Source : Discover
Name : HB 209458b,nickname OSIRIS.
Location : 153 Light--Years from Earth in the comstellation
Pegasus--a relatively close neighbor within our
qalaxy.
Age : 4.5 billion years old,abt the same as
Earth.
GENERAL CHARACTERISTICS :
Even within the exotic category of
planets that circle other stars,the one revolving ard the star HD
209458 is special.Five yrs ago,David Chearbonneau of the
harvard-smith--sonian center for Astrophspheric and Tim Brown of
the national center for atmospheric Research in Boulder observed
this planet pass in front of iys star once every three
days,12hrs,and 35 mins,each time casting an extremely slight
shadow.That shaow allows reing an extremely slight shadow.That
shadow allows researchers to stretch their senses across 900
trillion miles of space and learn exactly wat a distant planet is
like.
Charbonneau,Brown,and their collegues quickly began to nail dw the
details.They timed the eclipses and determined that the planet
follows a perfectly circular path ard HB 209458,obiting at a
distance of 4.3 million miles.Another team had previously
discovered the planet and measured
its mass---adt 220 times Earth's and roughly two-birds as much as
jupiter's---based on the way it tugs on its parent star.The
intensity of the eclipses shows the planet is abt 35 percent larger
in circumference than jupiter.Together,the numbers paint a picture
of a tortured world circling so close to its star that a year
speeds by in just three and a half Earth days.The furious rays
pounding dw on its alien palnet heat it to 2,000 degrees Fahrenheit
and cause it to puff up like a marshmallow over a campfire.
Later oberservations led by alfred vidal-madjar at the astrophysics
institude of Paris also exposed the smells of the planet,which he
nicknamed OSIRIS.By watching starlight streaming through the
planet's atmosphere,vidar-madjar discovered a cloud of hydrogen
gas,as well as possible hints of oxygen and carbon,boiling off into
space.The composition is abt wat you'd get if you put jupiter under
an enormous heat lamp,suggesting that Osiris is made of the same
stuff as the eclipses might reveal atmospheric layers,clouds,and
even winds.
RANCE & POPULATION Roughly 10 percent of nearby sunlike stars
have massive planets,so there may be 10 billion of them in our
galaxy.Researchers know of nine eclipsing planets,including one
that is bloated and another that is oddly dense.
HOW TP SPOT IT The star HD 209458 is visible thru binoculars.Lights
from its planet has been directly observed only the spitzer space
telescope,the image above is an artist's
interpretion.
