- RECENT HEADLINES
- Liverpool Telescope helps find source of high energy neutrinos
- OPTICON Call for Proposals for Semester 2019A
- Exploring new astronomical database technologies — a collaborative workshop between LJMU and Thailand
- New Robotic Telescope workshop held in Liverpool
- Interstellar visitor tracked with LT
- Liverpool Telescope project shortlisted for Research Project of the Year
- Spectacular pictures added to LT Picture Gallery
- New Filter for RISE
The Liverpool Telescope contributed to the multiwavelength follow-up campaign of the blazar TXS 0506+056, published last month in Science (IceCube Collaboration, Science, 2018, 361, 1378: arXiv:1807.08816). The campaign was prompted by the detection on 22 September 2017 of a neutrino with an energy of ~290 tera electron volts, by the IceCube Neutrino Observatory at the South Pole. The observatory consists of thousands of sensors buried in a cubic kilometre of Antarctic ice, designed to detect the Cherenkov radiation from charged particles.
The neutrino detection was consistent with the gamma-ray blazar TXS 0506+056, which was observed to be in a flaring state at the time. The extensive campaign which followed involved observations from across the electromagnetic spectrum, with the Liverpool Telescope contributing early spectra of the galaxy obtained with its SPRAT classification spectrograph.
The observation of a neutrino in spatial coincidence with a gamma-ray–emitting blazar during an active phase suggests that blazars are a source of high-energy neutrinos, and moreover this event marks the beginning of the era of neutrino astronomy, a 'multimessenger' method combining both electromagnetic and non-electromagnetic means of observation.
Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the famous supernova 1987A: the era of neutrino astronomy will hopefully reveal the sources of high energy cosmic rays in the Universe, since neutrinos, gamma-rays and cosmic rays should all be produced by the same physical processes.
The latest call for proposals for telescopes supported by the OPTICON Trans-National Access programme has just been released. The LT is one of the telescopes in this programme, and complete instructions on how to apply to OPTICON for time on the LT are given in the full text of the call, presented below:
The ARI-NARIT joint development team. Left to right: Bovornpratch Vijarnwannaluk, Pathompong Butpan, Utane Sawangwit, Marco Lam, Andrzej Piascik, Chris Copperwheat, Robert Smith, Iain Steele.
Liverpool John Moores University (LJMU) Astrophysics Research Institute (ARI) recently hosted a 3-week Newton Fund collaboration workshop with the National Astronomical Research Institute of Thailand (NARIT). LJMU and NARIT both own and operate their own 2-metre class telescopes: LJMU's Liverpool Telescope, and NARIT's Thai National Observatory.
Both institutes developed a common interest in exploiting new technologies for data management and archiving. These new systems will be used for their existing telescope facilities, and also for LJMU's proposed 4-metre class New Robotic Telescope (commonly known as "Liverpool Telescope 2"), on which NARIT is collaborating.
The joint development team compared the feasibility of using PostgreSQL (PSQL) and Elasticsearch (ES) as the core engine of a new archive system for astronomical data. LJMU developers Dr Marco Lam and Dr Andrzej Piascik worked with Bovornpratch Vijarnwannaluk and Pathompong Butpan from NARIT, to compare the efficiency of an ES search engine to that of a conventional relational database.
In the final week, Dr Utane Sawangwit from NARIT also joined us to conclude the project. This entailed the production of a complete prototype web front end for the demonstrator archives. A poster paper describing the work was presented in the Software Session of the European Week of Astronomy and Space Science 2018. A joint research paper will also be presented at the June SPIE 2018 Astronomical Telescopes conference in Austin, Texas.
LJMU staff were joined by representatives from the Instituto de Astrofísica de Canarias, the National Astronomical Research Institute of Thailand, and by videolink the National Astronomical Observatory of China.
On the first day, following a tour of the Astrophysics Research Institute, the focus was on the new science the telescope will enable, with a series of presentations covering all of the major topics within the NRT science case. This was followed by a workshop dinner. As well as the delegates, the dinner was attended by Prof. Ahmed Al-Shamma'a, the Dean of the Faculty of Engineering and Technology; and Prof. Robin Leatherbarrow, the Pro Vice-Chancellor for Research.
On day two, the focus was on the new technologies needed to build the telescope. Each group presented an overview of their technical capabilities, and then a lively debate was held over the various parameters of the NRT design. The meeting concluded with a round table discussion on the building and formalising of the funding consortium. This was an extremely fruitful exercise, being the first time the partners and current prospective partners have come together to discuss a way forward for the project, rather than meeting individually.
With the Lead Engineer and Project Manager for the NRT joining the LT group, and further project office recruitments underway in both Liverpool and Spain, this is an exciting time for us all as we move closer towards realising the goal of building the world's largest robotic telescope!
Animation of 'Oumuamua (dot, circled) moving against background stars, made from frames obtained by the Liverpool Telescope on 26 October 2017.
Credit: Alan Fitzsimmons.
The interstellar object currently exiting the Solar System has finally been named as ‘Oumuamua, Hawaiian for "reach out for" (‘Ou) and "very first/in advance of" (mua mua). Thus the name "reflects the way this object is like a scout or messenger sent from the distant past".
‘Oumuamua was first detected on 19th October by Robert Weryk at the Institute for Astronomy at the University of Hawaii using data from the Pan-STARRS telescope on Mauna Kea in Hawaii. After a few nights of routine observation, preliminary calculations showed it to be on an open-ended hyperbolic orbit, i.e. to have entered the Solar System from interstellar space. Moreover, it had already made its closest approach to the Sun some weeks earlier and was now receding rapidly from the inner solar system.
Previously, the only other interstellar emissaries known to exist were a handful of microscopic dust particles discovered in 2014 in an aerogel dust collector brought back to Earth by the comet sample return mission Stardust. ‘Oumuamua on the other hand is estimated to be approximately 160 metres in diameter.
