Since then, the lander has experience three
Martian seasons, autumn winter and spring. The sunlight in its
location is presently about the same as it was when the lander
stopped transmitting and there is a
slim chance that the unit could become operational again. NASA
does not expect this to be the case however, as the lander was not
designed to weather the brutal Martian winter temperatures.
will be monitoring for radio communication attempts from the Phoenix
with the Mars
Odyssey craft which is presently in orbit over Mars. Should no
signals be received, they will try again in February and
Ultimately, even if the craft does not rise like a
phoenix from its icy grave, it has transmitted a wealth of
information about the Martian surface and atmosphere during its
Astronomers from Caltech have spotted
the second smallest confirmed exoplanet using the Hawaiian Keck I
telescope. The 10 meter lens coupled with the High Resolution Echelle
Spectrometer (HIRES) viewed the planet by way of radial velocity
measurement. An orbiting planet causes a star to wobble, and as it
wobbles, its detectable light is shifted towards red or blue. The
HIRES instrument captures this shift and astronomers can calculate
the planet’s mass and orbital characteristics using the data.
156668b has approximately
four times the mass of Earth (just shy of the five Earth masses
of recently discovered rocky
exoplanet CoRoT-7b) but orbits HD 156668 in just four days. The only smaller
confirmed exoplanet is Gliese 581 e, which, found in April of 2009,
weighs in at just under two Earth masses.
HR 8799c, has received the honor of being the first planet for which
observation of atmospheric chemical composition has been made.
The observations were made using the European Southern Observatory’s
Very Large Telescope. The planet is roughly ten times of the mass of
Jupiter and orbits between two to two and half times the distance
from HR 8799 as Uranus does our Sun.
Two major factors
combined make these observations laudable. First, HR 8799 is a very
bright star, shining nearly five times as bright as the Sun, though
having only approximately and one and a half times its mass. Second,
the planetary system is on a plane nearly perpendicular to Earth’s
point of view, rather than parallel as most observed extra-solar
systems have been. Scientists observing parallel plane systems can
use a deductive method for capturing spectra, comparing a star’s
measured data before, after and during a planetary eclipse, to find
out which light was coming from the star and which from the planet.
In a perpendicular orbital system, this is not possible as the planet
and star are both in view at all times.
“It's like trying to
see what a candle is made of, by observing it from a distance of two
kilometres when it’s next to a blindingly bright 300 Watt lamp,”
explains Markus Janson, lead author of the paper describing the
measurements and methods used to capture HR 8799c’s direct
Understanding what a planet’s atmosphere is
composed of can help planetary scientists understand how it was
formed. This in turn will help them understand how solar systems may
be formed as a whole.
HR 8779 can be found in the Gemini
constellation. Aside from three giant planets, it also has two debris
belts similar to our own solar system’s asteroid and Kuiper belts.