Tag Archives: 2013

Feeding, Feedback and Fireworks in galaxies

During this week (23 – 28 June 2013), I’m participating in the international astrophysics conference “Feeding, Feedback, and Fireworks: Celebrating Our Cosmic Landscape”, which is hosted in the tropical paradise of Hamilton Island, one of the most important islands of the Whitsundays (Queensland, Australia). The conference is jointly supported by the Australian Astronomical Observatory (AAO) and the CSIRO Astronomy and Space Science (CASS) and it is the 6th of the Southern Cross Conference Series.

Poster of the “Feeding, Feedback, and Fireworks: Celebrating Our Cosmic Landscape”, jointly supported by the Australian Astronomical Observatory (AAO) and the CSIRO Astronomy and Space Science (CASS), being the 6th of the Southern Cross Conference Series. The Heart Reef near Hamilton Island appears in the foreground, while the Hubble Ultra-Deep Field image is the background image.
Credit: Heart Reef Photo and Fireworks: Ángel R. López-Sánchez (Australian Astronomical Observatory / Macquarie University); Hubble Ultra-Deep Field: NASA, ESA and R. Thompson (Univ. Arizona).

It has been a very intense and fruitful conference, with almost 100 participants (the majority coming from Australia, but many others from America, Europe, Asia and Africa), and we are discussing hot topics about how the diffuse gas is moved inside the galaxies (Feeding), how stars form in galaxies (Fireworks) and how these newborn stars alter the properties of their host galaxies and their surroundings (Feedback). We are also investigating the role of the Active Galactic Nuclei (AGN) in galaxy evolution: how are they triggered (Feeding) and how they affect their host galaxies and even the galaxy cluster their host galaxies reside (Feedback). All in the context of the cosmological evolution of the Universe, constraining theoretical models using observations, and trying to put all the pieces together to understand the evolution of the galaxies.

In my case I presented part of my multi-wavelength work in Blue Compact Dwarf Galaxies, which are small galaxies (smaller than 1/100 times the size and mass of the Milky Way) which are experiencing a very intense star-formation event. Hence, it seems all the dwarf galaxy is a giant nebula! I’ll describe these interesting objects in a future post.

I’m part of the “LOC”, the Local Organizing Committee, which is chaired by Amanda Bauer (AAO), aka @astropixie, and hence in the last months I have actively participate to get the conference smoothly running (conference booklet, schedule of the talks, helping in registration and photos). One of my tasks during this week was to get the “Conference Photo” which, as Amanda suggested, includes not only the beach and palm trees of the beautiful beach at Hamilton Island but also a nice night-sky photo showing the Southern Cross. The result is this:

Conference Photo of the “Feeding, Feedback, and Fireworks: Celebrating Our Cosmic Landscape” conference.
Photo Credit and composition: Ángel R. López-Sánchez (Australian Astronomical Observatory / Macquarie University).

The talks and more information about this exciting conference will be posted in the conference webpage soon.

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Partial solar eclipse from Sydney

Today, 10th May 2013, the combined movements of the Sun, Earth and Moon gave us a very nice Annular Solar Eclipse. Following a similar path to the Total Solar Eclipse we enjoyed last November, the shadow of the Moon over the Earth moved from North Australia to the Pacific. However, today the Moon was close to its maximum distance to the Earth (planets and satellites move following elliptical orbits) and hence its apparent size on the sky was not big enough to completely cover the disc of the Sun. This is indeed the reason the eclipse was an annular solar eclipse.

In this occasion I couldn’t travel to North Australia to enjoy the annular eclipse (actually, I have seen 2 of these in the past, the most recent one was on 3rd October 2005 from Madrid), and even last night I didn’t expect to do anything special about this today. But this morning, while watching it from my backyard using my solar glasses, I decided just to take some few shots using not the telescope but only the tele lens. This is the result:

Partial Solar Eclipse from Sydney. Data obtained using a CANON EOS 600D, a 250mm Tele Lens and a Solar filter (which I hold by hand). I stacked 12 individual frames obtained at ISO 100, f10, 1/80 s using the Lynkeos software. The final processing was achieved using Photoshop. 10 May 2013 @ 09: 10 AEST ( 00:10 UT ), Sydney, Australia.
Credit: Ángel R. López-Sánchez (Australian Astronomical Observatory / Macquarie University, Agrupación Astronómica de Córdoba / Red Andaluza de Astronomía)

I hope you like it.

Stories from Siding Spring Observatory

Tonight we’re opening the photo exhibition Stories from Siding Spring Observatory at Sydney Observatory.

