Brightest Star In The
Galaxy
The Pistol star was discovered by the Hubble
telescope, and is ten million times more powerful than the Sun, yet it can't
be seen by the naked eye as most of the light it gives off is absorbed by
space dust. Astronomers calculate that it emits as much energy in six
seconds as the sun does in a year. While this makes it the most powerful
star yet identified, it also suggests that it will shortly burn itself out.
Pistol is thought to be between one and three million years old, whereas the
sun is five billion, and expected to last another five billion. The star has
been an unknown quantity since first spotted in the early 1990s by
astronomers in South Africa and Japan. Astronomers estimate that it is
25,000 light years away from Earth, towards the centre of the galaxy, and up
to 280 million miles across.
Closet Galaxy to the Milky Way
The closet object to Earth that is not in our
galaxy is the Sagittarius Dwarf Elliptical Galaxy - a huge collection of
stars and clouds made of dust and gas, which is about 82,000 light years
away. The discovery by R.A Ibata G. Gilmore and M.J. Irwin [all UK] was
announced in April 1994
Smallest Constellation
The smallest constellation is Crux Australis
(Southern Cross), with an area of only 0.16% of the sky. It covers 68.477
square degrees. Its distinctive shape is included in the national flag of
Australia. This constellation can only be seen from the southern hemisphere
of the Earth.
Largest Constellation
The largest constellation is Hydra, the "Sea
Serpent". It covers an area of 1,302.844 sq degrees, or 3.16% of the whole
sky, and contains at least 68 stars visible to the naked eye.
Most Luminous Object
Quasar APM08279+5255, the most luminous object
in the universe, was discovered in March, 1998, in the constellation of
Sagittarius. It is estimated to be between 4 and 5 million billion times
brighter than the Sun.
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Brightest Star Seen from Earth
Sirius A [Alpha Canis Majoris], or the Dog Star, is
8.64 light years away from Earth and is the brightest star visible in the
night sky. A 'light year' is the distance that light travels in a year -
roughly 6 trillion miles. The distance between the Earth and Sirius is
approximately 50 trillion miles. Sirius has a mass 2.14 times that of
the Sun, and is visually 24 times more luminous. It is also almost twice as
hot, with a surface temperature of about 17,500 oF
Youngest Pulsar
A team of astronomers at Columbia University, led
by Dr. Eric Gottheff [USA], discovered the youngest pulsar in 1995. The
superdense stellar, called PSR J1846-0258 is located on the other side of
our Milky Way galaxy, about 60,000 light years away, and is only 700 years
old.
Coldest Place In The Universe
The Boomerang Nebula is a cosmic refrigerator
with a mind-numbing temperature of -272°C (-521.6°F). Pack your thermals -
it's officially the coldest place in the universe! The freezing cold spot is
made from a dust and gas cloud thrown off by a dying star, which astronomers
call a "white dwarf". It's so cold because the center of the Nebula is
forced to expand further and faster, as the dying planet sheds more and more
cosmic junk. Deep space decay, however, also leads to cosmic regeneration.
The dust and gas thrown out at the center of the nebula will eventually
collect and merge to form new planets and solar systems like our own.
The Most Massive Extrasolar Planet
The discovery of the massive planet HD168443
orbiting a star 123 light years away was announced in Jan 2001. Jupiter ,
the largest planet in our Solar System, weighs more than all of the other
planets and moons combined. HD 168443 is 17 times more massive even than
Jupiter.
Largest Lunar Impact Basin
The largest impact basin on the Moon is the
far-side South Pole-Aitken, which is 2250 km (1400 miles) in diameter and an
average 12,000 m. (39,000 ft) deep. This is the largest and deepest such
crater known in the Solar System.
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Nearest Star (Excluding
The Sun)
Excepting the special case of our own Sun, the
nearest star to Earth is the very faint Proxima Centauri, discovered in
1915, which is 4.23 light years away. Proxima Centauri is also called Alpha
Centauri C. The star cannot be seen without a telescope.
