First Photos from Infrared Space Telescope

http://www.space.com/scienceastronomy/spitzer_first_031218.html

[Follow the link to see some beautiful pics. As fine as the best of
Hubble]


NASA announced the formal name of its newest space telescope today and
released the first science pictures. The images support a promise that
the orbiting observatory, now called the Spitzer Space Telescope, will
provide top-notch science and entertainment on par the Hubble Space
Telescope.

"Every time we take a picture, we see something spectacular," said
Giovanni Fazio of the Smithsonian Astrophysical Observatory (SAO).



Initially called the Space Infrared Telescope Facility (SIRTF), the
observatory is now named after the late Lyman Spitzer, Jr., who in the
1940s first proposed putting telescopes in space to overcome the
limiting effects of Earth's atmosphere.

The name was chosen from 7,000 public suggestions.

Spitzer, as the telescope is sure to be informally known, launched
Aug. 25 and spent its first weeks in space undergoing instrument
checkout. It is working "extremely well," project scientist Michael
Werner, of NASA's Jet Propulsion Laboratory, said at a press
conference.

The new photographs illustrate Spitzer's range of targets and
capabilities. They provide fresh details of a nearby galaxy, a peek at
star formation inside a corner of our own galaxy, an updated view of a
planet-forming disk around a nearby star, and new details of a comet
and a pair of asteroids. The telescope also discovered water for first
time in a galaxy so far away that it is observed at a time when life
was just developing on Earth, Spitzer scientists said.

The initial observations are modest compared to what is expected.

"Like Hubble, Compton and Chandra, the new Spitzer Space Telescope
will soon be making major discoveries, and, as these first images
show, should excite the public with views of the cosmos like we've
never had before," said Ed Weiler, NASA's associate administrator for
space science.

The pictures

The telescope gathers infrared light, an invisible form of
electromagnetic radiation associated with heat. It allows astronomers
to see through layers of dust, which block visible light, and detect
heat emitted by deeply embedded dust around myriad cosmic objects.



For astronomer-detectives, it's like looking through walls.

One Spitzer image showcases a relatively nearby galaxy called M81. The
picture resolves features not seen before, astronomers said, and will
allow them to estimate a rate of star formation in a galaxy much like
our own.

"By studying M81, we can get an outsider's view of our home," said the
SAO's Fazio. "This is what aliens would see if they looked back at the
Milky Way."

Fazio is the principle investigator for the telescope's Infrared Array
Camera (IRAC).

At the center of M81 is a blue-white bulge of old stars. The galaxy's
spiral arms are loaded with dust bathed in stellar radiation. Bright
knots of material in the arms are sites where massive stars are
developing in giant clouds of hydrogen.

M81 is near the Big Dipper in the night sky and can be found with
binoculars. It is 12 million light-years away. White objects in the
image are foreground stars in our own galaxy.

Stellar nurseries



Another striking new picture looks through a dark cloud astronomers
call the Elephant's Trunk Nebula to glimpse a stellar nursery. Inside
a region called a globule, young stars and stars-to-be are seen for
the first time.

The nebula sits within a larger nebula called IC 1396, in the
constellation of Cepheus. It is about 2,450 light-years away. Star
formation in the globule is forced along because the cloud is
pressurized by intense radiation and a "wind" of charged particles
from a massive star, which is to the left of the cloud and outside the
picture. The pressure also creates the colorful filamentary structure
of the globule.

A half-dozen reddish, newborn stars have been found behind the
globule's dusty veil.

"Radiation and hot winds are carving away the nebula like rust
sandblasted from an old car," Fazio said. "Eventually, it will vanish
completely. We're lucky to have caught it in the act, to get a chance
to see these stunning ethereal wisps before they disappear."

In another image, Spitzer captured the energetic outflow of an
embryonic, Sun-like star that is hidden from view to visible-light
telescopes.



The picture shows a Herbig-Haro object, a bright region of gas and
dust formed by high-speed outflows of gas from a developing star. This
one is called HH 46/47. The polar outflows -- stuff shooting out in
two opposite directions, are linked to material around the star that
is forming a disk, where planets might be born.

The action all sits inside a dark cloud called a Bok globule, which is
illuminated by the nearby Gum Nebula. It is about 1,140 light-years
away in the constellation Vela. Astronomers said the scene is
reminiscent of the birth of our own Sun.

"Together, these three images show how IRAC will serve as a 'time
machine,' giving us new information about the past, present, and
future of our cosmos," Fazio said.

