The planetary nebula IC 1295 in the constellation of Scutum (The Shield)
Videos
ESO's VLT snaps a planetary nebula
This intriguing new picture from ESO’s
Very Large Telescope shows the glowing green planetary nebula IC 1295
surrounding a dim and dying star located about 3300 light-years away in
the constellation of Scutum (The Shield). This is the most detailed
picture of this object ever taken.
Stars the size of the Sun end their lives as tiny and faint white
dwarf stars. But as they make the final transition into retirement their
atmospheres are blown away into space. For a few tens of thousands of
years they are surrounded by the spectacular and colourful glowing
clouds of ionised gas known as planetary nebulae.
This new image from the VLT shows the planetary nebula IC 1295, which
lies in the constellation of Scutum (The Shield). It has the unusual
feature of being surrounded by multiple shells that make it resemble a
micro-organism seen under a microscope, with many layers corresponding
to the membranes of a cell.
These bubbles are made out of gas that used to be the star’s
atmosphere. This gas has been expelled by unstable fusion reactions in
the star’s core that generated sudden releases of energy, like huge
thermonuclear belches. The gas is bathed in strong ultraviolet radiation
from the aging star, which makes the gas glow. Different chemical
elements glow with different colours and the ghostly green shade that is
prominent in IC 1295 comes from ionised oxygen.
At the centre of the image, you can see the burnt-out remnant of the
star’s core as a bright blue-white spot at the heart of the nebula. The
central star will become a very faint white dwarf and slowly cool down
over many billions of years.
Stars with masses like the Sun and up to eight times that of the Sun,
will form planetary nebulae as they enter the final phase of their
existence. The Sun is 4.6 billion years old and it will likely live
another four billion years.
Despite the name, planetary nebulae have nothing to do with planets.
This descriptive term was applied to some early discoveries because of
the visual similarity of these unusual objects to the outer planets
Uranus and Neptune, when viewed through early telescopes, and it has
been catchy enough to survive [1]. These objects were shown to be glowing gas by early spectroscopic observations in the nineteenth century.
This image was captured by ESO’s Very Large Telescope, located on
Cerro Paranal in the Atacama Desert of northern Chile, using the FORS
instrument (FOcal Reducer Spectrograph). Exposures taken through three
different filters that passed blue light (coloured blue), visible light
(coloured green), and red light (coloured red) have been combined to
make this picture.
Notes
[1] Even early observers such as
William Herschel, who discovered many planetary nebulae and speculated
about their origin and composition, knew that they weren’t actually
planets orbiting the Sun as they did not move relative to the
surrounding stars.
More information
ESO is the foremost intergovernmental
astronomy organisation in Europe and the world’s most productive
ground-based astronomical observatory by far. It is supported by 15
countries: Austria, Belgium, Brazil, the Czech Republic, Denmark,
France, Finland, Germany, Italy, the Netherlands, Portugal, Spain,
Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious
programme focused on the design, construction and operation of powerful
ground-based observing facilities enabling astronomers to make
important scientific discoveries. ESO also plays a leading role in
promoting and organising cooperation in astronomical research. ESO
operates three unique world-class observing sites in Chile: La Silla,
Paranal and Chajnantor. At Paranal, ESO operates the Very Large
Telescope, the world’s most advanced visible-light astronomical
observatory and two survey telescopes. VISTA works in the infrared and
is the world’s largest survey telescope and the VLT Survey Telescope is
the largest telescope designed to exclusively survey the skies in
visible light. ESO is the European partner of a revolutionary
astronomical telescope ALMA, the largest astronomical project in
existence. ESO is currently planning the 39-metre European Extremely
Large optical/near-infrared Telescope, the E-ELT, which will become “the
world’s biggest eye on the sky”.
Links
Contacts
Richard HookESO, La Silla, Paranal, E-ELT & Survey Telescopes Press Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org
