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... what are centaurs?

In astronomical terms, centaurs are a class of small celestial bodies, sharing characteristics of both asteroids and comets. Located in the outer regions of our Solar System, between the orbits of Jupiter and Neptune, they are similar to asteroids in size, but more like comets in composition. Whereas asteroids are made up primarily of rocky material, comets are composed mostly of ice and volatile materials which vaporize as comets approach the Sun. Likewise centaurs are icy bodies. A few, such as 60558 Echeclus, are known to display comet-like comas. However, most centaurs do not exhibit such activity since they orbit too far from the Sun.

It is speculated that centaurs are objects from the Kuiper Belt which have been drawn into the Solar System by the gravitational attraction of the giant planets. Consequently their orbits are eccentric and unstable. It is estimated there are some 44,000 centaurs with diameters greater than 1km. The first object to be designated a centaur was 2060 Chiron in 1977, followed by 5145 Pholus in 1992.

944 Hidalgo, discovered in 1920 and originally listed as an asteroid, is now classified as a centaur.

Asteroid Field

... what the Universe sounds like?

Click here to find out.


... how big our Solar System is?

Click on the rocket to begin your interactive journey.

... how big the Milky Way is?

Our home galaxy is approximately 100,000 light-years in diameter, and 10,000 light-years deep at its core.

One light-year is equal to the distance light travels in the vacuum of space in one year, that is 9.46 trillion kilometers, or 5.88 trillion miles.

The Milky Way - Photo by Larry Landolfi

Photo credit: Larry Landolfi & APOD

... a non-planetary body with its own moon?

Asteroid 243 Ida (pronounced 'Eye-da') was discovered by the Austrian astronomer, Johann Palisa, on September 29, 1884. Located in the Asteroid Belt between the orbits of Mars and Jupiter, Ida became the second asteriod to be visited by a spacecraft when NASA's Galileo probe passed close by on its way to Jupiter on August 28, 1993. From this fly-by, Ida became the first asteroid known to have a moon, now named Dactyl. Ida is 30km (or 19 mi) in diameter, while tiny Dactyl is only 1.6km (or 1 mile) across.

Asteroid 243 Ida and Dactyl, its moon

... the world's largest fully steerable telescope?

The Robert C. Byrd Green Bank Telescope in West Virginia, USA, is the largest fully steerable telescope in the world. Its large parabolic dish measures 100 metres by 110 metres, with a total collecting area of 2.3 acres. It is the largest collecting area of any fully steerable telescope in the world. 7,652 beams are needed to support the dish on top of its almost hemispherical tilting gear. A gigantic yoke cradles the gear above a base of concrete sunk 25 feet down to solid bedrock. It has a 200-foot feed arm which sticks out of the side of the dish and ends in a secondary mirror hanging some 60 feet above. The secondary mirror is used to aim the dish’s focused radio waves into eight receivers located in a rotating turret. If necessary, a ninth receiver on a boom bar can be swung into place instead of the secondary mirror. From its base to the top of its huge feed arm, the telescope stands 485 feet tall, and weighs over 17 million pounds. Four four-wheeled trucks are used to move the telescope around its 360-degree concrete track, making the GBT the largest moving object on land. Over the course of a year, it can survey 85% of the skies surrounding the Earth, and is used by astronomers from around the world for 6500 hours each year.

Green Bank Telescope

... the difinition of Astrobiology?

Astrobiology is "the science that studies the origin and evolution of life in the universe; the effects of extraterrestrial conditions on living organisms from Earth; the potential existence of life beyond the Earth's atmosphere; and the prospects for the future of life on Earth and beyond." Webster's College Dictionary

To discover more about Astrobiology, click this link:

Astrobiologists are studying extreme environments on Earth to understand how and where life may evolve in similar environments in our Solar System and beyond.

One such environment is in Spain, in the very acidic Rio Tinto where aerobic bacteria thrive. Here in the Caribbean, astrobiologists are studying Trinidad's Pitch Lake.

Rio Tinto in Spain

... who is the parton saint of Astronomy?

The patron saint of Astronomy and astronomers is St. Dominic de Guzman. Born in Caleruega, Spain, in 1170, St. Dominic was the founder of the Order of Preachers, more commonly known as the Dominican Order. He died in 1221 and was canonized on July 13th, 1234. His feast day is August 8th.

... who is the parton saint of astronauts?

Joseph of Cupertino (1603 - 1663), an Italian Franciscan friar and Christian mystic who was canonized in 1763, is the patron saint of air travellers, aviators and astronauts. He is said to have been prone to ecstatic visions and instances of miraculous levitation.