Skylab

Skylab was a space station launched and operated by NASA and was the United States' first space station. Skylab orbited Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a weight of 150,300 pounds (68,175 kg). Three manned missions to the station, conducted between 1973 and 1974 using the Apollo Command/Service Module (CSM) atop the smaller Saturn IB, each delivered a three-astronaut crew. On the last two manned missions, an additional Apollo / Saturn IB stood by ready to rescue the crew in orbit if it was needed.

The station was damaged during launch when the micrometeoroid shield separated from the workshop and tore away, taking one of two main solar panel arrays with it and jamming the other one so that it could not deploy. This deprived Skylab of most of its electrical power, and also removed protection from intense solar heating, threatening to make it unusable. The first crew was able to save it in the first in-space major repair, by deploying a replacement heat shade and freeing the jammed solar panels.

Skylab 3

Skylab 3 (also SL-3 and SLM-2) was the second manned mission to the first American space station, Skylab. The mission began July 28, 1973, with the launch of three astronauts on the Saturn IB rocket, and lasted 59 days, 11 hours and 9 minutes. A total of 1,084.7 astronaut-utilization hours were tallied by the Skylab 3 crew performing scientific experiments in the areas of medical activities, solar observations, Earth resources, and other experiments.

The manned Skylab missions were officially designated Skylab 2, 3, and 4. Mis-communication about the numbering resulted in the mission emblems reading Skylab I, Skylab II, and Skylab 3 respectively.

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Backup crew

Support crew

Mission parameters

Skylab 2

Skylab 2 (also SL-2 and SLM-1) was the first manned mission to Skylab, the first U.S. orbital space station. The mission was launched on a Saturn IB rocket and carried a three-person crew to the station. The name Skylab 2 also refers to the vehicle used for that mission. The Skylab 2 mission established a twenty-eight day record for human spaceflight duration. Furthermore, its crew were the first space station occupants ever to return safely to Earth – the only previous space station occupants, the crew of the 1971 Soyuz 11 mission that had manned the Salyut 1 station for twenty-four days, were killed during reentry.

The manned Skylab missions were officially designated Skylab 2, 3, and 4. Miscommunication about the numbering resulted in the mission emblems reading Skylab I, Skylab II, and Skylab 3 respectively.

Crew

Backup crew

Support crew

Mission parameters

Acids in wine

The acids in wine are an important component in both winemaking and the finished product of wine. They are present in both grapes and wine, having direct influences on the color, balance and taste of the wine as well as the growth and vitality of yeast during fermentation and protecting the wine from bacteria. The measure of the amount of acidity in wine is known as the “titratable acidity” or “total acidity”, which refers to the test that yields the total of all acids present, while strength of acidity is measured according to pH, with most wines having a pH between 2.9 and 3.9. Generally, the lower the pH, the higher the acidity in the wine. However, there is no direct connection between total acidity and pH (it is possible to find wines with a high pH for wine and high acidity). In wine tasting, the term “acidity” refers to the fresh, tart and sour attributes of the wine which are evaluated in relation to how well the acidity balances out the sweetness and bitter components of the wine such as tannins. Three primary acids are found in wine grapes: tartaric, malic and citric acids. During the course of winemaking and in the finished wines, acetic, butyric, lactic and succinic acids can play significant roles. Most of the acids involved with wine are fixed acids with the notable exception of acetic acid, mostly found in vinegar, which is volatile and can contribute to the wine fault known as volatile acidity. Sometimes, additional acids, such as ascorbic, sorbic and sulfurous acids, are used in winemaking.

Acid (disambiguation)

An acid is any chemical compound that, when dissolved in water, gives a solution with a pH less than 7.0.

Acid or ACID may also refer to:

Science

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Music

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Bands

Acid (computer virus)

Acid is a computer virus which infects .COM and .EXE files including command.com. Each time an infected file is executed, Acid infects all of the .EXE files in the current directory. Later, if an infected file is executed, it infects the .COM files in the current directory. Programs infected with Acid will have had the first 792 bytes of the host program overwritten with Acid's own code. There will be no file length increase unless the original host program was smaller than 792 bytes, in which case it will become 792 bytes in length. The program's date and time in the DOS disk directory listing will not be altered.

The following text strings are found in infected files:

External links