Archive for 2017

The first neutron star merger

By grigoris | Filed in Astronomy

A new era, of multi-messenger astronomy (combining gravitational waves, particles, photons), has been born today. LIGO/VIRGO plus 70 teams around the world announced the first detection of colliding neutron stars, which means that a gravitational wave detection (GW170817) triggered the observations using almost everything available (from gamma rays to radio wavelengths) that identify and follow […]

The last day at Valparaiso

By grigoris | Filed in Astronomy

I think it had everything: – waking up early to go to the bank, – then go to the university and finalize some aspects of my talk (as a final contribution), – go for lunch with the whole group, – return to the university, – to say goodbye to people, – do the presentation, – […]

Every Monday the IFA-UV organizes a meeting that starts with a short (or longer) presentation of 20 mins. The whole process requires the active participation by the students to present the speaker, control, the discussion, while there is also a feedback given by the audience to the speaker. This is a great opportunity for the […]

The idea of this post came to me on my second or third day in Chile when I noticed its flag on some boats. As today is my last day at work, perhaps it is the best (and last) opportunity to make a post about it. (So, practically it is either now or never.) My […]


Proper acknowledgments

By grigoris | Filed in Astronomy

From a friend with a similar interest in martial arts. He noticed the following acknowledgment (by Zeng & Sasselov 2013, PASP, 125, 227): We acknowledge partial support for this work by NASA cooperative agreement NNX09AJ50A (Kepler Mission science team). We would like to thank Michail Petaev and Stein Jacobsen for their valuable comments and suggestions. […]

Resolving the circumstellar environment of the Galactic B[e] supergiant star MWC 137 from large to small scales Michaela Kraus, Tiina Liimets, Cristina E. Cappa, Lydia S. Cidale, Dieter H. Nickeler, Nicolas U. Duronea, Maria L. Arias, Diah S. Gunawan, Mary E. Oksala, Marcelo Borges Fernandes, Grigoris Maravelias, Michel Cure, Miguel Santander-Garcia The Galactic object MWC […]

Tough days the last days

By grigoris | Filed in Astronomy

A couple of hectic weeks finished on last Friday. After two trips to La Serena to observe from the magnificent facilities at CTIO and LCO (posts still pending since there is an overwhelming amount of photos and videos!), I had an intense week to finalize the paper I am preparing (for some looong time now). […]

Linking classical to dwarf novae

By grigoris | Filed in Astronomy

In a recent Nature (Shara et al. 2017, Nature, 548, 558) letter, the authors found that a current dwarf nova is actually the Nova Scorpii AD 1437, recorded by Korean astronomers at that time. What is interesting is that they managed to trace both the dwarf nova’s position and the center of the observed gas […]

An IFA-UV seminar talk

By grigoris | Filed in Astronomy

Yesterday, I had finally the opportunity to give a seminar talk at the Instituto de Física y Astronomía de la Universidad de Valparaíso, where I am currently based (and only for about a month more …) “What have we learned from observations of B[e] Supergiants ?” Abstract: B[e] Supergiants are a rare phase among the […]

Only on the second day of my arrival in Chile (Jan 13, 2017) I found myself traveling from Valparaiso to Santiago to go to the Universidad Catolica Observatory (long title: Pontificia Universidad Católica de Chile), for spectroscopic observations (of bright Be stars). It is located about 50-60km from Santiago at an altitude of 1450m (and […]