Baner of the Photo Exhibition Stories from Siding Spring Observatory opening tonight at Sydney Observatory. The Exhibition will be opened to the public between 18 April 2013 and 13 August 2013. As the general visit to Sydney Observatory, it is free.
Credit: Á.R.L-S.

This photo exhibition compiles 25 photos plus four time-lapse videos taken at the Siding Spring Observatory by staff of the Australian Astronomical Observatory. I have actively participated in the organization of this photo exhibition, not only providing some photos (see below) but also the 4 time-lapse videos, one of them specifically prepared for this.

The idea of organizing the photo exhibition came after the terrible bushfires that destroyed the Warrumbungle National Park and seriously affected Siding Spring Observatory on 13th January 2013. Luckily any telescope experienced any damage and we were back at the telescopes just 1 month after the bushfires. However, some houses and facilities, including the ANU Lodge, were destroyed in the bushfires. The vegetation at the site was also seriously affected, and indeed the views from there are not now as beautiful as they were before.

As the brochure of the Exhibition quotes,

Siding Spring Observatory sits on a mountaintop in the Warrumbungle Range, 400 km northwest of Sydney and 25 km west of the town of Coonabarabran. Run by the Australian National University, it is Australia’s most important site for optical astronomy.

On 13 January 2013 a bushfire swept through the observatory. Despite damage to some buildings, the telescopes were unharmed and are now back at work.

The photos in this exhibition tell stories of life and work on the mountain. They were taken by staff of the Australian Astronomical Observatory (AAO), which operates two telescopes there: the 4-m Anglo-Australian Telescope (AAT) and the UK Schmidt telescope.

Yesterday evening some of us were there installing the Exhibition and hanging frames and labels from the walls of the Sydney Observatory:

Working hard to get all frames and labels done on time!
Credit: Á.R.L-S.

Jamie Gilbert (AAO) carefully hanging label to my photo “Day and Night”.
Credit: Á.R.L-S.

The photos I’m providing for the Exhibition are these:

The 3.9m Anglo-Australian Telescope (AAT).
Credit: Á.R.L-S.

The 2dF instrument attached to the primary focus of the AAT.
Note that the mirror of the telescope is opened.
Credit: Á.R.L-S.

Day and Night at the AAT.
Credit: Á.R.L-S.

Circumpolar stars over the AAT on a dark winter night.
Credit: Á.R.L-S.

Double Rainbow at the sunrise over the Warrumbungle National Park. Photos taken from the catwalk of the AAT by Amanda Bauer (AAO) and processed and stitched by me.
Credit: Amanda Bauer & Ángel R. López-Sánchez.

but you can find many more photos I took at Siding Spring Observatory during the last years in this album of my Flickr.

However I have to confess that, as Amanda Bauer says in her blog, the best of the photos we have chosen is this spectacular panorama of the Milky Way over the AAT obtained by Jamie Gilbert (AAO):

Panorama of the Milky Way over the Anglo-Australian Telescope (AAT) using a CANON 5D Mark III. More information about this image: here.
Credit: Jamie Gilbert (AAO)

and that is why this photo is the largest one!

Jamie Gilbert and the frame with his panorama “The Milky Way over the AAT” during the installation of the photos of the “Stories from Siding Spring Observatory” Exhibition at Sydney Observatory on the evening of 16 April 2013
Credit: Á.R.L-S.

The Photo Exhibition Stories from Siding Spring Observatory is open to the public between 18 April 2013 and 13 August 2013. As the general visit to Sydney Observatory, it is free, so do not miss it if you have a chance!

Earth Hour 2013 in Sydney

Last 23rd March 2013 I was invited to give a Public Talk at Sydney Observatory because of the Earth Hour 2013. More than 200 people attended this event, I have to say I think it was not because of me but because of the possibility of getting a somewhat darker sky than usual in the city center. Earth Hour is a worldwide event organized by the World Wide Fund for Nature (WWF) that encourages households and businesses to turn off their non-essential lights for one hour. The aim of this is to raise awareness about the need to take action on climate change and, in particular, the problem of the light pollution. The Earth Hour first took place in 31st March 2007 in Sydney, which has a participation of 2.2 million Sydneysiders. In 2008 many other cities around the world adopted the event, creating a movement in which now participates around 1 billion people in more than 150 countries.

What is light pollution? It can be defined as the excessive or inappropriate outdoor lighting. Common forms of light pollution include glare, sky glow, light trespass, and light clutter. As the International Dark Sky Association (IDA) specifies in its main brouchure

Urban dwellers everywhere are losing the ability to see planets and stars in the night sky. The spectacular view of the Cosmos that has inspired science and art throughout history is disappearing. The glow of uncontrolled outdoor lighting has hidden the stars and changed our perception of the night. Light pollution wastes energy ( = MONEY! ), harms ecosystems, increases greenhouse gasses, threatens astronomical research and affect human health. Better lightning is the solution! The problems from light pollution can be solved by utilizing efficient, modestly bright outdoor lighting fixtures that are directed toward the ground and shielded to control glare.

