Buy the Gomez's Hamburger space photo.
High quality Hubble picture, slide, or Duratrans backlit transparency. NASA photograph H2002-19
. Wide variety of sizes.
Click to see selection as Astronomy Picture of the Day (APOD) - August 7, 2002
Hold the pickles; hold the lettuce. Space is serving up giant
hamburgers. NASA's Hubble Space Telescope has snapped a photograph of a
strange object that bears an uncanny resemblance to a hamburger. The
object, nicknamed Gomez's Hamburger, is a sun-like star nearing the end
of its life. It already has expelled large amounts of gas and dust and
is on its way to becoming a colorful, glowing planetary nebula.
The ingredients for the giant celestial hamburger are dust and light.
The hamburger buns are light reflecting off dust and the patty is the
dark band of dust in the middle. The Hubble Heritage image, taken Feb.
22, 2002, with the Wide Field Planetary Camera 2, shows the structure of
Gomez's Hamburger with high resolution, particularly the striking dark
band of dust that cuts across the middle. The dark band is actually the
shadow of a thick disk around the central star, which is seen edge-on
from Earth. The star itself, with a surface temperature of approximately
18,000 degrees Fahrenheit (10,000 degrees Celsius), is hidden within
this disk. However, light from the star does emerge in the directions
perpendicular to the disk and illuminates dust above and below it.
The reason why the star is surrounded by a thick, dusty disk remains
somewhat uncertain. It is possible that the central object is actually
a pair of stars. If so, then the star that ejected the nebula may be
rapidly rotating, expelling material mostly from its equatorial regions.
Stars with masses similar to our Sun's end their lives as planetary
nebulae. The star evolves to become a bloated red giant, with a girth
about 100 times greater than its original diameter. Then it ejects its
outer layers into space, exposing the star's hot core. Ultraviolet
radiation from the central core streams out into the surrounding
ejected gas, causing it to glow. The glowing gas is called a planetary
nebula. The Hubble Space Telescope has provided numerous spectacular
images of planetary nebulae over the past several years, including the
Ring Nebula and several others that have been released in the Hubble
Less well known are "proto-planetary nebulae," objects like Gomez's
Hamburger that are in a state of evolution immediately before the true
planetary-nebula stage. Just after the red giant expels its outer
layers, the remnant star in the center is still relatively cool.
Consequently, it emits ordinary visible light, but very little
ultraviolet radiation. Therefore the surrounding gas does not glow.
However, the ejected material also contains vast numbers of microscopic
dust particles, which can reflect the starlight and make the material
visible. This same effect of light scattering produces halos around
streetlights on a foggy night.
The lifetime of a proto-planetary nebula is very brief. In less than a
thousand years, astronomers expect that the central star will become hot
enough to make the dust particles evaporate, thus exposing the star to
view. At that time the surrounding gas will glow. Gomez's Hamburger will
have become a beautiful, glowing planetary nebula.
Gomez's Hamburger was discovered on sky photographs obtained by Arturo
Gomez, an astronomer at the Cerro Tololo Inter-American Observatory in
Chile. The photos suggested that there was a dark band across the
object, but its exact structure was difficult to determine because of
the atmospheric turbulence that hampers all images taken from the
ground. Gomez's Hamburger is located roughly 6,500 light-years away in the
August 1, 2002
Image Credit: NASA and the Hubble Heritage Team (STScI/AURA)