Planet gets a new image

On April 29, an international team of astronomers, one of whom
is a professor at UCLA, confirmed the first image of a planet
outside of our solar system.

The giant planet, which is about five times the mass of Jupiter,
is gravitationally bound to a brown dwarf, which is a failed star.
Both objects, one of which is orbiting the other, are moving across
the sky, away from Earth.

The planet, coupled with the brown dwarf, form the 2M1207
system, which is about 200 to 250 light years away.

The planet’s distance from the brown dwarf is about twice
as far as Neptune is from the sun. Astronomers speculate the two
objects are about 8 million years old, considered young relative to
our solar system, which is believed to be about 4.6 billion years
old.

This is the first time that astronomers have been able to
identify a planet outside of our solar system, and it marks the
beginning of a journey to discover other solar systems and planets.
Scientists are especially interested in planets that can support
life, which could perhaps be a future home for us.

Another system, AB Pictoris, about 150 light years away from
Earth, was also recently identified in images obtained by the same
European/American team. The estimated 30-million-year-old system
consists of a star called AB Pictoris and an object rotating around
it at a radius about 9 times the distance from Neptune to the sun.
The nature of this object is uncertain, but its immense size, 13 to
14 times the mass of Jupiter, makes it a possible planet or a brown
dwarf.

Brown dwarfs are the link between giant gas planets like
Jupiter, and small, low-mass stars. Stars are different from brown
dwarfs because of the different elements involved in the fusion
process, their internal source of energy. Brown dwarfs emit almost
no visible light.

Images of 2M1207 and AB Pictoris were taken with the European
Southern Observatory’s telescope in northern Chile. The
Hubble Space Telescope also obtained images in August 2004.

Analyzing images and spectra can help determine properties such
as heat, its chemical composition, and its motion in the
atmosphere.

Designs and studies are currently underway by NASA and the
European Space Agency to create telescopes capable of obtaining
more informative data.

“In a decade or two, we are hoping to have satellites that
obtain images with new instrumentation that would help us find
planets that are more like Earth,” said Ben Zuckerman,
professor of physics and astronomy at UCLA, member of NASA’s
Astrobiology Institute, and member of the team studying 2M1207.

Though these recent discoveries are not Earth-like planets, they
may ultimately lead to finding planets that are similar to Earth
and can support life.

Astronomers searching for terrestrial planets have many sources
of motivation, including the foresight of a potential crisis.

“It is a supreme irony that while humans search for life
on other planets, we are making Earth less hospitable for
life,” said Zuckerman.

According to his article in Mercury Magazine, the human species
is currently expropriating about 50 percent of various critical
natural resources for our own use, leaving less and less for other
species, and jeopardizing the future of all life on Earth.

In addition to the destruction of natural resources and the
permanent environmental damage humans have caused, space on Earth
that is not being used for agriculture, grazing, timber, recreation
and waste disposal is virtually nonexistent.

“Population growth has a huge inertia associated with
it,” said Zuckerman, whose concerns, combined with the
curiosity of life outside of our planet, fuel his motivation to
search for terrestrial planets, like many other scientists.

“Our discovery represents a first step toward one of the
most important goals of modern astrophysics: to characterize the
physical structure and chemical composition of giant and,
eventually, terrestrial-like planets,” said Anne-Marie
Lagrange in a UCLA press release. She is another member of the team
from the Grenoble Observatory in France who studied the new images
of 2M1207 and AB Pictoris.