The Lobster Nebula seen with ESO’s VISTA telescope
Wide-field view of the area of NGC 6357
Comparison of VISTA image of NGC 6357 with a visible light image
Videos
New infrared VISTA image of NGC 6357
A new image from ESO’s VISTA telescope
captures a celestial landscape of glowing clouds of gas and tendrils of
dust surrounding hot young stars. This infrared view reveals the stellar
nursery known as NGC 6357 in a surprising new light. It was taken as
part of a VISTA survey that is currently scanning the Milky Way in a bid
to map our galaxy’s structure and explain how it formed.
Located around 8000 light-years away in the constellation of Scorpius
(The Scorpion), NGC 6357 — sometimes nicknamed the Lobster Nebula [1]
due to its appearance in visible-light images — is a region filled with
vast clouds of gas and tendrils of dark dust. These clouds are forming
stars, including massive hot stars which glow a brilliant blue-white in
visible light.
This image uses infrared data from ESO’s Visible and Infrared Survey
Telescope for Astronomy (VISTA) at the Paranal Observatory in Chile. It
is just a small part of a huge survey called VISTA Variables in the Vía Láctea (VVV) that is imaging the central parts of the Galaxy (eso1242). The new picture presents a drastically different view to that seen in visible-light images — such as the image taken
with the 1.5-metre Danish telescope at La Silla — as infrared radiation
can penetrate much of the covering of dust that shrouds the object [2].
One of the bright young stars in NGC 6357, known as Pismis 24-1, was
thought to be the most massive star known — until it was found to
actually be made up of at least three huge bright stars, each with a
mass of under 100 times that of our Sun. Even so, these stars are still
heavyweights — some of the most massive in our Milky Way. Pismis 24-1 is
the brightest object in the Pismis 24 star cluster, a bunch of stars
that are all thought to have formed at the same time within NGC 6357.
VISTA is the largest and most powerful survey telescope ever built,
and is dedicated to surveying the sky in infrared light. The VVV survey
is scanning the central bulge and some of the plane of our galaxy to
create a huge dataset that will help astronomers to discover more about
the origin, early life, and structure of the Milky Way.
Parts of NGC 6357 have also been observed by the NASA/ESA Hubble Space Telescope (heic0619a) and ESO’s Very Large Telescope (eso1226a).
Both telescopes have produced visible-light images of various parts of
this region — comparing these images with this new infrared image above
shows some striking differences. In the infrared the large plumes of
red-hued material are much reduced, with tendrils of pale, purple gas
stretching out from the nebula in different areas.
Notes
[1] The informal name of Lobster Nebula is also sometimes given to the spectacular star-forming region Messier 17 (eso0925), although that object is more often called the Omega Nebula.
[2] Infrared observations can reveal features that
cannot be seen in visible-light pictures, for example because an object
is too cold, obscured by thick dust, or is very distant, meaning that
its light has been stretched towards the red end of the spectrum by the
expansion of the Universe.
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
