Probing the Spiderweb Galaxy Cluster (MRC 1138-262) Yields Surprising Data

A galaxy cluster is composed of smaller galaxies held together by gravity. It is the largest object found in the Universe.

Using the APEX telescope, astronomers probed the Spiderweb Galaxy which is a galaxy cluster 10.6 billion light years away. Formed by smaller galaxies, the Spiderweb Galaxy (also known as MRC 1138-262) has been studied for twenty years. It has been observed that the object contains a supermassive black hole and is a powerful source of radio waves.

The data from the observation has surprised scientists with their discovery of the formation of the stars in the galaxy cluster taking place. They have noted that instead of the stars being formed from the filaments of the cluster, APEX data has shown that the star formation region is concentrated in one area and not even centered on the galaxy cluster itself.

The Spiderweb Galaxy contains a supermassive black hole and is a powerful source of radio waves — which is what led astronomers to notice it in the first place. The object has thick dust clouds which the LABOCA camera on the APEX telescope can see through.

APEX Telescope To See Further into the Universe with ArTeMiS Camera

The Atacama Pathfinder Experiment (APEx) telescope used to capture detailed images of the Universe got a significant boost with the addition of the ArTeMiS camera. Artemis will help APEX take images faster and with higher pixel resolutions.

The ArTeMiS camera is a large bolometer camera in the submillimeter range on APEX. A bolometer is a device that is used to measure infrared, or heat, radiation. ARTEMIS stands for Architectures de bolomètres pour des Télescopes à grand champ de vue dans le domaine sub-Millimétrique au Sol which in English translates to the Bolometer arrays for wide-field submillimetre ground-based telescopes.

The image above is the Cat's Paw Nebula in the southern constellation of Scorpius (The Scorpion) as captured by the Artemis camera. This detailed image is significantly clearer than previous images captured by the APEX telescope alone.

The APEX project is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and the Eurpean Southern Observatory (ESO). Operation of APEX at Chajnantor is entrusted to ESO.

Reflection Nebula NGC 1999 in Orion Imaged By APEX LABOCA Camera

A new image from the Atacama Pathfinder Experiment (APEX) telescope in Chile shows a beautiful view of clouds of cosmic dust in the region of Orion. While these dense interstellar clouds seem dark and obscured in visible-light observations, APEX’s LABOCA camera can detect the heat glow of the dust and reveal the hiding places where new stars are being formed. The image shows the region around the reflection nebula NGC 1999 in visible light, with the APEX observations overlaid in brilliant orange tones that seem to set the dark clouds on fire.
Credit: ESO/APEX (MPIfR/ESO/OSO)/T. Stanke et al./Digitized Sky Survey 2

A nebula is a cloud of dust and gas in outer space. These are where stars are formed. The gas and dust in the cloud start to collapse into each other gaining mass and density until it forms a star (which takes millions of years). Nebula is latin for cloud.

There are different types of nebulae such as Emission nebulae, reflection nebulae, dark nebulae, planetary nebulae and supernova remnants.

Some nebulae emit light because of the surrounding gas getting ionized. Dark nebulae are nebulae that do not emit light and appear as a dark spot or cloud in the sky.

A reflection nebula, just like NGC 1999, is a nebula that reflects light from nearby stars. It is similar to a dark nebula but they are less dense than dark nebula which allows the reflected light to scatter.

The boundaries of a reflection nebula is not defined by the size of the dust cloud but rather the area over which their brightness remains above the point of detection.

APEX Space Telescope Linked To Two Others For Sharpest Observation of Quasar 3C 279

An international team of astronomers has observed the heart of a distant quasar with unprecedented sharpness, two million times finer than human vision. The observations, made by connecting the Atacama Pathfinder Experiment (APEX) telescope ^[1] to two others on different continents for the first time, is a crucial step towards the dramatic scientific goal of the “Event Horizon Telescope” project^[2]: imaging the supermassive black holes at the centre of our own galaxy and others.

Astronomers connected APEX, in Chile, to the Submillimeter Array (SMA)^[3] in Hawaii, USA, and the Submillimeter Telescope (SMT)^[4] in Arizona, USA. They were able to make the sharpest direct observation ever^[5], of the centre of a distant galaxy, the bright quasar 3C 279, which contains a supermassive black hole with a mass about one billion times that of the Sun, and is so far from Earth that its light has taken more than 5 billion years to reach us. APEX is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and ESO. APEX is operated by ESO.

The telescopes were linked using a technique known as Very Long Baseline Interferometry (VLBI). Larger telescopes can make sharper observations, and interferometry allows multiple telescopes to act like a single telescope as large as the separation — or “baseline” — between them. Using VLBI, the sharpest observations can be achieved by making the separation between telescopes as large as possible. For their quasar observations, the team used the three telescopes to create an interferometer with transcontinental baseline lengths of 9447 km from Chile to Hawaii, 7174 km from Chile to Arizona and 4627 km from Arizona to Hawaii. Connecting APEX in Chile to the network was crucial, as it contributed the longest baselines.

The Reflection Nova Messier 78 and the Atacama Pathfinder Experiment telescope (APEX)

APEX Telescope in Chile

The Atacama Pathfinder Experiment telescope (APEX) is a 12 meter diameter telescope. Operated by the European Southern Observatory (ESO), the telescope operates at millimeter and sub-millimeter wavelengths which are wavelengths between infrared light and radio waves.

The APEX telescope is situated at the Chajnantor plateau in the Atacama region of Chile. With an elevation of 5100 meters (3.17 miles), it is one of the highest observatory sites on Earth.

APEX is a 12-metre diameter telescope, operating at millimetre and submillimetre wavelengths — between infrared light and radio waves. Submillimetre astronomy opens a window into the cold, dusty and distant Universe, but the faint signals from space are heavily absorbed by water vapour in the Earth's atmosphere. Chajnantor is an ideal location for such a telescope, as the region is one of the driest on the planet and is more than 750 m higher than the observatories on Mauna Kea, and 2400 m higher than the Very Large Telescope (VLT) on Cerro Paranal.

APEX is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and ESO. Operation of APEX at Chajnantor is entrusted to ESO. APEX is a pathfinder for the next-generation submillimetre telescope, the Atacama Large Millimeter/submillimeter Array (ALMA), which is being built and operated on the same plateau.

Messier 78

In the constellation of Orion, 1350 light years away, lies the reflection nebula, Messier 78. Reflection nebulas (nebulae) are clouds of dust which reflect the light of a nearby star or stars. Messier 78 is a fine example of a reflection nebula.

The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO’s Hidden Treasures 2010 astrophotography competition with his image of this stunning object.
Photo: ESO