Besides the well-known hydrogen line at 21 cm wavelength, the spectra of extraterrestrial radio sources may contain sharp lines characteristic of other atoms, ions, and small molecules.

Radio observations revealed a sharp increase in continuum emission at a wavelength of 21 cm after the largest impacts, which peaked at 120 % of the normal emission from the planet.

The Sleep of Reason Produces Monsters, c. 1797, 21. 5 cm × 15 cm.

In 1944, Hendrik van de Hulst predicted microwave radiation at a wavelength of 21 cm resulting from interstellar atomic hydrogen gas ; this radiation was observed in 1951.

Radio telescopes can also be used to observe neutral hydrogen ( via 21 cm radiation ), including, potentially, the non-ionized matter in the early universe that later collapsed to form galaxies.

They are detected primarily in the 21 cm line of neutral hydrogen, and typically have a lower portion of heavy elements than is normal for interstellar clouds in the Milky Way.

Main armament was eight 21 cm guns, but with six 15 cm and eighteen 8. 8 cm guns for smaller targets.

Four battleships of the Helgoland class were laid down in 1909 – 1910, with displacements of 22, 800 tons, twelve 30. 5 cm guns in 6 turrets, reciprocating engines generating a maximum speed of 21 knots, and a price tag of 46 million GM.

A skeet shooter, shooting at close targets might use 127 micrometres ( 0. 005 inches ) of constriction to produce a 76 cm ( 30 inch ) diameter pattern at a distance of 19 m ( 21 yards ).

Scorpions range in size from 9 mm ( Typhlochactas mitchelli ) to 21 cm ( Hadogenes troglodytes ).

Epsilon Telescopii A is an orange giant of spectral type K0III with an apparent magnitude of + 4. 52, with a 13th magnitude companion, Epsilon Telescopii B, 21 arcseconds away from the primary, and just visible with a 15 cm telescope on a dark night.

File: Lvr-george. jpg | Saint George and the Dragon, a small work ( 29 x 21 cm ) for the court of Urbino.

They measure 13 – 37 inches ( 35 – 94 cm ) long from their snout to the base of the tail, with the tail adding another 8. 5 – 19 inches ( 21. 6 – 47 cm ).

In 2007, Khatri and Wandelt of the University of Illinois at Urbana-Champaign realized that the 21 cm hyperfine transition in neutral hydrogen of the early Universe leaves a unique absorption line imprint in the cosmic microwave background radiation.

* 1944 — Hendrik van de Hulst predicts the 21 cm hyperfine line of neutral interstellar hydrogen

* 1951 — Harold I. Ewen and Edward Purcell observe the 21 cm hyperfine line of neutral interstellar hydrogen

Each card was wound with two layers of enameled nickel alloy wire with a diameter of 17 µm ( 21 µm with the enamel insulation included ) in such way that a total area of 1 cm by 1 cm was completely covered.

File: Picabia SelfDrawing. JPG | Self-Portrait, c. 1923, ink on paper, 25 × 21 cm, private collection

The most rainfall in a month was 26. 95 inches ( 68. 45 cm ) in February 1986 and the most in 24 hours was 11. 56 inches ( 27. 74 cm ) on January 21, 1967.

| archivedate = February 21, 2008

For example, 21 is the GCD of 252 and 105 ( 252 = 12 × 21 ; 105 = 5 × 21 ); since 252 − 105 = ( 12 − 5 ) × 21 = 147, the GCD of 147 and 105 is also 21.

By reversing the steps in the Euclidean algorithm, the GCD can be expressed as a sum of the two original numbers each multiplied by a positive or negative integer, e. g., 21 = × 105 + × 252.

: 147 = 7 × 21 + 0.

| climb rate alt = 21. 5 m / s

| DATE OF DEATH = November 21, 1997

It was stated earlier that one purpose of this study was to extend the analysis of variability of Onset and Completion in each of the 21 growth centers somewhat beyond that provided by the data in Tables 1 and 2.

The numbering system used in Tables 1 and 2 and Figures 1 and 2 was continued for the 21 growth centers.

In 1960, David D. Thomas published Basic Vocabulary In some Mon-Khmer Languages ( AL 2, No. 3, pp. 7 - 11 ), which compares 8 Mon-Khmer languages with the I-E language data on which Swadesh based the revised retention rate ( Af ) in place of original ( Af ), and his revised 100 word basic glottochronological list in Towards Greater Accuracy ( IJAL 21::

Mount Melbourne ( 2, 730 m ) ( 74 ° 21 ' S., 164 ° 42 ' E.

" Journal of Contemporary History 1986 21 ( 2 ): 209 – 224.

* Apollodorus, Epitome III, 32 – IV, 2 ; V, 21 ;

The Lunar Module Orion, with Young and Duke inside, landed north and west of the planned landing site at 104 hours, 29 minutes, and 35 seconds into the mission, at 2: 23: 35 UTC on 21 April.

Many who side with this view disagree that Luke portrays Christianity or the Roman Empire as harmless and thus reject the apologetic view because “ Acts does not present Christians as politically harmless or law abiding for there are a large number of public controversies concerning Christianity, particularly featuring Paul .” For example, to support this view Cassidy references how Paul is accused of going against the Emperor because he is “ saying that there is another king named Jesus .” ( Acts 17: 7 ) Furthermore, there are multiple examples of Paul ’ s preaching causing uprisings in various cities ( Acts 14: 2 ; 14: 19 ; 16: 19-23 ; 17: 5 ; 17: 13-14 ; 19: 28-40 ; 21: 27 ).

Here Acts 12: 21-23 is largely parallel to Antiquities 19. 8. 2 ; ( 2 ) the cause of the Egyptian pseudo-prophet in Acts 21: 37f and in Josephus ( War 2. 13. 5 ; Antiquities 20. 8. 6 ); ( 3 ) the curious resemblance as to the order in which Theudas and Judas of Galilee are referred to in both ( Acts 5: 36f ; Antiquities 20. 5. 1 ).

He married fourthly at the Dolmabahçe Palace, Constantinople, on 21 September 1866 to Georgian HH Hayranidil Kadın Efendi ( Kars, 2 November 1846 – Ortaköy Palace, Constantinople, 26 November 1898 ), and had two children.

* Folio 23 verso: Weasel ( Mustela ) ( Isidore of Seville, Etymologiae, Book XII, iii, 2 ; Physiologus, Chapter 21 )

By 2003 in the US, an estimated 3. 21 million patients received antipsychotics, worth an estimated $ 2. 82 billion.

Fairbanks receives an average 21 hours of daylight between May 10 and August 2 each summer, and an average of less than four hours of daylight between November 18 and January 24 each winter.

The legend is linked to an idea in the Book of Revelation ( 3: 12 and 21: 2 ) describing a Second Coming, wherein Jesus establishes a new Jerusalem.

Following rehearsals in New York City, the company started pre-Broadway tryouts in Philadelphia from March 2 to 21, 1964.

Geographical coordinates: 53 ° 46 ' 0 " North, 2 ° 21 ' 0 " West.

The average household size was 2. 67 and the average family size was 3. 21.

21. 9 % ( male 2, 401 ; female 2, 358 )

In 1990, Bulgaria had a total of more than 2, 400 tanks, 2, 000 armored vehicles, 2, 500 large caliber artillery systems, 300 fighter and bomber aircraft, 100 trainer aircraft, more than 40 combat and 40 transport helicopters, 4 submarine, 6 fast missile craft, 2 frigates, 5 corvettes, 6 torpedo boats, 9 patrol craft, 30 minesweepers and 21 transport vessels.