Category Archives: Astronomy

ESO: Public invited to watch the search for a planet around Proxima Centauri

ESO opens a new outreach program that allows the general public to follow closely the hunt for an earth-like exoplanet around the nearest star Proxima Centauri:

Follow a Live Planet Hunt!

A unique outreach campaign has been launched that will allow the general public to follow scientists from around the globe as they search for an Earth-like exoplanet around the closest star to us, Proxima Centauri. The observing campaign will run from January to April 2016 and will be accompanied by blog posts and social media updates. No one knows what the outcome will be. In the months following the observations, the scientists will analyse the data and submit the results to a peer-reviewed journal.

Pale Red Dot is an international search for an Earth-like exoplanet around the closest star to us, Proxima Centauri. It will use HARPS, attached to ESO’s 3.6-metre telescope at La Silla Observatory, as well as the Las Cumbres Observatory Global Telescope Network (LCOGT) and the Burst Optical Observer and Transient Exploring System (BOOTES).  It will be one of the few outreach campaigns allowing the general public to witness the scientific process of data acquisition in modern observatories. The public will see how teams of astronomers with different specialities work together to collect, analyse  and interpret data, which may or may not be able to confirm the presence of an Earth-like planet orbiting our nearest neighbour . The outreach campaign consists of blog posts and social media updates on the Pale Red Dot Twitter account and using the hashtag #PaleRedDot. For more information visit the Pale Red Dot website: http://www.palereddot.org
Pale Red Dot is an international search for an Earth-like exoplanet around the closest star to us, Proxima Centauri. It will use HARPS, attached to ESO’s 3.6-metre telescope at La Silla Observatory, as well as the Las Cumbres Observatory Global Telescope Network (LCOGT) and the Burst Optical Observer and Transient Exploring System (BOOTES). It will be one of the few outreach campaigns allowing the general public to witness the scientific process of data acquisition in modern observatories. The public will see how teams of astronomers with different specialities work together to collect, analyse  and interpret data, which may or may not be able to confirm the presence of an Earth-like planet orbiting our nearest neighbour . The outreach campaign consists of blog posts and social media updates on the Pale Red Dot Twitter account and using the hashtag #PaleRedDot. For more information visit the Pale Red Dot website: http://www.palereddot.org

At a distance of just 4.2 light-years from the Sun, and located in the constellation of Centaurus, Proxima Centauri is the closest known star to the Sun. Previous observations have provided tantalising, but weak hints of a small companion orbiting this red dwarf star, but this new campaign will make a more sensitive search for the telltale wobbles in the dwarf star’s orbital motion that might reveal the presence of an Earth-like orbiting planet.

Observations will be made with the High Accuracy Radial velocity Planet Searcher (HARPS), attached to ESO’s 3.6-metre telescope at La Silla Observatory. The HARPS data will be complemented by images from an assortment of robotic telescopes located across the world [1].

The telescopes that comprise the Burst Optical Observer and Transient Exploring System (BOOTES) and the Las Cumbres Observatory Global Telescope Network (LCOGT) will support the search by measuring the brightness of Proxima Centauri every night during the two and a half month long project. These observations will help astronomers determine whether any detected wobbles in the star’s motion are caused by features on its turbulent surface or by an orbiting planet.

Once the data have been collected by the various telescopes, astronomers can start their analysis. In the following months, their research methods and conclusions will be described in a paper submitted to a peer-reviewed scientific journal. When the scientific community has validated the research, the results will be published, concluding a long and substantial programme of scientific research.

Apart from following the scientific observations as they arrive, the Pale Red Dot outreach campaign [2] gives the public the opportunity to see how science is done in modern observatories, and how teams of astronomers with different specialities work together to collect, analyse and interpret data, which may or may not be able to confirm the presence of an Earth-like planet orbiting our nearest neighbour.

We are taking a risk to involve the public before we even know what the observations will be telling us  — we cannot analyse the data and draw conclusions in real time. Once we publish the paper summarising the findings it’s entirely possible that we will have to say that we have not been able to find evidence for the presence of an Earth-like exoplanet around Proxima Centauri. But the fact that we can search for such small objects with such extreme precision is simply mind-boggling,” said Guillem Anglada-Escude, the Project Coordinator.

