NASA announced the formal name of its newest space telescope on Thursday 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 a par with the Hubble Space Telescope.
"Every time we take a picture, we see something spectacular," said Giovanni Fazio of the Smithsonian Astrophysical Observatory.
Initially called the Space Infrared Telescope Facility, 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 with 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," Fazio said. "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, or 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, sunlike 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 . 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, or 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 , in a different wavelength of light, suggested Fomalhaut harbors a newborn, Saturnlike 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.
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 buildup 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 (30 kilometers) wide.
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.
Spitzer is the last of NASA's four Great Observatories, which include the , the now-deorbited , and , which sees the universe in visible light, ultraviolet and infrared. Spitzer is devoted to infrared observations at specific wavelengths Hubble can't detect.
nterestingly, 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 the Jet Propulsion Laboratory. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology.