SMDC History: Jupiter-C launches Army's space mission

By Sharon Watkins Lang (SMDC/ARSTRAT)January 29, 2018

Explorer 1
Although the Jupiter C successfully launched at 10:48 P.M. EST, it was not until the early hours of Feb. 1 that officials could confirm that the satellite was on orbit and communicating with stations on Earth. After monitoring the launch from the Pen... (Photo Credit: U.S. Army) VIEW ORIGINAL

On Jan. 31, 1958, the U.S. Army made history when at 10:48 p.m. EST, the Army Ballistic Missile Agency launched a Jupiter C rocket from Cape Canaveral, Florida, carrying America's first satellite.

This in itself was not remarkable. The rocket had already flown in successful test flights, but this flight was different. This flight put the United States into the space race with the launch of Satellite 1958 Alpha, more commonly known as Explorer I.

Three months earlier, on Oct. 4, 1957, the Soviet Union had put the first artificial earth satellite, Sputnik I, into orbit. One month later, on Nov. 3, the Soviets sent another satellite into orbit, this one with a passenger -- a dog named Laika.

The race to space began with a July 1955 announcement by President Eisenhower's Press Secretary James Hagerty. Speaking from the White House, Hagerty announced that the United States would launch "small Earth-circling satellites" as part of the American participation in the International Geophysical Year. The services responded immediately with three proposals.

In keeping with the president's "Open Skies" policy, the Naval Research Laboratory headed the project. Based upon a Navy sounding rocket, the Vanguard required substantial modifications to the first and second section and the development of a new third stage to deploy a satellite. Although preliminary tests had proved promising, the first complete Vanguard test, televised live on Dec. 6, 1957, exploded seconds after lift-off destroying both the rocket and the launch pad.

In the interim, on Oct. 4, 1957, Secretary of Defense designate Neil McElroy was at Redstone Arsenal for an inspection visit of the Army's rocket and guided missile capabilities. That evening, with the news of the Sputnik launch, Dr. Wernher von Braun, director of the Development Operations Division, announced "Sir, when you get back to Washington you'll find that all hell has broken loose." He added that the ABMA could launch an American satellite within 60 days of receiving the green light to proceed. Maj. Gen. John B. Medaris, ABMA commander, concurred only modifying the time span to 90 days.

Their argument was reinforced by Secretary of the Army Wilbur Brucker in a subsequent letter to McElroy. Brucker noted "The first Jupiter C attained an altitude of 650 miles and a range of over 3,300 miles. We have already proven the three most difficult stages of a four-stage satellite vehicle."

However, it was not until Nov. 8, five days after the launch of Sputnik II, that McElroy ordered the Army to modify two Jupiter-C missiles and attempt to place a satellite in orbit by March 1958.

Thanks to von Braun's "silent coordination" with Dr. William Pickering of the Joint Propulsion Lab and Dr. James van Allen of the University of Iowa in the months prior to this decision, just 84 days later, the Army was ready to go. Firing calculations were finalized and modifications made to the Jupiter-C and its satellite payload were completed.

The ABMA, located on Redstone Arsenal, Alabama, focused upon the necessary modifications to the Jupiter C and its propulsion system, a project that involved all nine labs of the ABMA. The fourth stage of the rocket and the Explorer I itself were designed by the ABMA/California Institute of Technology's Jet Propulsion Lab, under the direction of Pickering.

The specially designed Explorer I measured 80 inches long and weighed only 30.66 pounds of which 18.35 pounds were instruments. Developed and constructed by van Allen, the scientific instrumentation included Geiger counters, internal and external temperature gauges, a micrometeorite impact microphone and a series of micrometeorite erosion gauges.

The weather however proved difficult. The countdown at Launch Pad 26 at Cape Canaveral began Jan. 29 but was halted by Medaris, due to high winds. On the next day, the launch was postponed again, just before the liquid oxygen was added to the rocket, due to gales in the upper atmosphere. Then, on Jan. 31 the launch go-ahead was given and the Army achieved another first when Explorer I was launched into space.

In a 1978 interview, on the 30th anniversary of the launch, Medaris recalled the tensions of the moment. "I felt, as the thing was going up, on the thin thread of that satellite hangs the fate of the free world."

With news of the launch, celebrations began in Huntsville, where a parade to celebrate the second anniversary of the ABMA was scheduled for the next day. Elsewhere however, the tensions would continue for hours as scientists and radio operators waited for the first signal from Explorer I.

It was only later as Medaris received the message "Goldstone has the bird." that they could confirm that the satellite was in orbit. The formal announcement, however, came from the White House as President Eisenhower, monitoring the launch from August, Georgia, officially announced at 1 a.m. EST that the United States had successfully placed a satellite in orbit. In a 2 a.m. news conference, the Jupiter-C/Explorer I team represented by Pickering, van Allen, and von Braun hosted a press conference to an enthusiastic room of reporters eager for news of the event.

Congratulatory telegrams and notes poured into the ABMA headquarters. In many respects, the sentiments and pride of the American public and military community may best be summed up in the telegram from the commandant of the U.S. Army Infantry School at Fort Benning, Georgia. His telegram gave the ABMA headquarters full and free use of their motto -- "Follow Me."

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