We want to share the excitement of the search with people and show them how science works behind the scenes, the trial and error process and the continued efforts that are necessary for the discoveries that people normally hear about in the news. By doing so, we hope to encourage more people towards STEM [3] subjects and science in general,” adds Guillem.

The Pale Red Dot outreach campaign will illuminate the often unseen side of planet hunting with background articles and through social media. A bustling array of blog posts on many topics — including planet-hunting techniques, ESO’s European Extremely Large Telescope (E-ELT), and the lives of stars — are planned, written by the astronomers, scientists and engineers from the observatories involved, as well as science writers, observers and other experts in the field.

There will be daily social media updates, briefing the public on how the observations are going and any events taking place at the three observatories involved. To receive updates, people are invited to follow the Pale Red Dot Twitter account and the hashtag #PaleRedDot.

The name of the campaign was inspired by the famous “pale blue dot” image of the Earth, taken in 1990 by Voyager 1 on its way to interstellar space. The phrase was later used by Carl Sagan for his essay, Pale Blue Dot: A Vision of the Human Future in Space. As Proxima Centauri is a red dwarf star, astronomers expect that an exoplanet orbiting it will appear reddish. At the same time, just as Voyager’s image of Earth was a remarkable achievement for humanity, finding an Earth-like exoplanet around the closest star to us would be a another step towards answering humanity’s biggest question: Are we alone?

The Pale Red Dot campaign will begin in earnest on 15 January 2016 with observations commencing just three days later from ESO’s La Silla Observatory, situated at the edge of the Chilean Atacama Desert, and continuing until the first week of April. All of the scientific data obtained as part of the project are expected to become publicly available for all to exploit in late 2016.

Notes

[1] The team of astronomers leading the observations and outreach campaign are: Guillem Anglada-Escude, Gavin Coleman, John Strachan (Queen Mary University of London, UK), James Jenkins  (Universidad de Chile, Chile), Cristina Rodriguez-Lopez, Zaira M. Berdinas, Pedro J. Amado (Instituto de Astrofisica de Andalucia/CSIC), Julien Morin (Universite de Montpellier, France), Mikko Tuomi (Centre for Astrophysics Research/University of Hertfordshire, UK), Yiannis Tsapras (Heidelberg/LCOGT, Astronomisches Rechen-Institut – Heidelberg & LCOGT) and Christopher J. Marvin (University of Goettingen).

[2] The outreach campaign is coordinated by the project team with support from the outreach departments of ESO, Queen Mary University of London, Instituto de Astrofisica de Andalucia/CSIC, Universite de Montpellier, University of Goettingen, Universidad de Chile and Las Cumbres Observatory Global Telescope Network.

[3] STEM, Science, Technology, Engineering and Mathematics.

ESO: ALMA peers into the hottest of the Hot DOG quasars

The latest ESO (European Southern Observatory) report:

The Turbulent Birth of a Quasar

The most luminous galaxy known in the Universe — the quasar W2246-0526, seen when the Universe was less than 10% of its current age — is so turbulent that it is in the process of ejecting its entire supply of star-forming gas, according to new observations with the Atacama Large Millimeter/submillimeter Array (ALMA).

Artist impression of W2246-0526, a single galaxy glowing in infrared light as intensely as 350 trillion suns. It is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with ALMA.
Artist impression of W2246-0526, a single galaxy glowing in infrared light as intensely as 350 trillion suns. It is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with ALMA.

Quasars are distant galaxies with very active supermassive black holes at their centres that spew out powerful jets of particles and radiation. Most quasars shine brightly, but a tiny fraction [1] of these energetic objects are of an unusual type known as Hot DOGs, or Hot, Dust-Obscured Galaxies, including the galaxy WISE J224607.57-052635.0 [2], the most luminous known galaxy in the Universe.

For the first time, a team of researchers led by Tanio Díaz-Santos of the Universidad Diego Portales in Santiago, Chile, has used the unique capabilities of ALMA [3] to peer inside W2246-0526 and trace the motion of ionised carbon atoms between the galaxy’s stars.