Empire State Building in New York city at night. The light pollution is a terrible problem in large cities, giving the sky that orange colour. Sadly, today many children think that this is the real color of the night sky. Picture taken in October 2004.
Credit: Charliebrown7034 (Wikipedia).

Beside the negative effect that the light pollution has in the environment and its effects in animals and persons, I want to emphasize that its main consequence (at least, that which sadly is more important) is the huge amount of money which is wasted to illuminate the clouds and hide the stars. People around the world are realizing that this stupid kind of pollution has an easy solution. However it is responsibility of we, scientists, to talk about this to the general public and also to our Governments. Following the document Public Lighting—Energy Efficient Street Lighting published in July 2008 by the Australian Government,

In Australia, public lighting is the single largest source of local government’s greenhouse gas emissions, typically accounting for 30 to 50% of their CO2 emissions. There are 1.94 million public lights — one for every 10 Australians — that annually cost A$210 million, use 1,035 GWh of electricity and are responsible for 1.15 million tonnes of CO2 emissions.

Photos comparing the vision of the Sydney Harbour Bridge and the Sydney Opera House during the Earth Hour on 28th March 2003 (top row) and after that event (bottom row). All 4 images were taken from the same place using a camera CANON EOS 400D, 400 ISO, f10 and 20 seconds exposure. The decreasing of the light pollution (seen specially well in the clouds) is quite evident.
Credit: Á.R.L-S. (AAO/MQ)


I emphasized, however, that the light pollution in Australia is (still) not bad at all. Australia has some of the darkest places on Earth (I was really impressed about how stars shine from the Australian Desert), are indeed Sydney, which has 4.5 million people, has by far better night skies that those seen from the city I’m from, Córdoba (Spain), with only 350 thousand people. As an example, just check this image I took in 2011 New Year Eve from the Opera Bar, just downstairs of the Sydney Opera House

Vision of the Sydney Opera House from the Opera Bar on the 2011 New Year Eve. It is just a 10 seconds exposure at f6.3 and 400 ISO using a CANON EOS 400D camera. The main stars of the Orion and Taurus (The Bull) constellations are clearly seen, as well as the Pleiades and even the Orion Nebula as a diffuse dot!
Credit: Á.R.L-S. (AAO/MQ)

After discussing the light pollution, its effects and some projects aimed to reduce it, I used the second half of my time to talk about my research at the Australian Astronomical Observatory / Macquarie University. I explained what an astronomer usually does, where the Siding Spring Observatory is, and presented some results of my own research about star-formation in galaxies.

A moment during my Public Talk at Sydney Observatory on 23rd March 2013 just before the Earth Hour. I was explaining here the problem of the light pollution, although later I talked about my research and work at the Australian Astronomical Observatory and Macquarie University.
Credit: Jeanette Landstedt (Sydney Observatory).

After the talk the participants enjoyed some stargazing using the amateur telescopes provided by the Sydney Observatory. I was among them and couldn’t stop talking to one and another group, as I was still being asked about what I said during my talk. It was great to be able to do this in the very relaxing atmosphere of an amateur observation. The only bad thing was that there was still a lot of light coming from the Moon, indeed, choosing the weekend before Easter for the Earth Hour was not good as it was not possible to really check the actual difference induced by the deficit of illumination in the sky.

Public Talk at UNSW: “Surprises of the Cosmos”

Next Friday 8th March 2013, at 6:30 pm, I’m giving a Public Lecture at the School of Physics of the University of New South Wales (UNSW), Sydney. I’m presenting an updated version of my nice talk Surprises of the Cosmos which I prepared in 2009 because of the Photo Exhibition co-organized between the Instituto Cervantes (Spain) and the Canary Islands Astrophysical Institute (IAC, Instituto de Astrofísica de Canarias, Spain) in 2009 because of the International Year of Astronomy. I participated in this exhibition and later I have given same talks here in Australia (Sydney, Melbourne and Canberra) publicizing it.


Flyer of the Public Talk “Surprises of the Cosmos” which I will give next Friday 8th March 2013 at the School of Physics of the University of New South Wales (UNSW), Sydney Credit: UNSW / Angel R. López-Sánchez.

