Epsilon (uppercase Ε, lowercase ε or lunate ϵ; Greek: Έψιλον) is the fifth letter of the Greek alphabet, corresponding phonetically to a close-mid front unrounded vowel /e/. In the system of Greek numerals it has the value five. It was derived from the Phoenician letter He . Letters that arose from epsilon include the Roman E, Ë and Ɛ, and Cyrillic Е, È, Ё, Є and Э.
The name of the letter was originally εἶ (Ancient Greek: [êː]), but the name was changed to ἒ ψιλόν (e psilon "simple e") in the Middle Ages to distinguish the letter from the digraph αι, a former diphthong that had come to be pronounced the same as epsilon.
In essence, the uppercase form of epsilon looks identical to Latin E. The lowercase version has two typographical variants, both inherited from medieval Greek handwriting. One, the most common in modern typography and inherited from medieval minuscule, looks like a reversed "3". The other, also known as lunate or uncial epsilon and inherited from earlier uncial writing, looks like a semicircle crossed by a horizontal bar. While in normal typography these are just alternative font variants, they may have different meanings as mathematical symbols. Computer systems therefore offer distinct encodings for them. In Unicode, the character U+03F5 "Greek lunate epsilon symbol" (ϵ) is provided specifically for the lunate form. In TeX, \epsilon
() denotes the lunate form, while
\varepsilon
() denotes the inverted-3 form.
The Epsilon rocket (イプシロンロケット, Ipushiron roketto) (formerly Advanced Solid Rocket) is a Japanese solid-fuel rocket designed to launch scientific satellites. It is a follow-on project to the larger and more expensive M-V rocket which was retired in 2006. The Japan Aerospace Exploration Agency (JAXA) began developing the Epsilon in 2007. It is designed to be capable of placing a 1.2 tonne payload into low Earth orbit.
The development aim is to reduce costs compared to the US$70 million launch cost of an M-V. The Epsilon costs US$38 million (£23m) per launch, which is half the cost of its predecessor. Development expenditures by JAXA exceeded US$200 million.
To reduce the cost per launch the Epsilon uses the existing SRB-A3 as a solid rocket booster on the H-IIA rocket as its first stage. Existing M-V upper stages will be used for the second and third stages, with an optional fourth stage available for launches to higher orbits. The J-1 rocket, which was developed during the 1990s, but abandoned after just one launch, used a similar design concept, with an H-II booster and Mu-3S-II upper stages.
Epsilon is the fifth studio album by Finnish power metal band Dreamtale. Released on The Secret Door record label on 11 May 2011 in Finland, with an earlier 20 April 2011 release in Japan, it reached number 39 on Suomen virallinen lista, The Official Finnish Charts.
Crater may refer to:
In landforms:
Other:
Crater (/ˈkreɪtər/; Arabic: كريتر, [ˈkɾeːtəɾ]), also Kraytar, is a district of the Aden Governorate, Yemen. Its official name is Seera (Arabic: صيرة Ṣīrah). It is situated in a crater of an ancient volcano which forms the Shamsan Mountains. In 1991, the population was 70,319. As of 2003, the district had a population of 76,723 people.
In the closing days of British rule in 1967, Crater District became the focus of the Aden Emergency, sometimes called the last imperial war. After a mutiny of hundreds of soldiers in the South Arabian Federation Army on 20 June, all British forces withdrew from the Crater. The Crater was occupied by Arab fighters while British forces blocked off its two main entrances. In July, a British infantry battalion, led by Lt. Col. Colin Mitchell of the Argyll & Sutherland Highlanders, entered the Crater and managed to occupy the entire district overnight with no casualties. Nevertheless, deadly guerrilla attacks soon resumed, with the British leaving Aden by the end of November 1967, earlier than had been planned by British Prime Minister Harold Wilson and without an agreement on the succeeding governance.
Crater is a constellation. Its name is Latin for cup, and in Greek mythology it is identified with the cup of the god Apollo. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations. It is faint, with no star brighter than third magnitude.
Alpha Crateris, traditionally called Alkes, is an orange-hued giant star of magnitude 4.1, 174 light-years from Earth. Its traditional name means "the cup". Beta Crateris is a blue-white hued star of magnitude 4.5, 266 light-years from Earth. Gamma Crateris is a double star divisible in small amateur telescopes. The primary is a white star of magnitude 4.1, 84 light-years from Earth. The secondary is of magnitude 9.6. Delta Crateris is the brightest star in Crater at magnitude 3.6. 195 light-years away, it is an orange-hued giant star.
R Crateris is a semi-regular variable of type SRb and a spectral classification of M7. It has a magnitude of 9.8-11.2 and an optical period of 160 days.