He made the first measurement of stellar parallax: 0. 3 arcsec for the binary star 61 Cygni.

61 Cygni is significant because Friedrich Wilhelm Bessel determined its parallax in 1838, the first star to have a known parallax.

Examples of well-known stars which are usually referred to by their Flamsteed numbers include 51 Pegasi ( see Extrasolar planet ), and 61 Cygni ( see Parallax ).

In 1838 Bessel won the race, announcing that 61 Cygni had a parallax of 0. 314 arcseconds ; which, given the diameter of the Earth's orbit, indicated that the star is 10. 4 ly away.

If the currently accepted figure of 11. 4 ly ( see 61 Cygni and discussion page ) is correct, Bessel's figure had an error of 8. 8 %.

As well as helping determine the parallax of 61 Cygni, Bessel's precise measurements allowed him to notice deviations in the motions of Sirius and Procyon, which he deduced must be caused by the gravitational attraction of unseen companions.

The first direct measurement of the distance to a star ( 61 Cygni at 11. 4 light-years ) was made in 1838 by Friedrich Bessel using the parallax technique.

Examples include 61 Cygni and 47 Ursae Majoris.

But Friedrich Bessel was skeptical about Struve's data, and, when Bessel published a parallax of 0. 314 ″ for the star system 61 Cygni, Struve revised his value for Vega's parallax to nearly double the original estimate.

Cygni, 61

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Like Philadelphia's late Dr. Albert C. Barnes who kept his own great collection closed to the general public ( Time, Jan. 2 ), Thompson, at 61, is something of a legend in his own lifetime.

* 1949 – Former First Lady of the Philippines Aurora Quezon, 61, is assassinated while en route to dedicate a hospital in memory of her late husband ; her daughter and 10 others are also killed.

Aveiro ( or ) is a city in Aveiro Municipality in Portugal, with a total area of 199. 9 km², a total population of 78, 463 inhabitants, and 61, 430 electors ( 2006 ).

It is a synthetic element whose most stable known isotope, < sup > 270 </ sup > Bh, has a half-life of 61 seconds.

Having declined from more than one million speakers around 1950 to about 200, 000 in the first decade of the 21st century, of whom 61 % are more than 60 years old, Breton is classified as " severely endangered " by the UNESCO Atlas of the World's Languages in Danger.

In a sense that can be made precise, the probability that two randomly chosen integers are coprime is 6 / π < sup > 2 </ sup > ( see pi ), which is about 61 %.

There are vast timber resources, and commercial development of the country ’ s 61 million hectares ( 150 million acres ) of exploitable wooded area is only beginning.

Its coordinates are 15 25 N, 61 20 W. It is known as " The Nature Island of the Caribbean " due to its spectacular, lush, and varied flora and fauna, which is protected by an extensive natural park system.

The Sinai Peninsula is a triangular-shaped peninsula, about 61, 100 km < sup > 2 </ sup > in area ( slightly smaller than the U. S. state of West Virginia ).

' Amnesty International ' notes that in a country where the average life expectancy is 61 or 62, this means many spend their entire adult lives in the army, frequently facing hard labor and meager wages.

This is equivalent to less than one 730-MB CD-ROM per person in 1986 ( 539 MB per person ), roughly 4 CD-ROM per person of 1993, 12 CD-ROM per person in the year 2000, and almost 61 CD-ROM per person in 2007.

Cayuga is the longest ( 38. 1 miles, 61 km ) and Seneca the largest in total area.

He later opined that the governor-general's role was more than a representative of the sovereign, explaining: " under section 2 of the Constitution the Governor-General is the Queen's representative and exercises certain royal prerogative powers and functions ; under section 61 of the Constitution the Governor-General is the holder of a quite separate and independent office created, not by the Crown, but by the Constitution, and empowered to exercise, in his own right as Governor-General and not as a representative or delegate of the Queen, all the powers and functions of Australia's head of state.

In the December 23, 1980 strip, Jon states that he is 30 years old ( meaning he is 61 years old as of January 2012, although he has not aged physically ).

The most visited region is Budapest, the Hungarian capital attracted 3, 61 million visitors in 2008.

Life expectancy is 61 years in Haiti, 73. 7 years in the Dominican Republic.

In addition, among EU states, the Italian language is most likely to be learned as a second language in Malta by 61 % of the population, as well as in Slovenia by 15 % of the population, in Croatia by 14 % of the population, Austria by 11 % of the population, Romania by 8 % of the population, and by France and Greece by 6 % of the population.