“Large amounts of this interstellar material were found in an extremely turbulent and dynamic state, careening throughout the galaxy at around two million kilometres per hour,” explains lead author Tanio Díaz-Santos.

The astronomers believe that this turbulent behaviour could be linked to the galaxy’s extreme luminosity. W2246-0526 blasts out as much light as roughly 350 trillion Suns. This startling brightness is powered by a disc of gas that is superheated as it spirals in on the supermassive black hole at the galaxy’s core. The light from the blazingly bright accretion disc in the centre of this Hot DOG does not escape directly, it is absorbed by a surrounding thick blanket of dust, which re-emits the energy as infrared light [4].

This powerful infrared radiation has a direct and violent impact on the entire galaxy. The region around the black hole is at least 100 times more luminous than the rest of the galaxy combined, thus releasing intense yet localised radiation in W2246-0526 that is exerting tremendous pressure on the entire galaxy [5].

“We suspected that this galaxy was in a transformative stage of its life because of the enormous amount of infrared energy,” said co-author Peter Eisenhardt, Project Scientist for WISE at NASA’s Jet Propulsion Laboratory in Pasadena, California.

“ALMA has now shown us that the raging furnace in this galaxy is making the pot boil over,” adds Roberto Assef, also from Universidad Diego Portales and leader of the ALMA observations.

If these turbulent conditions continue, the intense infrared radiation would boil away all of the galaxy’s interstellar gas. Models of galaxy evolution based on the new ALMA data indicate that the interstellar gas is already being ejected from the galaxy in all directions.

“If this pattern continues, it is possible that W2246 will eventually mature into a more traditional quasar,” concludes Manuel Aravena, also from the Universidad Diego Portales. “Only ALMA, with its unparalleled resolution, can allow us to see this object in high definition and fathom such an important episode in the life of this galaxy.”

Notes

[1] Only one of every 3000 quasars observed are classified as Hot DOGs.

[2] The full name of this remarkable object is WISE J224607.57-052635.0, it was found by NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft and the rest of the name gives the precise location of the quasar on the sky.

[3] ALMA is uniquely capable of detecting the faint, millimetre-wavelength light naturally emitted by atomic carbon.

[4] Because of the expansion of the Universe the infrared radiation from W2246-0526 is redshifted to longer millimetre wavelengths — where ALMA is very sensitive — when it is observed from Earth.

[5] In most other quasars this ratio is much more modest. This process of mutual interaction between the central black hole of a galaxy and the rest of its material is known to astronomers as feedback.

More information

This research was presented in a paper “The Strikingly Uniform, Highly Turbulent Interstellar Medium of The Most Luminous Galaxy in the Universe”, by T. Díaz-Santos et al., and will be published in the journal Astrophysical Journal Letters.

The team is composed of T. Díaz-Santos (Universidad Diego Portales, Santiago, Chile), R. J. Assef (Universidad Diego Portales, Santiago, Chile), A. W. Blain (University of Leicester, UK) , C.-W. Tsai (Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA) , M. Aravena (Universidad Diego Portales, Santiago, Chile), P. Eisenhardt (Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA), J. Wu (University of California Los Angeles, California, USA), D. Stern (Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA) and C. Bridge (Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA).

ESO: Combining light from multiple telescopes forms 200 meter virtual telescope

A new report from ESO (European Southern Observatory):

First Light For Future Black Hole Probe

Zooming in on black holes is the main mission for the newly installed instrument GRAVITY at ESO’s Very Large Telescope in Chile. During its first observations, GRAVITY successfully combined starlight using all four Auxiliary Telescopes. The large team of European astronomers and engineers, led by the Max Planck Institute for Extraterrestrial Physics in Garching, who designed and built GRAVITY, are thrilled with the performance. During these initial tests, the instrument has already achieved a number of notable firsts. This is the most powerful VLT Interferometer instrument yet installed.