Planetary nursery

Using its Multiband Imaging Photometer (MIPS), the observatory
examined a disk of gas and dust around the nearby star Fomalhaut, the
18th brightest star in our night sky.

Fomalhaut is young and thought to be forming planets in its environs.
It is surrounded by a disk of dust five times larger than our solar
system. Separate observations last year, in a different wavelength of
light, suggested Fomalhaut harbors a newborn, Saturn-like planet.

The new infrared observations confirm suspicions that something is
developing.

One lobe of dust in the ring is one-third brighter than another. The
uneven distribution of dust could be produced by a collision between
asteroids, creating clouds of dust, or by the steering effects on dust
under the gravitational influence of an unseen planet, Spitzer
astronomers said.

Closer to the star there is less dust, a situation akin to the hole of
a donut. But there is some dust there, in a region within 10 times the
distance of Earth to the Sun. This inner, sparser batch of dust is
warmer, the new observations show. Astronomers said it might mean
planets farther out are nudging comets into the "hole," as occurs in
our own solar system. Upon approaching the star, these comets would
then release the dust seen by Spitzer.

Strange comet, and a surprise

Finally, Spitzer took a look at our cosmic backyard, using MIPS to
image a comet in our solar system known for strange behavior.



Comet Schwassmann-Wachmann 1 has a 15-year, nearly circular orbit
around the Sun, out beyond Jupiter. Comets are visible only because
their surfaces and surrounding material reflect sunlight. This comet
experiences frequent outbursts, when it can brighten 1,000 times
normal.

The outbursts are thought to be caused by a build-up of internal
pressure as solar heat gradually evaporates frozen carbon dioxide and
carbon monoxide from beneath the comet's black crust, theorists say.
When pressure exceeds the strength of the crust, it ruptures and a
burst of gas and dust is shot into space at 450 mph (200 meters per
second).

The nucleus of the comet -- too small for Spitzer to resolve -- is
about 18 miles wide (30 kilometers).

As often happens in astronomy, unexpected findings resulted from this
picture.

In photographing the icy object, Spitzer serendipitously imaged two
previously known asteroids. Because they are closer to Earth than the
comet, they orbit the Sun more quickly and appear to move in relation
to the comet and background stars. The asteroids therefore appear
slightly elongated in the long-exposure photograph.

Using the image data, astronomers were able to estimate how reflective
the surfaces of the asteroids are, providing a better estimate of each
rock's size. They are about 1.7 miles (2.8 kilometers) and 3.7 miles
(6 kilometers) wide -- the smallest asteroids in or beyond the main
asteroid belt ever measured by an infrared telescope.

Not just pretty pictures

Spitzer is the last of NASA's four Great Observatories, which include
the Chandra X-ray Observatory, the now-deorbited Compton Gamma Ray
Observatory, and Hubble, which sees the universe in visible light,
ultraviolet and infrared. Spitzer is devoted to infrared observations
at specific wavelengths Hubble can't detect.



Astronomers also used Spitzer to gather important data, but not
pictures, on the chemical makeup of a galaxy 3.2 billion light-years
away. The observations of galaxy IRAS F00183-7111 reveal several of
the building blocks of life.

A spectrograph aboard Spitzer breaks infrared light into its
constituent colors, just as a prism splits white light into its
components.

Studying chemical fingerprints in the spectra, scientists found the
distant galaxy contains silicates similar to beach sand and organic
molecules made of carbon and hydrogen, two of the most common elements
on Earth.

They also found the most crucial element for life, water.

Picking the name

The telescope's new name was submitted to a NASA-run contest by
28-year-old Jay Stidolph of Fort Nelson, British Columbia.



Lyman Spitzer, Jr. (1914-1997) was a physicist at Yale, Columbia and
Princeton universities. He studied stellar dynamics and the
interstellar medium. In 1946, he suggested that space-based telescopes
could avoid the blurring effects of Earth's atmosphere and be able to
see space in wavelengths of light that don't penetrate the atmosphere.

NASA officials credit his continuing efforts as leading to the
development of the Hubble telescope.

Interestingly, Stidolph was the only person to suggest Spitzer as the
name. The most frequently suggested names were "Red Eye" and "Sagan."

Stidolph actually recommended the telescope be called the "Spitzer
Deep Space Observatory." A committee of science writers,
communicators, educators and NASA program managers sent NASA a list of
semifinalists. Upper management of the space agency made the final
decision.

The new observatory is managed by JPL. Science operations are
conducted at the Spitzer Science Center at the California Institute of
Technology.



xponent

Expansive Final Frontier Maru

rob


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