Phil Armitage
@philip-armitage.bsky.social
Astrophysicist at Flatiron CCA & Stony Brook working on accretion and planet formation. Also Mr. Pisconti / Nico’s dad / hiker / Zwifter / (lapsed) photographer
New paper, led by Jake Hassan, on the structure and evolution of quasi-stars: accreting black holes embedded in massive envelopes. This is a model for the growth of black hole seeds, and, maybe 🤞, for JWSTs “Little Red Dots”. Time will tell…
arxiv.org/abs/2510.18301
arxiv.org/abs/2510.18301
October 22, 2025 at 4:52 PM
New paper, led by Jake Hassan, on the structure and evolution of quasi-stars: accreting black holes embedded in massive envelopes. This is a model for the growth of black hole seeds, and, maybe 🤞, for JWSTs “Little Red Dots”. Time will tell…
arxiv.org/abs/2510.18301
arxiv.org/abs/2510.18301
Reposted by Phil Armitage
Polka-dotted Stars II: Starspots and obliquities of Kepler-17 and Kepler-63. Sabina Sagynbayeva et. al. https://arxiv.org/abs/2510.07130
October 9, 2025 at 4:25 AM
Polka-dotted Stars II: Starspots and obliquities of Kepler-17 and Kepler-63. Sabina Sagynbayeva et. al. https://arxiv.org/abs/2510.07130
With Navin Tsung and collaborators, we show how magnetic fields can effectively suppress gravitational instability and fragmentation in AGN accretion disks.
arxiv.org/abs/2507.21991
arxiv.org/abs/2507.21991
Does magnetic field promote or suppress fragmentation in AGN disks? Results from local shearing box simulations with simple cooling
Accretion disks in Active Galactic Nuclei (AGN) are predicted to become gravitationally unstable substantially interior to the black hole's sphere of influence, at radii where the disk is simultaneous...
arxiv.org
July 30, 2025 at 8:48 PM
With Navin Tsung and collaborators, we show how magnetic fields can effectively suppress gravitational instability and fragmentation in AGN accretion disks.
arxiv.org/abs/2507.21991
arxiv.org/abs/2507.21991
Reposted by Phil Armitage
A timely paper for #HWO25: is it enough to find Earth-like planets around other nearby stars? No! We need their planetary system contexts. Does life on Earth depend on Jupiter?
@sabinastro.bsky.social led this nice analysis of HWO requirements to detect Earths + Jupiters.
arxiv.org/abs/2507.21443
@sabinastro.bsky.social led this nice analysis of HWO requirements to detect Earths + Jupiters.
arxiv.org/abs/2507.21443
Requirements for Joint Orbital Characterization of Cold Giants and Habitable Worlds with Habitable Worlds Observatory
We determine optimal requirements for the joint detection of habitable-zone planets and cold giant planets with the Habitable Worlds Observatory (HWO). Analysis of 164 nearby stars shows that a corona...
arxiv.org
July 30, 2025 at 6:26 PM
A timely paper for #HWO25: is it enough to find Earth-like planets around other nearby stars? No! We need their planetary system contexts. Does life on Earth depend on Jupiter?
@sabinastro.bsky.social led this nice analysis of HWO requirements to detect Earths + Jupiters.
arxiv.org/abs/2507.21443
@sabinastro.bsky.social led this nice analysis of HWO requirements to detect Earths + Jupiters.
arxiv.org/abs/2507.21443
Reposted by Phil Armitage
Me and hubby discussing the new LIGO discovery of ginormous merging black holes.
Me to 3 yo: Nico, do you like black holes?
3 yo: No, I like YouTube.
Hubby: well, that's kinda a hybrid black/white hole: light comes out but no information 🤣
Happy #NerdyTuesday! 🧪
@philip-armitage.bsky.social
Me to 3 yo: Nico, do you like black holes?
3 yo: No, I like YouTube.
Hubby: well, that's kinda a hybrid black/white hole: light comes out but no information 🤣
Happy #NerdyTuesday! 🧪
@philip-armitage.bsky.social
Monster black hole merger is biggest ever seen
Gravitational wave detector LIGO spots fast-spinning ‘forbidden’ black holes that challenge physics models.
www.nature.com
July 15, 2025 at 3:58 PM
Me and hubby discussing the new LIGO discovery of ginormous merging black holes.
Me to 3 yo: Nico, do you like black holes?
3 yo: No, I like YouTube.
Hubby: well, that's kinda a hybrid black/white hole: light comes out but no information 🤣
Happy #NerdyTuesday! 🧪
@philip-armitage.bsky.social
Me to 3 yo: Nico, do you like black holes?