In this talk I imagine we are far, far away from the Earth and take a journey from the deep Universe to our home planet. Our travel will start far away from the Earth, in galaxy clusters containing tens of thousands of galaxies and located more than 10 billion light years from us. We will see how galaxies formed and how we think our Milky Way and it’s neighbours have evolved in time. Once in our Galaxy we will have a look to some remarkable objects: star-forming regions, star clusters and nebulae that are the remnants of dead stars. Finally, we will reach the Solar System and have a look to the planets and the dwarf planets that orbit the Sun. We will also visit comets and asteroids, explain their origin and emphasis how the study of such bodies allow scientist to get a better understanding in the formation of the Sun and the planets around 4.7 billion years ago. We will finish the journey in our planet visiting some of the most important astronomical observatories of the Earth.

The details of the talk and how to reach the Lecture Theater are included in these dedicated UNSW webpage and in the UNSW Events in Facebook

Where: Physics Lecture Theatre, Old Main Building, UNSW Kensington Campus (near Gate 14, Barker St), Sydney

Date: Friday March 8th 2013

Time: 6:30pm (Refreshments served from 6pm)

You can see all the images of this exhibition with the text in Spanish in this link.

Finally, I want to thank PhD student Vicki Lowe for inviting me to give this talk.

I’ll see you there!

Moon, Jupiter, Jewel Box and Comet Lemmon

Besides being an astrophysicist I’m an active amateur astronomer. After 6 years living in Australia, finally in May 2012 I bought my own, small amateur telescope: Skywatcher Black Diamond Refractor Telescope, with an aperture of 80 mm and a focal distance of 600 mm. It provides beautiful images of the sky. However, besides once while stayed at Siding Spring Observatory and the two “great astronomical events” of 2012 (and the final reason I got the telescope), the Transit of Venus in June and the Total Solar Eclipse in November, I have not had too much time to play with this toy.

Last Monday 18th February it was clear in Sydney and I tried to get some shots of the conjunction between the Moon and Jupiter (actually, from South Australia the Moon occulted Jupiter!). This is the vision I got from my telescope:


Conjunction between the Moon and Jupiter observed from Sydney on 18th February 2013. I used my Skywatcher Black Diamond Telescope D = 80 mm, f = 600 mm and my CANON EOS 600D at primary focus, at 200 ISO. It is a composition of two images: one taken at speed 1/60 and another at 1/10. I did what I could to get a nice balance between them. Credit: Angel R. López-Sánchez.

After this, I decided to try to find the bright comet Lemmon 2012 F6, that was located near the Small Magellanic Cloud. It was actually easier I thought and, besides the light pollution, I got it. So on Tuesday 19th, again clear, I prepared the telescope but this time including the motors and performing an alignment of the mount to the South Celestial Pole. This task is not easy when there is too much light in the sky, as the stars used to do it are faint. At the end I got this view of the comet. I was not able to detect the tail with my eyes, however it does appear when combining several frames, as I did for this image.

My vision of the comet Lemmon 2012 F6 from Sydney on Tuesday 19th February 2012, at 21:20 AEST (10:20 UT). I combined 7 frames of 6 seconds exposure each (42 seconds total exposition time), at 1600 ISO using Skywatcher Black Diamond Telescope D = 80 mm, f = 600 mm and my CANON EOS 600D at primary focus. Note the faint tail moving towards the upper-left. Credit: Angel R. López-Sánchez.


An annotated version of this image can be found here:


Annotated version of my vision of the comet Lemmon 2012 F6 from Sydney on Tuesday 19th February 2012, at 21:20 AEST (10:20 UT). I combined 7 frames of 6 seconds exposure each (42 seconds total exposition time), at 1600 ISO using Skywatcher Black Diamond Telescope D = 80 mm, f = 600 mm and my CANON EOS 600D at primary focus. I have included an arrow folowing the faint tail, the orientation, and the position of the star &epsilon Tucanae. Credit: Angel R. López-Sánchez.

To get a good focus I decided to use the famous Jewel Box star cluster, very close to Mimosa (β Crucis).


Image of the “Jewel Box” star cluster (NGC 4755 or Kappa Crucis) in the Southern Cross from Sydney (actually, 4 km from the city center) on Tuesday 19th February 2013, 20:50 AEST (09:50 UT). It combines 6 images with 5 seconds exposure each ( 30 seconds total time) at 400 ISO, using a Skywatcher Black Diamond Telescope D = 80 mm, f = 600 mm and my CANON EOS 600D at primary focus. The bright star at the left is Mimosa, β Crucis, one of the brightest stars of the Southern Cross. Credit: Angel R. López-Sánchez.


Any of these images are very spectacular but considering that they have been taken just 4 km from the center of Sydney, with all the light pollution, plus the extra “fight” with the mozzies, I’m happy to share them with you.