Category Archives: Elliptical Galaxies

Video of the “Story of Light” in Vivid Sydney 2016

Following the success of our sold-out Event “The Story of Light – The Astronomer’s Perspective” for ViVID Sydney Ideas 2015, the Australian Astronomical Observatory (AAO) continued its collaboration with ViVID Sydney 2016 organizing “The Story of Light – Deciphering the data encoded on the cosmic light”. But actually it was me who was in charge of the organization.

The five astronomers speaking during our “Sydney Vivid Ideas: The Story of Light” started at the Powerhouse Museum, Sydney, 29th May 2016. From left to right: Luke Barnes, Alan Duffy, Vanessa Moss, Liz Mannering and Ángel López-Sánchez. Photo credit: Jenny Ghabache (AAO).

The event was held at the PowerHouse Museum in Sydney on Sunday 29th May 2016. More than 160 people attended this special event. Five young astronomers (me included) talked about Astronomy and Big Data: the light and light-based technologies developed in Australian astronomy for both optical and radio telescopes; the tools, platforms, and techniques used for data analysis and visualization; how astronomers create simulation data; how some of these techniques are being used in other research areas; and the major scientific contributions toward our understanding of the Universe. Indeed, astronomers have been pioneers in developing “Data Science” techniques to make sense of this huge data deluge, many of which are now used in other areas.

We recorded all the event in video, and it is now publicly available  in the AAO YouTube channel. Some photos of the event are also compiled below. I want to thank AAO/ITSO Research Astronomer Caroline Foster for helping recording and editing the video and Jenny Ghabache (AAO) for taking the photos of the event.

Full recording of the event “The Story of Light 2016: Deciphering the data encoded on the cosmic light” organised by the AAO for Vivid Sydney Ideas 2016. Credit: AAO. Acknowledgment: Caroline Foster (AAO).

The event was hosted by Alan Duffy (Swinburne University). I was in charge of explaining optical astronomy, the AAO, optical surveys and big data. Then my colleagues  Vanessa Moss (Univ of Sydney/CAASTRO), Luke Barnes (Univ. of Sydney) and Liz Mannering (AAO/ICRAR) discussed radio astronomy, the ASKAP and big data (Vanessa), simulating, analysing and visualizing astronomy data (Luke) and astronomy data archive, the All-Sky Virtual Observatory (ASVO) and other virtual observatories (Liz ). After the short 12-15 minutes talks (well, as usual I took a bit more time), the panel welcomed questions from the audience (and even from Twitter using #SoLSydneyIdeas) for a discussion session about Light and Astronomy and the Australian contribution to the improvement of our understanding of the Universe.

The Lecture Theatre a few minutes before our “Sydney Vivid Ideas: The Story of Light” started at the Powerhouse Museum, Sydney, 29th May 2016. Photo credit: Jenny Ghabache (AAO).

Our host, Alan Duffy, introducing the event. Photo credit: Jenny Ghabache (AAO).

AAO/MQU Research Astronomer Ángel R. López-Sánchez talking about optical astronomy, the AAO and big data. Photo credit: Jenny Ghabache (AAO).

Vanessa Moss (Univ. of Sydney/CAASTRO) talking about radioastronomy, the ASKAP and big data. Photo credit: Jenny Ghabache (AAO).

Luke Barnes (Univ. of Sydney) talking about simulating, analysing and visualizing astronomy data. Photo credit: Jenny Ghabache (AAO).

Liz Mannering (Univ. of Sydney) discussed astronomy data archive, the All-Sky Virtual Observatory (ASVO) and other virtual observatories. Photo credit: Jenny Ghabache (AAO).

Panel discussion with all participants answering questions from the audience. Photo credit: Jenny Ghabache (AAO).

Angel Lopez-Sanchez answering a question from the audience. Photo credit: Jenny Ghabache (AAO).

And last… Well, if you want to see only my talk, here it is:


New AAO video: Rainbow Fingerprints

Have you ever wondered how telescopes collect the light of the stars to be later analyzed by the astronomers? This new AAO video, entitled Rainbow Fingerprints shows how this is done at the Anglo-Australian Telescope (AAT). The video was produced by AAO Astronomer and Outreach Officer Amanda Bauer, and I have collaborated providing not only the sequences of the AAT outside and inside the dome (which were extracted from my timelapse A 2dF night at the AAT) but also providing comments during the production process.

Video “Rainbow Fingerprints” showing how the light of distant galaxies in collected by the Anglo-Australian Telescope and directed to the AAOmega spectrograph using optical fibres. More information in the AAO webpage Rainbow Fingerprints. Credit: AAO, movie produced by Amanda Bauer (AAO).

The light coming from distant galaxies is first collected using the primary mirror of the telescope, which has a diameter of 4 meters, and then it is sent using optical fibres (the 2dF system) to a dark room where the AAOmega spectrograph is located. This spectrograph, which is a series of special optics, separates the light into its rainbow spectrum, in a similar way a prism separates white light into a rainbow. The separated light is later focussed onto the CCD detector. Finally the video reveals the science quality spectra for two different types of galaxies, one spiral (top panel) and one elliptical (bottom panel), using actual data obtained with the AAT and the AAOmega spectrograph. The information codified in the rainbow fingerprint identifies each galaxy unambiguously: distance, star formation history, chemical composition, age, physical properties as the temperature or the density of the diffuse gas, and many more.

I hope you enjoy it!

Back observing at the Anglo-Australian Telescope

On 13th January 2013 the Siding Spring Observatory and the beautiful Warrumbungle National Park near Coonabarabran (NSW, Australia) were terribly affected by the worst bushfire in NSW in the last decade. Although the astronomical facilities have not experienced any severe damage, the bushfire has destroyed some houses at the Observatory (including the Lodge), burnt tens of houses and destroyed the majority of the trees in the National Park.

However, tonight Thursday 14 February, after a month and a day since the bushfire, astronomers are recommencing observing with the 3.9-m Anglo-Australian Telescope at Siding Spring Observatory. I’m one of these astronomers who are now performing the observations remotely from the Australian Astronomical Observatory (AAO) headquarters in North Ryde, Sydney, supported by technical staff at the telescope. The AAO has made public today a press release informing that astronomers are back to work at the AAT!.

The Spindle Galaxy with the AAT. It is an edge-on lenticular galaxy classified as NGC 3155 or Caldwell 53. The data were obtained on 14 February 2013 using the FPI camera of the 2dF instrument at the 3.9m Anglo-Australian Telescope located at Siding Spring Observatory. 8 x 20 s + 5 x 40 s + 1 x 60 s integration time (460 s), combined with IRAF. Colours derived using U, V and I images obtained at the 2.5m Cerro Tololo International Observatory by Kuchinski et al. (2000).
First astronomical observations after the bushfires on 13 January 2013.
Credit: Ángel R. López-Sánchez (AAO/MQ) & Lee Spitler (MQ/AAO),
Night Assistant at the AAT: Steve Chapman (AAO)

Although we are using tonight the Two Degrees Field (2dF) instrument with the AAOmega spectrograph, which allows the acquisition of up to 392 simultaneous spectra of objects anywhere within a two degree field on the sky, we have also used the auxiliary camera that 2dF possesses, the Focal Plane Imager, to take some images of the Spindle galaxy, also known NGC 3115 or Caldwell 53, a lenticular (S0) galaxy located at around 32 million light years from Earth.

However, tonight’s observations are having the AAT looking up to a billion light-years out into space to test our ideas about the still mysterious Dark Energy.