ESA ESO: The Helix in New Colours

ESO’s VISTA telescope, at the Paranal Observatory in Chile, has captured a striking new image of the Helix Nebula. 

This picture, taken in infrared light, reveals strands of cold nebular gas that are invisible in images taken in visible light, as well as bringing to light a rich background of stars and galaxies.

The Helix Nebula is one of the closest and most remarkable examples of a planetary nebula.

It lies in the constellation of Aquarius (The Water Bearer), about 700 light-years away from Earth.

This strange object formed when a star like the Sun was in the final stages of its life.

Unable to hold onto its outer layers, the star slowly shed shells of gas that became the nebula. It is evolving to become a white dwarf star and appears as the tiny blue dot seen at the centre of the image.

The nebula itself is a complex object composed of dust, ionised material as well as molecular gas, arrayed in a beautiful and intricate flower-like pattern and glowing in the fierce glare of ultraviolet light from the central hot star.

The main ring of the Helix is about two light-years across, roughly half the distance between the Sun and the nearest star. However, material from the nebula spreads out from the star to at least four light-years.

This is particularly clear in this infrared view since red molecular gas can be seen across much of the image.

While hard to see visually, the glow from the thinly spread gas is easily captured by VISTA’s special detectors, which are very sensitive to infrared light.

The 4.1-metre telescope is also able to detect an impressive array of background stars and galaxies.

The powerful vision of ESO’s VISTA telescope also reveals fine structure in the nebula’s rings. The infrared light picks out how the cooler, molecular gas is organised.

The material clumps into filaments that radiate out from the centre and the whole view resembles a celestial firework display.

Even though they look tiny, these strands of molecular hydrogen, known as cometary knots, are about the size of our Solar System.

The molecules in them are able to survive the high-energy radiation that emanates from the dying star precisely because they clump into these knots, which in turn are shielded by dust and molecular gas. It is currently unclear how the cometary knots may have originated.

The Milky Way by ESO Photo Ambassador Yuri Beletsky

An incredible image of the Milky Way by ESO Photo Ambassador Yuri Beletsky.

See 12 more Photos from this series here.

ESA ESO VISTA: New globular star clusters found in Milky Way

This image from VISTA is a tiny part of the VISTA Variables in the Via Lactea (VVV) survey that is systematically studying the central parts of the Milky Way in infrared light. 

On the right lies the globular star cluster UKS 1 and on the left lies a much less conspicuous new discovery, VVV CL001 - a previously unknown globular, one of just 160 known globular clusters in the Milky Way at the time of writing. 

The new globular appears as a faint grouping of stars about 25 percent of the width of the image from the left edge, and about 60 percent of the way from bottom to top. Credit: ESO/D. Minniti/VVV Team.

The dazzling globular cluster called UKS 1 dominates the right-hand side of the first of the new infrared images from ESO's VISTA survey telescope at the Paranal Observatory in Chile.

But if you can drag your gaze away, there is a surprise lurking in this very rich star field - a fainter globular cluster that was discovered in the data from one of VISTA's surveys.

You will have to look closely to see the other star cluster, which is called VVV CL001: it is a small collection of stars in the left half of the image.

But VVV CL001 is just the first of VISTA's globular discoveries. The same team has found a second object, dubbed VVV CL002.

This small and faint grouping may also be the globular cluster that is the closest known to the centre of the Milky Way.

The discovery of a new globular cluster in our Milky Way is very rare. The last one was discovered in 2010, and only 158 globular clusters were known in our galaxy before the new discoveries.

These new clusters are early discoveries from the VISTA Variables in the Via Lactea (VVV) survey that is systematically studying the central parts of the Milky Way in infrared light.

The VVV team is led by Dante Minniti (Pontificia Universidad Catolica de Chile) and Philip Lucas (Centre for Astrophysics Research, University of Hertfordshire, UK).

ESA ESO VLT Astronomers crack the Fried Egg Nebula

If the Fried Egg Nebula were placed in the centre of the Solar System, the Earth would lie deep within the star itself and the planet Jupiter would be orbiting just above its surface. Image by European Southern Observatory's Very Large Telescope.

Using the European Southern Observatory's Very Large Telescope (VLT), teams from The University of Manchester, among others, took the new picture showing for the first time a huge dusty double shell surrounding the central hypergiant.

The star and its shells resemble an egg white around a yolky centre, leading the astronomers to nickname the object the Fried Egg Nebula. The international team's results are published in the journal Astronomy and Astrophysics.

The monster star, known to astronomers as IRAS 17163-3907, has a diameter about a thousand times bigger than our Sun. At a distance of about 13 000 light-years from Earth, it is the closest yellow hypergiant found to date and new observations show it shines some 500 000 times more brightly than the Sun.

The observations of the star and the discovery of its surrounding shells were made using the VISIR infrared camera on the VLT. The pictures are the first of this object to clearly show the material around it and reveal two almost perfectly spherical shells.

If the Fried Egg Nebula were placed in the centre of the Solar System, the Earth would lie deep within the star itself and the planet Jupiter would be orbiting just above its surface.

The much larger surrounding nebula would engulf all the planets and dwarf planets and even some of the comets that orbit far beyond the orbit of Neptune. The outer shell has a radius of 10 000 times the distance from the Earth to the Sun.

"This object was known to glow brightly in the infrared but, surprisingly, nobody had identified it as a yellow hypergiant before," said Eric Lagadec (European Southern Observatory), who led the team that produced the new discovery.

Yellow hypergiants are in an extremely volatile phase of their evolution, undergoing a series of explosive events - this star has ejected four times the mass of the Sun in just a few hundred years. The material flung out during these bursts has formed the extensive double shell of the nebula, which is made of dust rich in silicates and surrounded by gas.

