It's not
exactly Doc Brown's DeLorean from "Back to the Future," but the
European Space Agency's (ESA) Planck Observatory will be something of a cosmic
time machine after it launches this week.
Planck will
be launched
by ESA along with the Herschel Space Observatory aboard an Ariane 5 ECA
launcher from the Guiana Space Centre in Kourou, French Guiana on May 14.
While
Herschel sets its sights on the cold infrared radiation of space, Planck
will be looking at the remnants of the first light to shine freely in the
universe, effectively allowing astronomers to look back in time.
This relic
radiation is called the Cosmic Microwave Background, and was discovered by
accident in 1965. The CMB is an "echo" of the Big Bang, the cooled remnant of
the first light emitted after the universe had cooled enough to allow it to
travel freely.
"The cosmic
microwave background shows us the universe directly at age 400,000 years, not
the movie, not the historical novel, but the original photons," said Charles
Lawrence, NASA project scientist for Planck at JPL.
Kinky universe
The CMB can
be detected in all directions of the sky at an average temperature of 2.73 degrees
Kelvin (-450 degrees Fahrenheit or -270 degrees Celsius). Previous space-based
missions have found that the temperature of the CMB varies ever so slightly in
different areas.
Planck is
built to resolve these variations in greater detail, which could allow
scientists to better understand the conditions of the very early universe. In
fact, Planck will be bringing temperatures variations into the sharpest focus
possible.
The kinks in
the early universe are thought to have given rise to the structures we see
in space today: galaxies, galaxy clusters and large voids.
The photons
in the CMB could also tell astronomers when and how the first stars formed.
Essentially,
Planck will help reveal the initial conditions from which the universe we know
today evolved.
"Planck
will give us the clearest view ever of this baby universe, showing us the
results of physical processes in the first brief moments after the Big Bang,
and the starting point for the formation of stars and galaxies," Lawrence said.
Question
of density
Planck is
also planned to determine the density of normal matter in the universe, which
will allow astronomers to calculate the total number of atoms present in the
universe. Planck will also probe the mysterious dark matter and dark energy
though to pervade the universe — dark matter is though to make up 90 percent of
the matter in the universe and dark energy is thought to be the behind the
acceleration of the expansion of the universe.
Better
understanding the nature
of dark energy could help answer a key question about the future of the
universe: "Will it keep on expanding for ever or some day collapse back
upon itself?" said Simon White of the Max Planck Institute for
Astrophysics in Germany, which developed key software for Planck.
Closer to
home, Planck will map the cold dust along the Milky Way's spiral arms for the
first time. The telescope will also produce a 3-D map of our galaxy's magnetic
field.
Planck will
also do a little observing to overlap with Herschel, looking at distant radio
galaxies to shed light on star and galaxy formation.
Planck is
slated for a 15-month mission, time enough for two full surveys of the sky. The
mission could be extended for another year, but even with the 15 months, "Planck
will give an answer to many important questions of cosmology," White said.
"The satellite is the most powerful tool ever for studying the Cosmic
Microwave Background developed."
advertisement
