Smithsonian miscellaneous collections

SMITHSONIAN MISCELLANEOUS COLLECTIONS

VOLUME

95,NUMBER11

Hrtbur jfunb

INFLUENCE OF PLANETARY CONFIGURATIONS UPON THE FREQUENCY OF VISIBLE

SUN SPOTS

BY

FERNANDO SANFORD

PaloAlto,California

(Publication 3391)

CITY OF

WASHINGTON

PUBLISHED BY

THE

SMITHSONIAN INSTITUTION

JUNE

5, 1936

SMITHSONIAN MISCELLANEOUS COLLECTIONS

VOLUME

95,NUMBER

U

Hrtbur Jfunb

INFLUENCE OF PLANETARY CONFIGURATIONS UPON THE FREQUENCY OF VISIBLE

SUN SPOTS

BY

FERNANDO SANFORD

PaloAlto,California

(Publication' 3391)

CITY OF

WASHINGTON

PUBLISHEDBY

THE

SMITHSONIAN INSTITUTION

JUNE

5. 1936

BALTIMORE,MD., U.8.A.

Brtbur

f\\nt>

INFLUENCE OF PLANETARY CONFIGURATIONS UPON THE FREQUENCY OF VISIBLE SUN SPOTS

By FERNANDO SANFORD

Palo Alto, California

Inanydiscussion of sun-spotfrequencyitshould bebornein

mind

that only one-half of the

Sun

isvisibleto usat one time,

and

that all sun-spot data refer only to spots on the terrestrial side of the Sun.

In1907 A.S.D.

Maunder

published apaperentitled

"An

xA.pparent Influence of the Earthonthe

Numbers

and Areas of Sun-spots in theCycle 1889-1901."^{^} Mrs.

Maunder

foundthatfor the yearsunder consideration

more

spots

came

intoview aroundtheeast limb of the

Sun

than passedout ofview aroundthewestlimb;thatis,that

more

spots died outonthevisiblesideof the

Sun

thanwere

formed

onit.

As

a

summary

of Mrs. Maunder's observations

we

havethe follow- ingtal)le

:

Spotsborn onvisiblehemisphere 384 Spotsbornoninvisiblehemisphere 5/2 Spots died onvisiblehemisphere 564 Spots diedoninvisible hemisphere 402

Alltold,947 groups

came

intoview aroundthe eastlimb orformed close toit, and only/"/y groups passed aroundthewest limb ordis- solvedclose toit. This leaves a difference of 170groups, or 22per- cent of the disappearances, which seem to bedue to

some

influence exerted by the Earth. Apparently, the Earth exerts an inhibitive influence

upon

the formationof sun spots

upon

its

own

sideof the

Sun

or aids theirformation

upon

the oppositeside, or,perhaps, both.

This plain inference seems not to have been tested in the case of otherplanets.

ItisreasonabletoinferthatwhateverinfluencetheEarth

may

have on sunspots,a similar influence

may

be exertedbytheplanetVenus, which is comparable in size and massto the Earth and is less than

'MonthlyNot.Roy.Astronom.Soc,

May

1907.

Smithsonian MiscellaneousCollections, Vol.95,No.11 I

2

SMITHSONIAN MISCELLANEOUS

COLLECTIONS VOL. 95

three-fourths the Earth's distance

from

the Sun. If such should prove to he the case, the visible spottedness of the

Sun

should be decreased

when Venus

and the Earth are on the

same

side of the Sun,orincreased

when

they areonoppositesides,orboth

phenomena

should appear.

In the publications of

The

International Astronomical

Union

are given thedailyvalues of the sun-spotrelative

numbers

beginning with 191^7.

The mean

synodical period of

Venus

is 584 days.

The

daily sun-spot

numbers

for 10 synodical periods of Venus, beginning at superiorconjunction of

Venus

and the

Sun

on April 25, 1917,

and

ending June29, 1932, w-erearrangedinregularorderintheirrespec-

NO. II

FREQUENCY

OF VISIBLE

SUN

SPOTS

SANFORD

₃

atan angular distance of 90 ^degrees

—

^{andthesun-spot}

^numbers

^for

each of these100 daysaregivenintable2.

Table2.

—

TheEarthand Venusatanangular separationofninetydegrees

Sept.18, July 3, Apr. 2, Feb. 6,

Nov.26, Sept.15, July 2, Apr. 17, Feb. _3, Nov.26,

1917 1918 1919 1920 1920 1921 1922 1923 1924 1924

97

4 SMITHSONIAN MISCELLANEOUS

COLLECTIONS VOL. 95

Takingtheabovefacts intoconsideration alongwiththe

known

dis- turbing influence ofVenus,itseems,ifnot hopeless, yetverydifficult to detectwithcertaintyany effectsof the relativepositions of

Mer-

cury

and

theEarth

upon

thevisiblespottedness of theSun.

