months Finally they disappear emitting a large amount of

magnetic flux to the photosphere Also the strengths of light radiation varies with the amount of sunspots

and is the largest in periods with the maximum of activity

Furthermore variations are found in the emission of extreme UV-radiation (EUV) and roentgen-radiation

Such effects have been measured by the Japanese probe Yohkoh and the American SOHO and TRACE

The effect of such kind of radiation on the

magnetosphere of the earth is large It is the most important booster of the chemistry of the stratosphere

and increases the ionising radiation influences the temperature and the electric conductivity in the

ionosphere

Observations on sunspots also have been carried out

by the crew of Skylab 2 and 3 During the flight of Skylab 2 (25-03-73 to] 22-7-73) the sun was very

active The crew of Skylab 3 (28-07-73 to 25-09-73) for a couple of days observed however a complete

quiet sun The Skylabs carried out much more sun

observations and brought back a wealth of scientific information with regard to the magnetism of the sun

solar flares sunspots and radiation Much of these and other data collected by different spacecrafts and

probes are available at the Internet in the lsquoSolar Data Analysis Centerrsquo (SDAC) (httpnasasciencenasagovheliophysics)

In the next part of this series John details probes sent to the

Sun and other solar experimentation

ASTEROIDS Some Bits and Pieces

Correction Thanks to Peter Hoffman for pointing out that the above mini-sheet which I placed on the back page of

our last edition along with Apollo XI commemoratives

has nothing at all to do with that flight but in fact marks both the world record breaking flight of Apollo X

flight and the pioneering earth orbiting experience of the cosmonauts of Soyuz TM 18 in 1994 Apologies for

this error

Italia 2009 The Rome International Festival of Philately which ran from 21-25 October was able to put on display (at the

Vaccari stand) the diary kept by Anatoli Berezovoi

during his 211 days in space from mid Maymdashmid December 1982

Finbar Kenny Khalid Omaira of the Arabian Gulf Postal History Quarterly Journal as been in touch with the Society to ask for any info members might have about the part

played by the American philatelic entrepreneur Finbar

Kenny in producing space (and other) stamps for the Trucial States at the end of the 1960s If you would

like to contribute to Khalidrsquos research please contact him at a6zsnhotmailcom

Ad Astra Our Italian sister journal continues to thrive and grow

thanks to the excellent work of former ASSS member

Umberto Cavallaro in producing this bi-lingual production now in edition no 4 and if you would like to

read it in electronic form for a modest fee please contact Umbertohellipat ucavallaroaliceit

11

ORBIT

Part 3 of 3 From Bert van Eijck

In the final part of this short series we deal with private cancellations on official cancels and stamps from postal authorities These fraudulent cancels were mainly used on American launch covers for satellites or probes in the 1980rsquos The maker of these cancels was a German dealer who of course wanted to sell more covers Nowadays you often find these covers in auctions Beware though for they are prohibited in exhibitions and can give you fewer points or even mean your disqualification To give you an idea what we are talking about here are some examples of such cancels on cover First (above) we see a US aerogramme for Halleyrsquos Comet with the official US cancel for Houston integrated in a fraudulent cancel with the text

ldquoInternational Halley Watch US-German CooperationmdashGerman First Day of Issuerdquo Both cancels are now ONE cancel even in the shape of a comet Next to the US pre-stamp there is a hellipGerman stamp A second example FDC for the Halleyrsquos Comet 80Pf stamp from Germany with the same integrated cancel as above so you see a German stamp with a US cancel The cancel of the Houston Satellite Station is another story however This cancel was made by the German dealer and offered for use at the Houston Post Office on June 20 1986 First this was granted but later on denied Nevertheless the dealer and his personnel used it to cancel the covers with Both fraudulent cancels are enlarged in an official warning press release of the USPS dated April 1987 The German dealer defended himself in his monthly news magazine Weltraum Philatelie Report of May 1987 saying that the USPS itself does not always match the proper philatelic

standards For example the STS-8 cover with five different cancels like ldquoOrbited via STS-8rdquo was prepared before launching Nevertheless the dealer was willing to take back the suspect covers and return buyers their money Opposite - enlarged examples of the cancels from the USPS warning release