What I've been up to recently...
Theory meets Observations: Star Formation Physics Probed in Nearby Galaxies
The workshop brought together theorists and observers who work on understanding how star formation proceeds in disk galaxies by utilising high resolution simulations and observational data probing all relevant constituents (e.g. gas, dust, HII regions, star clusters).
After two years of pandemic interruptions (2020 online, 2021 no HHSF meeting), this year we had our 8th joint Heidelberg-Harvard workshop on star formation from December 6 to 9, 2022. The meeting covered the physical and chemical processes relating to star formation taking place over a broad range of scales, from extragalactic to individual star-forming regions, cores as well as protostellar disks.
Puzzles of the Galactic Centre
We hosted the "Puzzles of the Galactic Centre" meeting in Heidelberg. Our aim was to bring together experts in the study of the different aspects of the Galactic Centre (star formation, dynamics, stellar populations, energetic outflows) to identify the key puzzles pending in the field and to seek paths to solve them, both from a theoretical and observational point of view. Rather than a classical meeting format, we instead opted for every participant to lead a discussion session on an open question in their area of research. The goal was for participants to not focus on what they do understand, but instead on what they don't understand. A fascinating puzzle in their own research, why it is important, and suggestions on what is needed to solve it.
Paper day: Star formation in the Central Molecular Zone of the Milky Way
Our review of star formation at the centre of the Galaxy for Protostars & Planets VII hit the arxiv today. We have reviewed the recent observational and theoretical advances in the field, combining these to draw a comprehensive and multi-scale picture of the cycle of matter and energy in the closest galactic nucleus. We will present the paper at Protostars & Planets VII in Kyoto, Japan in the spring of 2024.
Press release: A bubble in the Brick
A group of astronomers led by the Max Planck Institute for Astronomy found evidence for a young stellar cluster hidden inside a cloud known as “the Brick”. This cloud near the Galactic Centre so far appeared unusually quiescent regarding star formation. The new finding follows from an arc-shaped substructure whose properties are consistent with an expanding shell. The authors link it to a bubble of hot gas produced by the stellar wind of a young massive star. Since massive stars rarely form in isolation, the bubble could indicate the presence of a young stellar cluster, equivalent to several hundred solar masses...read more...
ACES: The ALMA CMZ Exploration Survey
Fantastic news that our proposal "ACES" (the ALMA CMZ Exploration Survey) was accepted during cycle 8! ACES is a "Large Program" survey of the "Central Molecular Zone" (CMZ) – the inner-100 pc (300 light-years) of our Galaxy – with the ALMA telescope. ACES will derive the properties of all potentially star-forming gas in the Galactic Centre, from global (100 pc) to proto-stellar core (0.05 pc) scales, down to sub-sonic (<0.4 km/s) velocity resolution. ACES primary goal is to determine how global processes set the location, intensity and timescales for star formation and feedback in the Galactic Centre.
First in person meeting for > 1year!
This week I attended my first in-person meeting since the COVID-19 pandemic began -- an entirely discussion based meeting on the "Puzzles of Star Formation" at Ringberg Castle. I gave a discussion session on "Multi-scale gas flows in the interstellar medium and their role in the star formation process".
We made the cover of Nature Astronomy!
Our image of NGC4321 (© T. Müller/J. D. Henshaw/MPIA/PHANGS) has been used as the cover art for November's issue of Nature Astronomy. You can find the issue here.
Hats off to Thomas Müller at the Haus der Astronomie at the MPIA. Together we'd been playing around with 3D visualisation for some time and I'd mentioned that I thought it would be fun if we made it look like the Eye of Sauron. This was what he came up with :-)
Press release: The cosmic commute towards star and planet formation
The molecular gas in galaxies is organised into a hierarchy of structures. The molecular material in giant molecular gas clouds travels along intricate networks of filamentary gas lanes towards the congested centres of gas and dust where it is compressed into stars and planets, much like the millions of people commuting to cities for work around the world. To better understand this process, a team of astronomers led by Jonathan Henshaw at Max Planck Institute for Astronomy (MPIA) have measured the motion of gas flowing from galaxy scales down to the scales of the gas clumps within which individual stars form... read more...
Paper publication: Ubiquitous velocity fluctuations throughout the molecular interstellar medium"
Our Nature Astronomy publication describing the multi-scale dynamics of the interstellar medium in both the Milky Way and nearby galaxy NGC4321 (M100) has arrived! You can read the associated press release linked in the following news article.
Links to the paper:
This week I will be attending the PHANGS team meeting in Madrid, presenting recent results from our study "Ubiquitous velocity fluctuations throughout the molecular interstellar medium"
This week I will be attending "Linking the Milky Way and nearby galaxies" in Helsinki, where I will present recent results from our study "Ubiquitous velocity fluctuations throughout the molecular interstellar medium" .
Paper publication: "The Brick" is not a Brick: a comprehensive study of the structure and dynamics of the central molecular zone cloud G0.253+0.016
Our Paper describing the kinematics of G0.253+0.016 AKA 'The Brick' was published today in Monthly Notices of the Royal Astronomical Society. You can read a little bit more about it here or follow the links below for the publication itself. Along with the paper we have published two new pieces of code (see below).
Links to the paper:
ScousePy v1.0.0 is here!
As part of the Brick paper, we have developed a new Python version of SCOUSE. You can read more about the code here.
New code: acorns - Agglomerative Clustering for ORganising Nested Structures
In addition to ScousePy we have published acorns, an n-dimensional unsupervised machine-learning algorithm designed for the clustering of spectroscopic position-position-velocity data. We used acorns in the Brick paper to identify different sub-clouds within the data produced by ScousePy. You can read more about the code here.