Professor Albert Zijlstra, from The University of Manchester, said: "It is amazing that one of the brightest stars in the infrared sky had previously gone unnoticed. We are seeing a very rare event, when a star is beginning to blow off its outer layers, as a prelude to its final explosion as a supernova."

This activity also shows that the star is likely to soon die an explosive death - it will be one of the next supernova explosions in our galaxy. Supernovae provide much-needed chemicals to the surrounding interstellar environment and the resulting shock waves can kick start the formation of new stars.

The Very Large Telescope mid-IR instrument, VISIR, captured this delicious image of the Fried Egg Nebula through three mid-infrared filters that are here coloured blue, green and red.

Giant Space Blob Glows from Within: Lyman-alpha blob LAB-1

This image shows one of the largest known single objects in the Universe, the Lyman-alpha blob LAB-1.

This picture is a composite of two different images taken with the FORS instrument on the Very Large Telescope (VLT) - a wider image showing the surrounding galaxies and a much deeper observation of the blob itself at the centre made to detect its polarisation.

The intense Lyman-alpha ultraviolet radiation from the blob appears green after it has been stretched by the expansion of the Universe during its long journey to Earth.

These new observations show for the first time that the light from this object is polarised.

This means that the giant "blob" must be powered by galaxies embedded within the cloud.

Credit: ESO/M. Hayes.

ESO VISTA Finds Star Clusters Galore

Using data from the VISTA infrared survey telescope at ESO’s Paranal Observatory, an international team of astronomers has discovered 96 new open clusters hidden by the dust in the Milky Way.

Thirty of these clusters are shown in this mosaic.

These tiny and faint objects were invisible to previous surveys, but they could not escape the sensitive infrared detectors of the world’s largest survey telescope, which can peer through the dust.

This is the first time so many faint and small clusters have been found at once. The images are made using infrared light in the following bands: J (shown in blue), H (shown in green), and Ks (shown in red).

Credit:

ESO/J. Borissova

ESO's Paranal Observatory VISTA Image: Lagoon Nebula

This new infrared view of the star formation region Messier 8, often called the Lagoon Nebula, was captured by the VISTA telescope at ESO’s Paranal Observatory in Chile.

This colour picture was created from images taken through J, H and Ks near-infrared filters, and which were acquired as part of a huge survey of the central parts of the Milky Way. The field of view is about 34 by 15 arcminutes.

Credit: ESO/VVV/Acknowledgment: Cambridge Astronomical Survey Unit

Astronomers are currently using ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA) to scour the Milky Way's central regions for variable objects and map its structure in greater detail than ever before. This huge survey is called VISTA Variables in the Via Lactea (VVV


The new infrared image presented here was taken as part of this survey. It shows the stellar nursery called the Lagoon Nebula (also known as Messier 8, see eso0936), which lies about 4000-5000 light-years away in the constellation of Sagittarius (the Archer).

Infrared observations allow astronomers to peer behind the veil of dust that prevents them from seeing celestial objects in visible light. This is because visible light, which has a wavelength that is about the same size as the dust particles, is strongly scattered, but the longer wavelength infrared light can pass through the dust largely unscathed.

VISTA, with its 4.1-metre diameter mirror - the largest survey telescope in the world - is dedicated to surveying large areas of the sky at near-infrared wavelengths deeply and quickly. It is therefore ideally suited to studying star birth.

ESO VISTA Views The Sculptor Galaxy NGC253

VISTA Views The Sculptor Galaxy


NGC 253 is one of the closest galaxies to our own. It is a bright spiral that lies about 13 million light-years from Earth in the southern constellation of Sculptor and is noted for being a starburst galaxy with very vigorous star formation and very dusty spiral arms.

In the infrared, the rich dust clouds in the galaxy's spiral arms become nearly transparent and a whole host of cool red stars that are otherwise invisible can be seen.

The VISTA infrared images were taken through Y, Z, J, Ks and narrowband filters. The field of view is about 38 by 25 arcminutes. Credit: ESO/J.Emerson/VISTA. Acknowledgment: Cambridge Astronomical Survey Unit

A spectacular new image of the Sculptor Galaxy (NGC 253) has been taken with the ESO VISTA telescope at the Paranal Observatory in Chile as part of one of its first major observational campaigns.

By observing in infrared light VISTA's view is less affected by dust and reveals a myriad of cooler stars as well as a prominent bar of stars across the central region. The VISTA image provides much new information on the history and development of the galaxy.

The Sculptor Galaxy (NGC 253) lies in the constellation of the same name and is one of the brightest galaxies in the sky. It is prominent enough to be seen with good binoculars and was discovered by Caroline Herschel from England in 1783.

NGC 253 is a spiral galaxy that lies about 13 million light-years away. It is the brightest member of a small collection of galaxies called the Sculptor Group, one of the closest such groupings to our own Local Group of galaxies. Part of its visual prominence comes from its status as a starburst galaxy, one in the throes of rapid star formation.

NGC 253 is also very dusty, which obscures the view of many parts of the galaxy (eso0902). Seen from Earth, the galaxy is almost edge on, with the spiral arms clearly visible in the outer parts, along with a bright core at its centre.

VISTA, the Visible and Infrared Survey Telescope for Astronomy, the latest addition to ESO's Paranal Observatory in the Chilean Atacama Desert, is the world's largest survey telescope. After being handed over to ESO at the end of 2009 (eso0949) the telescope was used for two detailed studies of small sections of the sky before it embarked on the much larger surveys that are now in progress.

One of these "mini surveys" was a detailed study of NGC 253 and its environment.