As part of the first observations with the new GRAVITY instrument the team looked closely at the bright, young stars known as the Trapezium Cluster, located in the heart of the Orion star-forming region. Already, from these first data, GRAVITY made a discovery: one of the components of the cluster (Theta1 Orionis F, lower left) was found to be a double star for the first time. The brighter double star Theta1 Orionis C (lower right) is also well seen. The background image comes from the ISAAC instrument on ESO's Very Large Telescope. The views of two of the stars from GRAVITY, shown as inserts, reveal far finer detail than could be detected with the NASA/ESA Hubble Space Telescope.
As part of the first observations with the new GRAVITY instrument the team looked closely at the bright, young stars known as the Trapezium Cluster, located in the heart of the Orion star-forming region. Already, from these first data, GRAVITY made a discovery: one of the components of the cluster (Theta1 Orionis F, lower left) was found to be a double star for the first time. The brighter double star Theta1 Orionis C (lower right) is also well seen. The background image comes from the ISAAC instrument on ESO’s Very Large Telescope. The views of two of the stars from GRAVITY, shown as inserts, reveal far finer detail than could be detected with the NASA/ESA Hubble Space Telescope.

The GRAVITY instrument combines the light from multiple telescopes to form a virtual telescope up to 200 metres across, using a technique called interferometry. This enables the astronomers to detect much finer detail in astronomical objects than is possible with a single telescope.

Since the summer of 2015, an international team of astronomers and engineers led by Frank Eisenhauer (MPE, Garching, Germany) has been installing the instrument in specially adapted tunnels under the Very Large Telescope at ESO’s Paranal Observatory in northern Chile [1]. This is the first stage of commissioning GRAVITY within the Very Large Telescope Interferometer (VLTI). A crucial milestone has now been reached: for the first time, the instrument successfully combined starlight from the four VLT Auxiliary Telescopes [2].

As part of the first observations with the new GRAVITY instrument the team looked closely at the bright, young stars known as the Trapezium Cluster, located in the heart of the Orion star-forming region. Already, from these first data, GRAVITY made a discovery: one of the components of the cluster (Theta1 Orionis F) was found to be a double star for the first time.

This zoom video starts with a broad view of the famous constellation of Orion (The Hunter) and then shows successively more detailed images of the region with different telescopes. The final view from GRAVITY reveals far finer detail around one of the fainter cluster stars than could be detected even with the NASA/ESA Hubble Space Telescope.

Credit: ESO/M. McCaughrean/GRAVITY consortium, Nick Risinger (skysurvey.org),  Music: Johan B. Monell (www.johanmonell.com).

“During its first light, and for the first time in the history of long baseline interferometry in optical astronomy, GRAVITY could make exposures of several minutes, more than a hundred times longer than previously possible,” commented Frank Eisenhauer. “GRAVITY will open optical interferometry to observations of much fainter objects, and push the sensitivity and accuracy of high angular resolution astronomy to new limits, far beyond what is currently possible.”

As part of the first observations the team looked closely at the bright, young stars known as the Trapezium Cluster, located in the heart of the Orion star-forming region. Already, from these first commissioning data, GRAVITY made a small discovery: one of the components of the cluster was found to be a double star [3].

The key to this success was to stabilise the virtual telescope for long enough, using the light of a reference star, so that a deep exposure on a second, much fainter object becomes feasible. Furthermore, the astronomers also succeeded in stabilising the light from four telescopes simultaneously — a feat not achieved before.

Zooming in on black holes is the main mission for the newly installed instrument GRAVITY at ESO’s Very Large Telescope in Chile. During its first observations, GRAVITY successfully combined starlight using all four Auxiliary Telescopes.
Zooming in on black holes is the main mission for the newly installed instrument GRAVITY at ESO’s Very Large Telescope in Chile. During its first observations, GRAVITY successfully combined starlight using all four Auxiliary Telescopes.

GRAVITY can measure the positions of astronomical objects on the finest scales and can also perform interferometric imaging and spectroscopy [4]. If there were buildings on the moon, GRAVITY would be able to spot them. Such extremely high resolution imaging has many applications, but the main focus in the future will be studying the environments around black holes.

In particular, GRAVITY will probe what happens in the extremely strong gravitational field close to the event horizon of the supermassive black hole at the centre of the Milky Way — which explains the choice of the name of the instrument. This is a region where behaviour is dominated by Einstein’s theory of general relativity. In addition, it will uncover the details of mass accretion and jets — processes that occur both around newborn stars (young stellar objects) and in the regions around the supermassive black holes at the centres of other galaxies. It will also excel at probing the motions of binary stars, exoplanets and young stellar discs, and in imaging the surfaces of stars.

