List of days of the year

18 July - Launch of SLV 3 Rocket with Rohini Satellite in 1980

 
SLV-3 , India‘s first Satellite Launch Vehicle , successfully took off from Sriharikota Range (SHAR) in Andhra Pradesh on 18 July, 1980 and lofted 35 kg ROHINI Satellite in near earth orbit. India thus became the seventh member of the exclusive club of nations having their own satellite launch capability.

The main development work of SLV-3 was carried out at the Vikram Sarabhai Space Centre . SHAR Centre of Indian Space Research Organisation (ISRO) was responsible for the launch complex, tracking and telemetry systems, apart from the rocket motors’ propellant processing and their static testing. ISRO Satellite Centre made the Rohini Satellite and the Satellite Application Centre developed the tracking system receiver, telemetry antenna and telecommand Transponder. Major national industries and the Indian institutions contributed to designing, analysis, testing and fabrication of vehicle hardware and heavy structures.

SLV-3 has a length of 22.6 metres and take-off weight of 17 tonnes, and uses four solid propellant stage motors. The first stage is controlled by secondary injection thrust vector and fintip control in sharing mode, the second stage by bi-propellant reaction control system and the third stage by mono-propellant system. The fourth stage along with satellite interface and satellite is spin-stabilised. This fourth stage assembly is protected from aerodynamic heating while in flight by semi-monocoque honeycomb heat-shield.

18 July - The first sound recording in 1877


The first sound recording, and the first of the human voice, that could be heard by contemporaries, was made by Thomas Edison (1847–1931). Although the chronology has frequently been presented in somewhat garbled form (often by Edison himself), the circumstances seem to have been established definitively in Randall Stross's 2007 biography of the inventor. Working late in the lab on 18 July 1877, comparing telephone diaphragms, Edison felt the vibrations as he spoke into one, and voiced his suggestion that, with a point on the diaphragm, it should be possible to make a recording while pulling something beneath it. With the assistance of John Kruesi and Charles Batchelor the experiment was rigged up there and then. Batchelor pulled a strip of wax paper through the device, while Edison spoke the standard phrase the lab used to test telephone diaphragms: "Mary had a little lamb." Playback was indistinct but audible, and by breakfast time the following morning they had achieved clear articulation from the waxed paper. The lab notebook for 18 July includes the brief entry:

Just tried experiment with a diaphragm having an embossing point & held against parafin paper moving rapidly the spkg vibrations are indented nicely & theres no doubt that I shall be able to store up & reproduce automatically at any future time the human voice perfectly

The entry written by Edison is also signed by Batchelor and James Adams, another assistant. It seems clear that Edison himself didn't immediately see the significance of what he had achieved, and it wasn't till 5 November 1877 that he set down on paper his conceptualisation of the tinfoil cylinder phonograph. The first actual working model was built by John Kruesi on 4 December 1877; the sentence "How do you get that?" is said to have been recorded and reproduced by that date. 

18 July - Nadia Elena Comăneci first perfect 10 in 1976


Nadia Elena Comăneci born November 12, 1961 is a Romanian retired gymnast and a five-time Olympic gold medalist, all in individual events. 

On 18 July 1976, Comăneci made history at the Montreal Olympics. During the team compulsory portion of the competition, she was awarded the first perfect 10 in Olympic gymnastics for her routine on the uneven bars.

18 July - Gemini 10 launch in 1966


Gemini 10 was the eighth crewed Earth-orbiting spacecraft of the Gemini series, carrying astronauts John Young and Michael Collins. Its primary purpose was to conduct rendezvous and docking tests with the Agena target vehicle. The mission plan included a rendezvous with the Gemini 8 Agena target, two extravehicular activity (EVA) excursions, and the performance of 15 scientific, technological, and medical experiments. The scientific experiments were related to zodiacal light, synoptic terrain, and synoptic weather photography, micrometeorite collections,  UV astronomical camera, ion wake measurements, and meteoroid erosion.

For many years the spacecraft was the centerpiece of a space exhibition at Norsk Teknisk Museum, Oslo, Norway. It was returned on request in 2002.

The spacecraft is currently on display at the Cosmosphere in Hutchinson, Kansas.