Tag Archives: Low Earth Orbit

4 January 1958

Space Flight, , , , , , , ,
Replica of Sputnik 1 satellite at the Smithsonian Institution National Air and Space Museum (NSAM)
Replica of Sputnik 1 satellite at the Smithsonian Institution National Air and Space Museum (NASA)

4 January 1958: After completing 1,440 orbits, Sputnik 1, the world’s first artificial satellite, reentered the Earth’s atmosphere and was destroyed.

Простейший Спутник-1 (Sputnik 1, or Elementary Satellite 1) had been launched 4 October 1957 from Site No. 1 at the Scientific-Research Test Range No. 5, Tyuratam, Kazakh S.S.R. (now, Kazakhstan), aboard a two-stage Sputnik 8K71PS rocket, a variant of the R-7 Semyorka intercontinental ballistic missile.

Mikhail S. Khomyakov
Mikhail S. Khomyakov

The satellite was designed at OKB-1 (the Special Design Bureau) by a team of Mikhail Stepanovich Khomyakov, Maksim Khramov and Oleg Genrikhovich Ivanovsky. It was constructed as a sphere with a diameter of 58.0 centimeters (22.84 inches), made from an aluminum alloy with a thickness of 2 millimeters (0.08 inch). The two halves were joined by 36 bolts and filled with pressurized nitrogen. Four “whip” antennas were equally spaced around the satellite’s shell, angled at 35° from the longitudinal axis. With three silver-zinc batteries and equipment, the Sputnik 1 mass was 83.6 kilograms (184.3 pounds).

The satellite entered an elliptical Low Earth Orbit, with a perigee of 215.0 kilometers (133.6 miles) and apogee of 939.0 kilometers (583.5 miles). The duration of each orbit was 1 hour, 36 minutes, 12 seconds.

An unidentified engineer with Sputnik 1.
An unidentified engineer with Sputnik 1. (OKB-1)

The Sputnik 8K71PS launch vehicle, serial number 1 M1-PS, was a two-stage, liquid-fueled rocket based on the R-7 Semyorka intercontinental ballistic missile. The R-7 rocket was designed by Sergei Pavlovich Korolev, known as The Chief Designer. It had a length of 29.167 meters (95.69 feet) and maximum diameter of 10.3 meters (33.79 feet) at the base, including stabilizers. Its mass was 267.13 tons (588,921 pounds) at liftoff. The propellant was Kerosene T-1 with liquid oxygen.

The first stage consisted of four “strap-on” boosters surrounding the second, of “core” stage, each with an RD-107 four-chamber rocket engine, for a total thrust of 323.6 tons (713,409 pounds) of thrust. The first stage burn time was 120 seconds.

The second stage (core) was powered by one RD-108 four-chamber engine, producing 93 tons (205,028 pounds) of thrust. Burn time for the second stage was 180 seconds.

Sputnik I launch, Site No. 1, Scientific-Research Test Range No. 5, Tyuratam, Kazakh S.S.R., 19:28:34 4 October 1957 UTC (5 October, Tyuratam). (RKK Energiya/Solaris ID 38466)

Sputnik 1 launched at 22:28:34 Moscow time. After 116.38 seconds, the stages separated. The second stage and satellite entered orbit 295.4 seconds after liftoff at an altitude of 228.6 kilometers (142.05 miles) and velocity of 7,780 meters per second (17,403.36 miles per hour). The satellite separated from the second stage 5 minutes, 14.5 seconds after launch.

The second stage reentered the atmosphere 2 December 1957.

© 2019, Bryan R. Swopes

19 November 1999, 22:30 UTC

Space Flight, , , , , , , , , , , , ,
神舟一号飞船 (Shenzhou 1) launch, 19 November 1999. (China National Space Administration)

19 November 1999, 22:30 UTC (20 November, 6:30 a.m., CST): The China National Space Administration ( 国家航天局 ) launched 神舟一號 (Shenzhou 1), an unmanned Project 921-1 spacecraft, from the Jiuquan Satellite Launch Area aboard a 长征二号F火箭, (Changzheng or “Divine Arrow”) two-stage rocket. Shenzhou 1 was placed into a Low Earth Orbit ranging from 195 kilometers (121 miles) to 315 kilometers (196 miles).

The vehicle completed 14 orbits. It successfully deorbited and reentered Earth’s atmosphere. The Shenzhou reentry module landed in Inner Mongolia, 20 November at 19:41 UTC. The duration of the flight was 21 hours, 11 minutes.

The Shenzhou 1 spacecraft was not fully operational and it differed in several ways from the manned space vehicles that followed. The primary purpose of this flight was a test of the man-rated Long March 2F rocket.

The Shenzhou spacecraft is similar to the Russian Federation’s Soyuz from which it was developed, although it is larger. Shenzhou vehicles are 9.25 meters (30 feet, 4.2 inches) long and 2.80 meters (9 feet, 2.2 inches) in diameter. The spacecraft has a mass of 7,840 kilograms (17,284 pounds). There are three modules: the orbital module, reentry module and service module. The vehicle is designed for three people for flights of up to 20 days duration.

An unidentified Shenzhou/Long March 2F launch from the Jiuquan Sateliite Launch Area. (CNSA)

The Changzheng is known as the Long March 2F in the West. It is a two-stage liquid-fueled rocket with external boosters.

The first stage is 23.7 meters (77 feet, 9.6 inches) long with a diameter of 3.35 meters (10 feet, 11.9 inches). It is powered by four YF-20B engines (clustered as a YF-21B unit) which use hypergolic fuels. The four “strap-on” boosters use the same engines. The boosters are 15.6 meters (51 feet, 2.2 inches) long and 2.25 meters (7 feet, 4.6 inches) in diameter. With all eight engines running, the total rated thrust is 1,331,140 pounds (5,921.206 kilonewtons) at Sea Level. The boosters’ burn time is 2 minutes, 8 seconds, while the primary engines burn for 38 seconds longer.

The second stage is 15.52 meters (50 feet, 11 inches) long and the same diameter as the first stage. It uses one YF-24B unit, consisting of one YF-22B and four YF-23B engines. The second stage uses the same hypergolic fuel as the first stage. This stage is rated at 177,240 pounds of thrust (788,403 kilonewtons) at Sea Level and burns for 5 minutes. The Long March 2F is capable of lifting a 8,400 kilograms (18,519 pounds) payload into Low Earth Orbit.

JIUQUAN SLC, INNER MONGOLIA, CHINA-DECEMBER 18, 2012: This December 18, 2012, image provides an overview of JSLC’s South Launch Complex just 11 hours prior to the launch of the G?kt?rk 2, a remote sensing satellite for the Turkish government. In addition to the vertical assembly building, the SLS-1 (921) launch pad and the SLS-2 (603) launch pad, various other support buildings are visible. (Photo DigitalGlobe via Getty Images)
Satellite image of the Jiuquan Satellite Launch Area, Inner Mongolia, 18 December 2012. The vertical assembly building is in the lower half of the photograph, with two launch pads in the upper half.  (Bloomberg/DigitalGlobe via Getty Images)

© 2018, Bryan R. Swopes