Evening star. [volume] (Washington, D.C.) 1854-1972, 1959-03-05
Pioneer " Swings Into Solar Orbit,
Expected to Retroce Its Path Forever
BY WILLIAM HINES
star Science Writer

star Science Writer
The United States space
probe Pioneer w was firmly in
orbit around the sun today,
with q probable lifetime com
parable to the life expectancy
Of our universe"
Announcement Of Pioneers
attainm n t Of independent
planetoid status came late yes
terday afternoon at news con-
ference at the National Aero
nautics and Space Agency.
NASA and the Army had fired
the l3la-pound Instrumental
cone into space atop a June II
four-stage rocket at Cape Ca
naveral, Fla, at 1911 am.
Tuesday.
Just over IL hours later-at
5:24 pm. yesterday-the space
probe passed the orbit Of the
moon and swung into orbit
around the sun. At the moment
of closest approach, Pioneer
was $1,000, miles from the
moon, slightly over degrees
ahead of it and about 5la de-
grees to the south. 1t was going
4,525 miles an hour.
Closest to Sun March II
DR.. Homer j. Stewart. direc-
tor of program planning and
evaluation for NASA, gave this
description of Pioneers eternal
circuit around the sun:
It will swing to perihelion-
closest approach to the sun
on March II, when it will be
about l,l68, 900 miles inside the
earth's orbit and about 9l.7
million miles from the sun.
Aphelion. or farthest retreat
from the sun. will come Sep
TENDER 20. when the tiny
planetoid will be 1858 million
miles distant, nearly Is million
miles farther out than the
earth.
It will retrace this path for
ever-barring an unforeseeable
cosmic collision-making one
rotation every 1872 days. Be-
cause Pioneers year" is nearly
q month longer than the
earth's, the likelihood of the
mother planet and its offspring
ever colliding is extremely
remote.
President Gratified
President Eisenhower. asked ,
about the Pioneer launching at
his press conference yesterday, |
expressed qualification
II have been talking to the
scientists about this" Mr.. Ell
senhower said, land of course
I was highly pleased that the
test came Of as they planned.
AS you know, they did not plan
to orbit the moon. Actually, my
latest information. as ! came
in here. that the thing was
exactly 100000 miles from us
as we started this talk here,
but it was going-it's going
past the moon think on the
order of about $1,000. PLUS or
minus two. plus or minus 1000,
1t will be DRIFTING around the
sun and its signals. the signals
it has transmitted have been
most interesting to our SCI
entiSts and particularly in Civ
ing additional information on
this belt of radioactivity that !
has been discovered around the
world, around the earth, and is
Of such tremendous interest to
our scientists"
No New Data
The belt OF radioactivity"
referred to by the President is
the so-called Van Allen belt,
discovered last year by inStru-
ments aboard two Explorer
earth satellites. The inStru-
ments, modified Geiger coun-
tiers, were devised by a State
University of Iowa group
headed by physicist James A.
Van Allen. (
On the basis of early infor-
nation from Pioneer ", DR.. I
Van Allen told NASA yesterday /
that nothing new of significance (
had been learned from the two
Geigers aboard the space probe. /
One of the counters had been
shielded with a sixth of an inch |
Of lead to give a count of
strongly radioactive particles
only.
Internal Temperature 11l'F
Signals from the Geigers and
from a temperature recording
device were being sent earth
ward by a tiny radio trans
mitter using only 10 hundredths
Of a watt of power. A salts
factory" internal temperature
of Ill degrees F was being
maintained, DR.. Stewart re-
ported.
Batteries towering the radio
had a designed life of 80 hours.
II all goes according to schedule,
STEllART A0Tf