So far, GRAVITY has been tested with the four 1.8-metre Auxiliary Telescopes. The first observations using GRAVITY with the four 8-metre VLT Unit Telescopes are planned for later in 2016.

The GRAVITY consortium is led by the Max Planck Institute for Extraterrestrial Physics, in Garching, Germany. The other partner institutes are:

  • LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, Meudon, France
  • Max Planck Institute for Astronomy, Heidelberg, Germany
  • 1. Physikalisches Institut, University of Cologne, Cologne, Germany
  • IPAG, Université Grenoble Alpes/CNRS, Grenoble, France
  • Centro Multidisciplinar de Astrofísica, CENTRA (SIM), Lisbon and Oporto, Portugal
  • ESO, Garching, Germany

Notes

[1] The VLTI tunnels and beam-combining room have recently undergone significant construction work to accommodate GRAVITY as well as to prepare for other future instruments.

[2] It would be more accurate to call this step “first fringes” as the milestone was the first successful combination of light from the different telescopes so that the beams interfered and fringes were formed and recorded.

[3] The newly discovered double star is Theta1 Orionis F, and the observations were made using the nearby brighter star Theta1 Orionis C as the reference.

[4] GRAVITY aims to measure the positions of objects on scales of order ten microarcseconds, and perform imaging with four milliarcsecond resolution.

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 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. 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 a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Dwarf galaxy spotted by Australian “strongman” amateur astrophotographer

Australian Michael Sidonio is “a competitive strongman” and also a first rate amateur astrophotographer who spotted a previously unheralded dwarf galaxy:

From his gallery:

[]
NGC 253-dw2 Deep Discovery Image – Credits Michael Sidonio

As part of a professional team lead by Aaron J. Romanowsky and David Martinez-Delgardo, this is my first involvement in a scientific discovery and my first scientific paper too. The paper was accepted for publication in the Monthly Notices of The Royal Astronomical Society on Monday 21 Dec 2015.

The galaxy, in this case a Dwarf Spheroidal, was first discovered in a deep image I did of NGC 253 using my Orion Optics UK AG12 a 12″ F3.8 corrected Newtonian. This was then subsequently followed up by deep exposures by the CHART 32 team with their 32″ F7 corrected Cassegrain telescope at Cerro Tololo and then finally the Suprime-Cam on the 8m Subaru telescope was used, in sub arc sec seeing, to resolve stars and confirm the discovery and galaxy classification.

So to discover something so faint and so close to such a well researched galaxy like NGC 253 is extra special and the new galaxy is called NGC 253-dw2

The last line of the abstract is very encouraging too: “We also note the continued efficacy of small telescopes for making big discoveries”

Afghan astronomy fans take big risks to view the night sky

While astronomy enthusiasts in many countries complain about inconveniences such as light pollution and cloudy weather, the members of the Afghanistan Astronomy Association must overcome truly dangerous challenges to view the night sky with their telescopes: Amateur Afghan Astronomy Is Risky Business – Newsweek.

Afghanistan’s war has taken a devastating toll on civilians: death, displacement, poverty. But it also affects lives in unexpected ways. For the country’s small band of amateur astronomers, exploring the universe’s deepest corners is a risk they now rarely take. The increasing encroachment of the Taliban, criminal gangs and aggressive police checkpoints means they now limit observations to the outskirts of Kabul city or their rooftops. “The places where there are the darkest skies, almost all those places are insecure,” says Ibrahim Amiri, 26, one of the youngest members of the Afghanistan Astronomy Association.

His eyes shine as he describes the high altitude and low light pollution of Badakhshan in the north and the open horizons of Kandahar in the south, both perfect regions for stargazing. “But we could be attacked by anyone [there]. Not just Taliban or ISIS, but even the local people,” he explains. “Afghans, especially villagers, are usually not very comfortable with people they don’t know or things they don’t understand.”

[]
Yunos Bakshi standing with one of his telescopes in Kabul, Afghanistan.
Bakshi is the founder of Afghanistan’s first Astronomy Association.
Image by Jeffrey E. Stern. Afghanistan, 2013.