Nevertheless, the sun-spottedness of 20periods of 116 days each, starting

from

the inferior conjunction of

Mercury

andtheSun, were addedandtheir

mean

sun-spot

numbers

wererepresented graphically.

The

resultingcurve

was

veryirregularand gave noplain indication of a

marked

sun-spot activity at either conjunction.

However,

in the twenty ii6-dayperiods the sun-spot

numbers

atinferior conjunction averaged 48, and on the 58th day after inferior conjunction they averaged_57,showing anincrease ofabout _{15 percent}

when

theEarth and

Mercury

were onoppositesidesoftheSun.

Itseemsunwiseto laytoo

much

stress

upon

thisonesetof observa- tions.

A

^verylarge

number

of suchseriestakenatwidelydistributed intervals

would

be necessarytodetermine withcertaintythe influence

upon

visiblesunspotsof therelativepositionsof

Mercury and

Earth.

An

attempt

was made

todeterminewhetherthereisanappreciable differenceinsun-spottedness as seen

from

theEarth

when Venus

and

Mercury

areonthesame,or onopposite,sidesof theSun. TAventy-

two

groupsof 5dayseachwere taken

when Venus and Mercury

were at the

same

heliocentric longitude, and the

mean

value of the sun- spot

numbers

for the

no

dayssotaken

was

35.4.

Twenty-three groups of 5 days each, covering the

same

period taken

when

the heliocentriclongitudes of

Venus

and

Mercury

differed by 180 degrees,gavea

mean

value for the sun-spot

numbers

of 44.2 forthe 115 days.

Forty-four groupsof 5days each, covering the

same

period, were taken

when

the heliocentric longitudes of the planets differed by 90 degrees.

The mean

value of the sun-spot

numbers

forthese220days

was

38.5.

The mean

value of theobservedsun-spot

numbers when

the planets were onoppositesidesof the

Sun was

24.9 percent greaterthan

when

they were on the

same

side.

The

observed spottedness

when

the planets wereatan angular separation of

90

^degrees

was

8.8 percent greater than

when

they were on the

same

side of the

Sun

and 12.9 percentlessthan

when

theywere onoppositesidesof theSun.

The

abovedatadonot take intoconsideration therelationofeither planettotheEarth duringtheperiodunderconsideration,anditseems probablethata similarsetofdatatakenatadifferenttime

would show

dift'erentresults. Nevertheless,theyseemsignificantandare given for whateverthey are worth.

XO. II

FREQUENCY

OF VISIBLE

SUN

SPOTS

SANFORD

₅

Similarcomparisonswere

made

with

Mars and

^theEarth

and

with Jupiter and ^the Earth and with the

two

planets taken together. In all casesthe observedeffects were ^virtually inappreciable,being less than 3 percentⁱⁿeverycase.

From

the above data ^it seems safe to assert that sun spots are influencedbythe configurations of

Venus

andtheEarth and probably by

Mercury and

the Earth,

and Mercury and

Venus. In the case ofthe other planetsno sucheffecthasbeen shown.

In the foregoing discussion no attempthas been

made

to propose anytheory of the formationof sunspots. Ithasmerely been

shown

thatsunspots are asifrepelledbytheEarth

and

thenearerplanets.

Any

sun-spot theorymust accountat least forthis effectiverepulsion.

In spiteof the prevailing opinion of astronomersasexpressed by Stratton in "Astronomical Physics " that

enormous

electric fields in and near the

Sun

^"

must

be ruled out," it seems to be universally agreedthatthe rotating gaseswhichgiverisetothepowerful magnetic

fieldsofsunspotsare highlyelectrified.

The

only

known

body which can repelan electricallychargedbody

is anotherbody similarlyelectrified. If the planetswhich are

known

to repel thecharged sun spots are themselveselectrifiedinthe

same manner

asthe repelled sunspots,

we

havea probable explanation of thisrepulsion.

Whether

the planets are so charged or notis a purely qualitative question which cannotbeanswered by any mathematical theory, but onlyinthe

same manner

that

we may

determine theelectrificationof anyinsulatedbody,namely, whetheritrepels orattractsa

known

elec- trifiedbody and whetheritsrotation

may

generate amagneticfield.

The

author has

shown

in his

monograph

on ^"Terrestrial Elec- tricity "^"that the Sun,the Earth,

and

the

Moon

haveallgiven

what

seems to

him

conclusive proofs of their negative electrification. If this shouldbe suspected in the case of the otherplanets, itonly re- mains to inquire

what

other

phenomena

which have been observed betweenelectrifiedbodies

may

be detectedbetween^theplanetsandthe electrifiedgases of theSun.

-Sanford,Fernando, TerrestrialElectricity,Stanford University Press, 1931.