Prospero (satellite)

The Prospero satellite, also known as the X-3, was launched by the United Kingdom in 1971. It was designed to undertake a series of experiments to study the effects of space environment on communications satellites and remained operational until 1973, after which it was contacted annually for over twenty-five years. Although Prospero was the first British satellite to have been launched successfully by a British rocket, the first British satellite placed in orbit was Ariel 1, launched in April 1962 on an American rocket.

Prospero has the COSPAR (NSSC ID) designation 1971-093A and the US Space Command satellite catalogue number 05580.

Construction

Prospero was built by the Royal Aircraft Establishment in Farnborough. Initially called Puck, it was designed to conduct experiments to test the technologies necessary for communication satellites, such as solar cells, telemetry and power systems. It also carried a micrometeoroid detector, to measure the presence of very small particles. When the Ministry of Defence cancelled the Black Arrow programme, the development team decided to continue with the project, but renamed the satellite Prospero when it was announced it would be the last launch attempt using a British rocket. An earlier Black Arrow launch, carrying the Orba X-2 satellite, had failed to achieve orbit after a premature second-stage shut down.

Prospero

Prospero (/ˈprɒspəroʊ/ PROS-pər-oh) is a fictional character and the protagonist of William Shakespeare's play The Tempest.

The Tempest

Prospero is the rightful Duke of Milan, whose usurping brother, Antonio, had put him (with his then three-year old daughter, Miranda) to sea on "a rotten carcass of a butt [boat]" to die, 12 years before the play begins. Prospero and Miranda survived and found exile on a small island. He has learned sorcery from books, and uses it while on the island to protect Miranda and control the other characters. Before the play has begun, Prospero frees Ariel from entrapment within "a cloven pine", about which Prospero states:

When I arrived and heard thee, that made gape

The pine and let thee out.

Prospero's sorcery is sufficiently powerful to control Ariel and other spirits, as well as to alter weather and even raise the dead: "Graves at my command have waked their sleepers, oped, and let 'em forth, by my so potent Art."- Act V, scene 1.

On the island, Prospero becomes master of the monster Caliban (the son of Sycorax, a malevolent witch) and forces Caliban into submission by punishing him with magic if he does not obey, and of Ariel, a spirit who is beholden to Prospero after he is freed from his imprisonment inside the pine tree.

Prospero (moon)

Prospero (/ˈprɒspəroʊ/ PROS-pər-oh) is a relatively small retrograde irregular satellite of Uranus discovered on 18 July 1999 by the astrophysicist Matthew Holman and his team, and given the provisional designation S/1999 U 3. Confirmed as Uranus XVIII it was named after the sorcerer Prospero in William Shakespeare's play The Tempest.

The orbital parameters suggest that it may belong to the same dynamic cluster as Sycorax and Setebos, suggesting common origin. However, this suggestion does not appear to be supported by the observed colours. The satellite appears neutral (grey) in visible light (colour indices B-V=0.80, R-V=0.39), similar to Setebos but different from Sycorax (which is light red).

See also

References

Prospero (plant)

Prospero is a genus of bulbous flowering plants in the family Asparagaceae, subfamily Scilloideae (also treated as the family Hyacinthaceae). It is distributed in Europe, around the Mediterranean, and through the Middle East to the Caucasus.

Description

Species of Prospero grow from bulbs, the leaves and flowers appearing in the autumn and dying down in spring. The leaves are relatively narrow. Each bulb produces one to four flowering stems (scapes) bearing dense racemes of pink to violet flowers. The 4–10 mm (0.2–0.4 in) long tepals are not joined together. The stamens have filaments coloured like the tepals and short purple anthers. The dark brown seeds are more-or-less oblong.

Systematics

The genus Prospero was created by Richard Salisbury in 1866. However, some species he placed in the genus, such as P. hyacinthoideum and P. lingulatum, are currently placed in other genera.Franz Speta and co-workers from the 1970s onwards split up the broadly defined genus Scilla, placing many species into separate genera. The modern understanding of Prospero dates from 1982, with Speta's re-assignment of Scilla autumnalis (among other species) to Prospero.

X.3

X.3 is an ITU-T standard indicating what functions are to be performed by a Packet Assembler/Disassembler (PAD) when connecting character-mode data terminal equipment (DTE), such as a computer terminal, to a packet switched network such as an X.25 network, and specifying the parameters that control this operation.

The following is list of X.3 parameters associated with a PAD:

References

External links

X3

X3 may refer to:

Films, books, games and music

Transportation and technology

Excess-3

Excess-3 or 3-Excessbinary code (often abbreviated as XS-3 or X3) or Stibitz code (after George Stibitz) is a complementary BCD code and numeral system. It also constitutes a biased representation. Excess-3 was used on some older computers as well as in cash registers and hand held portable electronic calculators of the 1970s, among other uses. It is a way to represent values with a balanced number of positive and negative numbers using a pre-specified number N as a biasing value. It is a nonweighted code. In XS-3, numbers are represented as decimal digits, and each digit is represented by four bits as the digit value plus 3 (the "excess" amount):

To encode a number such as 127, then, one simply encodes each of the decimal digits as above, giving (0100, 0101, 1010).

Adding Excess-3 works on a different algorithm than non-biased decimal coding or regular binary positional system numbers. When you add two XS-3 numbers together, the result is not an XS-3 number. For instance, when you add 1 and 0 in XS-3 the answer seems to be 4 instead of 1. In order to correct this problem, when you are finished adding each digit, you have to remove the extra bias by subtracting binary 0011 (decimal 3 in unbiased binary) if the resulting digit is less than decimal 10 and subtracting binary 1101 (decimal 13 in unbiased binary), if an overflow has occurred. Note that, in 4-bit binary, subtracting binary 1101 is equivalent to adding 0011 and vice versa.