As this object is the first interstellar visitor observed, and was also rapidly becoming fainter as days passed, it become a race against time to observe ‘Oumuamua as much as possible before it passed out of detection range forever.
Alerts were circulated around the global astronomical community in the early hours of 25th October. Later that day veteran LT user Alan Fitzsimmons of Queens University Belfast requested a priority observation via the LT's database, and that night the LT began observing ‘Oumuamua. The animated gif of Fitzsimmons' 26th October observations is at the top of this page. Below is imagery from the William Herschel Telescope taken by Fitzsimmons on 28th Oct.
|‘Oumuamua (dot, centre) tracked against background stars by the William Herschel Telescope on 28th October.
Credit: Alan Fitzsimmons.
As a result of the efforts of astronomers around the world, not only has the orbit been definitively pinned down, but also aspects of its physical nature have been revealed. It's approximately 160 metres in diameter (assuming it reflects 10% of the sunlight falling on it), has a spin rate of possibly 6 hours, and has no cometary activity, despite getting as close as 0.25 AU from the Sun. Spectra are featureless and show its colour is red like a Kuiper Belt Object. That plus the lack of comet activity imply ‘Oumuamua must have spent so much time in the inner warmer reaches of its home star system that all volatiles had already disappeared by the time it left for interstellar space.
‘Oumuamua is now leaving the Solar System in the direction of the constellation Pegasus. By the time it leaves the Sun's influence, it will still be moving at over 26 kilometres per second, faster than any human-built spacecraft currently exiting our solar system. Efforts to trace its original stellar system, and where it might be headed in aeons to come, have so far been unsuccessful (the tiny errors in trajectory remaining after such a short arc of observations build up dramatically over millions of years). Given how relatively uncrowded stars are this far from galactic centre, ours might be the first Solar System ‘Oumuamua has encountered since it left home, possibly billions of years ago.
Left: Blue crosshair denotes ‘Oumuamua's position in the sky as it entered the Solar system centuries ago. Centre: Trajectory of ‘Oumuamua through the inner Solar system. Right: Position of ‘Oumuamua in the sky when it leaves the Solar system centuries hence. Credits: Left and right: Sky Safari 5 Pro & J. Marchant, Centre: JPL/NASA.
Liverpool John Moores University (LJMU) is one of six institutions shortlisted for Research Project of the Year: STEM in this year's Times Higher Awards.
The nomination has been awarded for the use of the SPRAT spectrograph in the study of the unique recurrent nova M31N 2008-12a in the Andromeda Galaxy. SPRAT (SPectrograph for the Rapid Analysis of Transients) was designed and built in late 2014 by the LJMU telescope group. It uses volume phase holographic gratings to maximise efficiency and has proved to be a powerful tool for transient classification with minimal human intervention.
Novae are binary systems consisting of a white dwarf that is accreting material from its companion star. The build-up of material on the surface of the white dwarf eventually leads to a thermonuclear explosion. Some so-called recurrent novae show repeated nova eruptions, but until recently the fastest recurrence timescales were in the tens of years, with the typical timescale being much longer. M31N 2008-12a has a nova eruption every year — an unprecedented recurrence timescale. The research team at LJMU's Astrophysics Research Institute, along with their collaborators, have demonstrated this is due to the combination of a huge companion star and the most massive white dwarf ever detected in such a system, leading to an extremely rapid mass transfer rate. The high cadence spectroscopy from SPRAT has been crucial in understanding the nature of this object, and it is predicted to be the first of a whole new class of "rapid recurrent novae". Since the nova event does not completely eject the accreted material, the white dwarf continues to increase in mass, with a catastrophic Supernova Ia event being its eventual fate. The conservative upper limit on the timescale for this event is 20,000 years.
A small sample of the 70+ LT images submitted to the Gallery. © 2017 Göran Nilsson and Wim van Berlo.
The pictures were made by taking archived greyscale IO:O data that had been observed through effectively red, green and blue filters, and combining them in various ways to produce colour images. Most of the original data had been requested over the years by UK schools via the National Schools' Observatory
This skilful post-processing was performed by Swedish amateur astrophotographers Göran Nilsson and Wim van Berlo.
Göran is a professor in animal physiology at the University of Oslo, and Wim is a physics and mathematics teacher in Stockholm. Both have been interested in astronomy and astrophotography for some time; Göran even built his own observatory in the Swedish countryside in 2014.
Living so far north has its drawbacks however when it comes to astrophotography in the summer. "During a four month period, from May through August, the sun hardly sets below the horizon, and it doesn’t get dark," says Wim. Göran, situated even further north, has the same experience: "The long light summer nights make astrophotography impossible for several months," he says.
To have something astronomy-related to do during this time, the two decided to use their growing astrophotography skills to process exposures that were freely available from the Liverpool Telescope's Data Archive. Together they sifted through all available data for each of the objects they chose, stacking and combining the frames. Göran used the program Nebulosity for stacking, following up with Adobe Photoshop for final contrast enhancements that reveal hitherto unseen fine detail. Wim performed the same tasks entirely with the single package PixInsight.
The result is over seventy stunning full-colour pictures of famous and some not-so-famous astronomical objects. We are certainly delighted with the pictures, and thank Göran and Wim for allowing us to host their work on our website.
[UPDATE (26 July): The filter has now been changed. See the RISE instrument page for further details.]
The RISE fast-readout camera is having its "V+R" filter replaced with a 720 nm long-pass filter on 26th July 2017. This is being done to enhance the capabilities of the camera with regard to measurement of exoplanet transits around late-type, red dwarf stars.
More details of the filter switch can be found in the filter section of the RISE instrument page here.