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In brief For the first time, a team of astronomers (including IoA astronomer Nic Walton) have spotted potential signs of a rainbow-like ‘glory effect’ on a planet outside our Solar System. Glory are colourful concentric rings of light that occur only under peculiar conditions. Data from ESA’s sensitive Characterising...

If there are primordial black holes in the dark matter halo, they must collide with the Galactic neutron stars (NSs) and produce light black holes (LBHs), with masses below 1.4 M_Sun. This has observational consequences that may be checked by microlensing, by LIGO -Virgo-Kagra interferometers detecting gravitational waves from collisions of LBHs with NSs and BHs, and (possibly) by detecting LBHs in X-ray binaries and from pulsars statistics.

• Speaker: Prof. Marek Abramowicz
• Tuesday 19 March 2024, 14:00-15:00
• Venue: The Hoyle Lecture Theatre + Zoom .
• Series: Institute of Astronomy Seminars; organiser: .

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Convection is an essential process for transporting heat and moisture in planetary atmospheres. The standard Earth picture of moist convection rising from the surface is only one of a number of modes of convection. Notably, convection in atmospheres with a high condensible mass fraction (non-dilute atmospheres), or with a lighter background gas than the condensible species (e.g. water convection in a hydrogen dominated atmosphere) – acts very differently and can be much weaker or even shut down entirely in the latter case. Here I present a new mass-flux scheme which can capture these variations and simulate convection in a wide range of parameter space for use in 3D climate models. A validation using the case of Trappist-1 e is presented.

• Speaker: Edouard Barrier (University of Cambridge)
• Wednesday 13 March 2024, 13:15-13:40
• Venue: The Hoyle Lecture Theatre + Zoom .
• Series: Institute of Astronomy Seminars; organiser: Hannah Uebler.

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The CMB anisotropies are measured in several microwave frequency bands. Having this frequency information allows us to separate signals that are due to different sources. We can easily make maps that are sensitive to specific frequency combinations, and in this way isolate the contribution from the primary CMB (early-Universe) and various other CMB interactions such as the Sunyaev—Zel’dovich (SZ) effect (the scattering of the CMB from electrons in the late Universe). I will talk about constraints on the SZ effect from Planck data using a new frequency-separation code, pyilc, which we use to isolate the signal while removing other late-Universe biases, in particular the infrared emission from star-forming galaxies. I will also show an application to beyond standard model interactions between the CMB and a non-trivial dark sector, and how we can use the CMB to constrain beyond-standard-model particle physics.

• Speaker: Fiona McCarthy (DAMTP)
• Wednesday 13 March 2024, 13:40-14:05
• Venue: The Hoyle Lecture Theatre + Zoom .
• Series: Institute of Astronomy Seminars; organiser: Hannah Uebler.

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The winds that help to form planets in the gaseous discs of early solar systems have been imaged for the first time by the James Webb Space Telescope (JWST) using the noble gases neon and argon. Planetary systems like our Solar System seem to contain more rocky objects than gas-rich ones. Around our sun, these include the...

The existence of dark matter, which constitutes 85% of the matter density and 26% of the total energy density, is clearly demonstrated by cosmological observations of the Universe. And yet, very little is known about the nature of dark matter. The observations support the ‘cold dark matter’ (CDM) paradigm, in which the dark matter is a heavy particle, with little to no interactions through fundamental forces other than gravity. The cosmological and astrophysical observations of dark matter’s gravitational interaction currently provide the only robust evidence of dark matter. These observations typically rely on characterising the distribution of matter in the Universe. A dark matter particle that is lighter than the standard CDM paradigm predicts imprints a suppression of structure in the matter distribution. The exact scale where this happens is most often linked to the mass of the dark matter particle. I will present new results on the thermal relic warm dark matter constraints using the high-redshift cosmic web as traced by the Lyman-alpha forest.

• Speaker: Vid Iršič
• Wednesday 06 March 2024, 13:15-13:40
• Venue: The Hoyle Lecture Theatre + Zoom .
• Series: Institute of Astronomy Seminars; organiser: .

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The origin of life is an event so rare that, to the best of our knowledge, it has only happened once: here on Earth. The questions of how life developed and in what environments geochemical reactions took place are fundamental questions that span the fields of astrobiology, organic chemistry, and geology. One key...

cdm_2_copy.jpg In their latest research on dark matter scientists have collected vital clues about the ‘coldness’ of the mysterious component making up 80% of all matter, revealing a deep connection between dark matter and the formation of galaxies in the early Universe. With the help of powerful telescopes, the...

The Crafoord Prize in Astronomy The Crafoord Prize in Astronomy 2024 is awarded to Douglas Gough , University of Cambridge, UK, Jørgen Christensen-Dalsgaard , Aarhus University, Denmark, and Conny Aerts , KU Leuven, Belgium “for developing the methods of asteroseismology and their application to the study of the interior...

germl2rwwaa-rym.jpeg Following today´s Adoption, the LISA mission advances to the construction phase LISA, the Laser Interferometer Space Antenna, has passed a major review with flying colours: the entire concept - from the definition of the overall mission and operations to the space hardware to be built - stood up to the...

hp_dec_23_art.jpeg Physics breakthroughs don’t always require city-sized particle colliders or giant radio telescope arrays. The Gordon and Betty Moore Foundation , the Simons Foundation , the Alfred P. Sloan Foundation and the John Templeton Foundation have partnered to fund 11 innovative “tabletop” experiments, many of...

weic2402a-2.jpg One of the key missions of the NASA/ESA/CSA James Webb Space Telescope is to probe the early Universe. Now, the unmatched resolution and sensitivity of Webb’s NIRCam instrument have revealed, for the first time, what lies in the local environment of galaxies in the very early Universe. This has solved one...

How did the molecular building blocks for life end up on Earth? One long-standing theory is that they could have been delivered by comets. Now, researchers from the IoA have shown how comets could deposit similar building blocks to other planets in the galaxy. In order to deliver organic material, comets need to be...