3 yo: No, I like YouTube.
Hubby: well, that's kinda a hybrid black/white hole: light comes out but no information 🤣
Happy #NerdyTuesday! 🧪
@philip-armitage.bsky.social
In work led by Alessandro Ruzza, we use a new simulation-based inference approach to estimate masses of disk embedded planets from ALMA data.
arxiv.org/abs/2506.11200
arxiv.org/abs/2506.11200
DBNets2.0: simulation-based inference for planet-induced dust substructures in protoplanetary discs
Dust substructures in protoplanetary discs can be signatures of embedded young planets whose detection and characterisation would provide a better understanding of planet formation. Traditional techni...
arxiv.org
June 16, 2025 at 1:03 PM
In work led by Alessandro Ruzza, we use a new simulation-based inference approach to estimate masses of disk embedded planets from ALMA data.
arxiv.org/abs/2506.11200
arxiv.org/abs/2506.11200
From today’s ethics training I learned that the threshold for a nominal gift in New York State is $15. The temptation to ask about jumbo jets was strong…
May 27, 2025 at 7:48 PM
From today’s ethics training I learned that the threshold for a nominal gift in New York State is $15. The temptation to ask about jumbo jets was strong…
Thread on our simulation work on circumplanetary disks, led by @sabinastro.bsky.social with Alexandra Kuznetsova and Yan-Fei Jiang from @flatironinstitute.org. We’re working to understand when such disks form, and what their structure looks like as we zoom in closer to the planet.
Okay, I am giving a talk on the paper tomorrow, so here’s the thread on my CPDs paper with my slides! arxiv.org/pdf/2410.14896
arxiv.org
May 23, 2025 at 12:28 PM
Thread on our simulation work on circumplanetary disks, led by @sabinastro.bsky.social with Alexandra Kuznetsova and Yan-Fei Jiang from @flatironinstitute.org. We’re working to understand when such disks form, and what their structure looks like as we zoom in closer to the planet.
Reposted by Phil Armitage
😂🤣
May 18, 2025 at 12:55 AM
😂🤣
Reposted by Phil Armitage
If you too are experiencing mental health issues due to the ongoing shitshow, please DM me or Signal me at ziadadina.19, I am trying to build a community to help each other.
Y'all, please repost and help me out, this is serious stuff
Y'all, please repost and help me out, this is serious stuff
April 24, 2025 at 2:33 PM
If you too are experiencing mental health issues due to the ongoing shitshow, please DM me or Signal me at ziadadina.19, I am trying to build a community to help each other.
Y'all, please repost and help me out, this is serious stuff
Y'all, please repost and help me out, this is serious stuff
Reposted by Phil Armitage
New paper, led by the amazing @becastro.bsky.social (with Jeremy Smallwood, Andrew Winter, @astrohoss.bsky.social, and others). In which we try to understand the formation of the crazy-looking young planetary system IRAS04125... 🤔 🔭
arxiv.org/abs/2504.07182
arxiv.org/abs/2504.07182
Disc-planet misalignment from an unstable triple system: IRAS04125
The IRAS01425+2902 wide binary system was recently reported to have both a young planet and a puzzling geometric arrangement, where the planet and binary both orbit edge-on, but misaligned by 60 deg t...
arxiv.org
April 11, 2025 at 7:40 AM
New paper, led by the amazing @becastro.bsky.social (with Jeremy Smallwood, Andrew Winter, @astrohoss.bsky.social, and others). In which we try to understand the formation of the crazy-looking young planetary system IRAS04125... 🤔 🔭
arxiv.org/abs/2504.07182
arxiv.org/abs/2504.07182
Daniel Carrera, Linn Eriksson and collaborators study a “hybrid” mode of planetesimal formation, in which the growth of dust in vortices ultimately drives the system into the collapse regime of streaming instability parameter space.
arxiv.org/abs/2504.06332
arxiv.org/abs/2504.06332
Positive Feedback II: How Dust Coagulation inside Vortices Can Form Planetesimals at Low Metallicity
The origin of planetesimals ($\sim$100 km planet building blocks) has confounded astronomers for decades, as numerous growth barriers appear to impede their formation. In a recent paper we proposed a ...
arxiv.org
April 11, 2025 at 12:12 PM
Daniel Carrera, Linn Eriksson and collaborators study a “hybrid” mode of planetesimal formation, in which the growth of dust in vortices ultimately drives the system into the collapse regime of streaming instability parameter space.
arxiv.org/abs/2504.06332
arxiv.org/abs/2504.06332