maravelias.info

about Grigoris Maravelias

maravelias.info

maravelias.info

maravelias.info

about Grigoris Maravelias

the basics

who am i?

Astrophysicist with a robust foundation in Physics and Engineering, complemented by proficient Data Science skills encompassing statistics and machine/deep learning applications.

current position

Since September 2018 I am working as a post-doc at the National Observatory of Athens (although you will finding me more in Heraklion, Crete), with Dr. Alceste Bonanos for the ASSESS project.

research interests

Observational Astrophysics focusing on stellar astrophysics and massive stars (phases, evolution), in different galaxies. Use of statistical tools and implementation of machine/deep learning approaches. Professional-amateur networking and collaborations, and Openness in Astronomy.

Latest publications

blog

The 2024 Summer School for Astrostatistics in Crete – the announcement

The deadline for the 2024 iteration of the Summer School for Astrostatistics in Crete is approaching fast. We are excited to host this event, which actually starts to settle as an annual event. And why not since it seems there is a huge need in practical training in statistics and …

New paper: X-Shooting ULLYSES: Massive Stars at low metallicity: II. DR1: Advanced optical data products for the Magellanic Clouds

Paper II of the XShootU collaboration is finally accepted at A&A! That is a cornerstone paper for the collaboration since it presents the analysis of the observations and provides the final scientific products with which the whole collaboration (and everybody else) can work with. X-Shooting ULLYSES: Massive Stars at low …

New paper: Investigating episodic mass loss in evolved massive stars: I. Spectroscopy of dusty massive stars in ten southern galaxies

A paper that collectively presents the results from our intensive observing campaign in the ASSESS project, focusing on the southern galaxies (a forthcoming paper will deal with the northern ones). Investigating episodic mass loss in evolved massive stars: I. Spectroscopy of dusty massive stars in ten southern galaxies A.Z. Bonanos, …

How does the distance affects the stars we see?

With increasing distance fainter stars, and therefore those of lower luminosity, older populations, become less observable. This means that with increasing distance we actually probe different parts of a Color-Magnitude diagram (CMD), which mainly consists of the brightest and more evolved massive stars. This is best shown in this figure …

New paper: Introducing the ASSESS project: Episodic Mass Loss in Evolved Massive Stars – Key to Understanding the Explosive Early Universe

This is the paper that describes the ASSESS project for which I have been working since 2018 ! Introducing the ASSESS project: Episodic Mass Loss in Evolved Massive Stars – Key to Understanding the Explosive Early Universe A.Z. Bonanos, G. Maravelias, M. Yang, F. Tramper, S. de Wit, E. Zapartas, …

Contributions to the 16th Hellenic Astronomical Conference

Between 26-28 of July (2023), I managed to participate in-person the 16th Hellenic Astronomical Conference, held in Athens. I personally contributed with one talk and one poster (long gone the days that I would submit two talks!), which was part of the ASSESS group’s contribution with another two talks, and …

New paper: Discovering New B[e] Supergiants and Candidate Luminous Blue Variables in Nearby Galaxies

Although I thought at the beginning that this would be a quick paper, it took considerable time to complete! Thanks a lot to Stephan that did significant work with figures I was able to focus on the text and the discussion. This is the first work to reveal B[e] Supergiants …

New paper: X-Shooting ULLYSES: massive stars at low metallicity I. Project Description

It was back in 2020 during the pandemic that the first call for the XShootU collaboration was sent. I had really little idea of what would follow, but I fount it definitely motivating to participate. Therefore I volunteer to help with the data reduction. After 2.5 years we are getting …

New Paper: Evolved Massive Stars at Low-metallicity V. Mass-Loss Rate of Red Supergiant Stars in the Small Magellanic Cloud

Evolved Massive Stars at Low-metallicity V. Mass-Loss Rate of Red Supergiant Stars in the Small Magellanic Cloud Ming Yang (杨明), Alceste Z. Bonanos, Biwei Jiang (姜碧沩), Emmanouil Zapartas, Jian Gao (高健), Yi Ren(任逸), Man I Lam (林敏仪), Tianding Wang (王天丁), Grigoris Maravelias, Panagiotis Gavras, Shu Wang (王舒), Xiaodian Chen (陈孝钿), …