Starship Asterisk*

Credit: ESO/SPECULOOS

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If you had a brand new state-of-the-art telescope facility, what would you look at first? Researchers at the SPECULOOS Southern Observatory — which comprises four small telescopes, each with a 1-metre primary mirror — chose to view the Lagoon Nebula. This magnificent picture is the result, and is one of the SPECULOOS’ first ever observations. The nebula is a cloud of dust and gas in our galaxy where new stars are being born, and is found roughly 5000 light-years from us.

This striking image is made even more impressive by the fact that the SPECULOOS isn’t actually designed to study nebulae. The name says it all — SPECULOOS, the Search for habitable Planets EClipsing ULtra-cOOl Stars. In other words, the primary mission of this telescope facility is to find Earth-like planets orbiting faint nearby stars. The candidates it discovers will be passed over to larger telescopes, such as ESO’s forthcoming Extremely Large Telescope (ELT), to be studied in more detail.

SPECULOOS is located at ESO’s Paranal Observatory in the Atacama Desert of Chile, taking full advantage of the location’s dark skies, ideal atmospheric conditions, and the support systems ESO has there, from telescope infrastructure to staff accommodation. It will have a partner, the SPECULOOS Northern Observatory, in the Canary Islands, which will hunt for planets in the northern skies not visible from Chile. Together they promise to vastly expand our knowledge of the exoplanets in our neighbourhood.

Image Credit: ESA/Hubble & NASA, A. Adamo et al

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Located in the constellation of Hercules, about 230 million light-years away, NGC 6052 is a pair of colliding galaxies. They were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding. This particular image of NGC 6052 was taken using the Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope.

A long time ago gravity drew the two galaxies together into the chaotic state we now observe. Stars from within both of the original galaxies now follow new trajectories caused by the new gravitational effects. However, actual collisions between stars themselves are very rare as stars are very small relative to the distances between them (most of a galaxy is empty space). Eventually things will settle down and one day the two galaxies will have fully merged to form a single, stable galaxy.

Our own galaxy, the Milky Way, will undergo a similar collision in the future with our nearest galactic neighbour, the Andromeda Galaxy. Although this is not expected to happen for around 4 billion years so there is nothing to worry about just yet.

This object was previously observed by Hubble with its old WFPC2 camera. That image was released in 2015.

starsurfer wrote: ↑Fri Mar 08, 2019 11:48 am IC 1311
https://www.hansonastronomy.com/ic-1311-in-cygnus
Copyright: Mark Hanson
IC1311.jpg

Image Credit: ESO/A Klotz (TAROT)

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On the night of 20 January 2019 Coquimbo, Chile shook with the force of a magnitude 6.7 earthquake. Although Coquimbo lies 90 kilometres from ESO’s La Silla Observatory, its effects were far from unnoticed.

This unique image shows the earthquake as recorded by the Rapid Action Telescope for Transient Objects (TAROT), a telescope designed to monitor gamma-ray bursts.

On the night in question, TAROT was imaging geostationary satellites, which look like static points in the sky as seen from a telescope on the ground. As a result, the stars are recorded as trails, as the Earth rotates on its axis during the exposure. In this picture, three 10 second images, taken in rapid succession on the night of the earthquake, have been overlaid.

The first image (left) was started 41 seconds after the start of the earthquake, and the last (right) finishes about 100 seconds after the beginning of the earthquake. Each star is seen three times as the earthquake shakes the telescope and blurs its view of the night sky. The effect of the earthquake gradually weakens with time (towards the right of the image).

The recording on the image here is similar to measurements recorded by seismographs on a roll of paper.

Image Credit: ESA/Hubble & NASA, J. E. Grindlay et al.

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This Hubble Picture of the Week shows Messier 28, a globular cluster in the constellation of Sagittarius (The Archer), in jewel-bright detail. It is about 18 000 light-years away from Earth.

As its name suggests, this cluster belongs to the Messier catalogue of objects — however, when astronomer Charles Messier first added Messier 28 to his list in 1764, he catalogued it incorrectly, referring to it as a “[round] nebula containing no star”. While today we know nebulae to be vast, often glowing clouds of interstellar dust and ionised gases, until the early twentieth century a nebula represented any astronomical object that was not clearly localised and isolated. Any unidentified hazy light source could be called a nebula. In fact, all 110 of the astronomical objects identified by Messier were combined under the title of the Catalogue of Nebulae and Star Clusters. He classified many objects as diverse as star clusters and supernova remnants as nebulae. This includes Messier 28, pictured here — which, ironically, is actually a star cluster.

Messier’s mistake is understandable. Whilst Messier 28 is easily recognisable as a globular stellar cluster in this image, it is far less recognisable from Earth. Even with binoculars it is only visible very faintly, as the distorting effects of the Earth’s atmosphere reduce this luminous ancient cluster to a barely visible smudge in the sky. One would need larger telescopes to resolve single stars in Messier 28. Fortunately, from space Hubble allows Messier 28 to be seen in all its beauty — far more than a faint, shapeless, nebulous cloud.

Credit: ESO Cosmic Gems

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It’s impossible to miss the star in this ESO Picture of the Week — beaming proudly from the centre of the frame is the massive multiple star system Tau Canis Majoris, the brightest member of the Tau Canis Majoris Cluster (NGC 2362) in the eponymous constellation of Canis Major (The Great Dog). Tau Canis Majoris aside, the cluster is populated by many young and less attention-seeking stars that are only four or five million years old, all just beginning their cosmic lifetimes.

The Tau Canis Majoris Cluster is an open cluster — a group of stars born from the same molecular cloud. This means that all of the cluster’s inhabitants share a common chemical composition and are loosely bound together by gravity. Having been born together, they make an ideal stellar laboratory to test theories of stellar evolution, the chain of events that leads from a star’s birth in a cool, dense cloud of gas through to its eventual death.

Though the stars in this image were all created at the same time, their various different masses mean they will lead very different lives. As Tau Canis Majoris is one of the most massive and short-lived types of star, it will burn through its nuclear fuel long before its smaller companions, which will keep on shining for billions of years.

This image was created as part of the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.