Fastest Pulsar Spin Rate
Pulsars are the rapidly spinning collapsed cores of
massive stars that have blown themselves apart in a supernova. .Spherical
in shape and the size of a small city, a pulsar is so dense that a
teaspoonful would weigh billion tonnes. For pulsars whose spin rates have
been accurately measured, the fastest-spinning is PSR B1937+214, which was
discovered by a group led by Donald C. Baker [USA] in Nov 1982. It is in the
minor constellation Vulpecula [Little Fox] 11,700 light years distant and
has a pulse period of 1.5578064949 milliseconds which is equivalent to a
spin rate of 641.9282518 revolutions per second.
Nearest Black Hole
The closest black hole is only 1,600 light
years from Earth and is known as V4641 Sgr. It was discovered in January
2000 by astronomers at Massachusetts Institute of Technology and the
National Science Foundation's National Radio Astronomy Observatory. Unlike
normal black holes, which weigh several times the mass of the Sun,
supermassive black holes reside in the hearts of galaxies and can be
as massive as several hundred million times that of the Sun.
Nearest Extrasolar Planet
On Aug 7, 2000 a team of astronomers led by Dr.
William Cochran of the University of Texas McDonald Observatory [USA],
announced the discovery of the nearest planet outside the solar System. The
Planet - probably slightly larger than Jupiter - orbits the star Epsilon
Eridani. This star, at only 10.5 light years distant, is one of the
closet stars to the Sun, which means that is is the main phase of its life
span
Brightest Planet
Viewed from Earth, the brightest of the five
planets normally visible to the naked eye (Jupiter, Mars, Mercury, Saturn,
and Venus) is Venus, which has a maximum magnitude of -4.4. In clear
conditions, and if you know where to look, Venus can often be viewed during
the day. The planet is often at the root of supposed UFO sightings. A thick
white blanket of clouds perpetually shroud this rocky planet, hiding the
surface from view.
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Nearest Star Cluster
The Hyades cluster in the constellation of Taurus
[the Bull] is the nearest star cluster to our Solar System. It contains
around 300 stars, which are roughly 150 light years away and have been
estimated to be 625 million years old.
Brightest Supernova Of Modern Times
In February 1987, a giant star within the Large
Magellanic Cloud exploded in the brightest supernova of modern times. Its
maximum brightness was magnitude 2.3, easily visible to the naked eye. As
the star runs out of hydrogen fuel, it begins to use heavier and heavier
elements as its nuclear fuel. Eventually, iron is formed in the core, which
prevents further fusion reactions from occuring within the star. As fusion
shuts down, the star collapses in upon itself and then blows itself to
pieces as a supernova.
Largest Galaxy
The central galaxy of the Abell 2029 galaxy
cluster, 1070 million light years distant in Virgo, has a major diameter of
5,600,000 light years - 80 times the diameter of our own Milky Way galaxy.
Farthest Object Visible By The Naked Eye
The remotest heavenly body visible with the naked eye is the Great Galaxy in
the constellation of Andromeda. A silver smudge in the sky gives the
Andromeda Galaxy away - at a mind-boggling 2,200,000 light years from Earth,
anyone can spot it! One of the closest galaxies to our own, the light we see
is the result of 200,000,000,000 stars shining together. The spiral galaxy
is said to have been discovered by German astronomer, Simon Marius, around
1611.
Brightest Nebula
The Orion Nebula (M42 (Messier 42)) is the
brightest nebula in the sky, with an apparent magnitude of 4. Located in the
'sword' of the constellation of Orion, the nebula is easily visible to the
naked eye.
A nebula is a vast cloud of gas and dust. Some are dark but others glow by
reflecting starlight or by emitting their own light due to stars embedded
within them. Although the Orion Nebula is around 1,500 light years from
Earth, it can be seen in the night sky without a telescope. Although it
looks bright and substantial, the Orion Nebula is extremely diffuse and
rarified. If you took a 3 cm-wide core sample right through its 16 light
year width, you would only gather enough mass to balance a small coin. The
Orion Nebula is the best example of what is called a diffuse nebula. Diffuse
nebulae either emit their own light or reflect the light of nearby stars,
while dark nebulae obscure the stars behind them. The extremely bright light
from the Orion Nebula comes from hundreds of very hot (O-type) young stars
clustered around four larger stars known as the Trapezium. Thanks to the
work of the Hubble Space Telescope, images of the nebula have continued to
improve and scientists can now photograph light-emitting objects that had
never been seen before and even watch stars being "born".
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