g-ASTRONOMY: The Universe, on the Tip of your Tongue

Posted on Mar 15, 2017 in g-ASTRONOMY, Hands-On Universe, Outreach, Public lecture

An exciting and innovative public engagement project, g-ASTRONOMY, will bring the wonders of the universe to people with sight loss through a multi-sensorial gastronomical experience on March 14th 2017. g-ASTRONOMY aims to break the assumption that astronomy and astrophysics can only be understood in terms of visual representation. By creating simple, elegant (and edible) metaphors […]

Today on the arXiv: Light echo gives insight into SNIa dust environment

Posted on Oct 12, 2016 in astro-ph, Research, universe

I noticed this interesting paper using high resolution, multi-epoch images from Hubble to study the time evolution of the aftermath of the explosion of SNIa SN204J, which went off in 2014 in the nearby galaxy M82 (a mere 11 million light years away). The data show the presence of a radially expanding light echo, as well […]

Today on the arXiv: how to measure the intrinsic CMB dipole, and radio emission from DM in the Coma cluster

Posted on Oct 6, 2016 in astro-ph, Research, Science

Elena Pierpaoli and her collaborator Slavash Yasini come up with a clever way of measuring the intrinsic CMB dipole, and disentangling it from the much bigger dipole induced by the Earth motion with respect to the CMB rest frame. The key idea is that leakage of the intrinsic dipole into the monopole and quadrupole induces […]

Today on the ArXiv: How to ride a light beam to the stars, and how not to analyse distance indicators

Posted on Oct 3, 2016 in astro-ph, News, Research, Science

Today on the arXiv, a nice analysis of how to design a solar sail in such a way that the light beam powering it is prevented from rocking it side to side, and hence destabilising it. The key idea is to use a spherical sail (rather than conical designs as previously proposed) and a multi-modal laser […]

Today on the arXiv: Prospector-alpha opens the way to high-accuracy photometry-based estimation of galactic properties

Posted on Sep 30, 2016 in astro-ph, Research, Science, universe

There is a terrific paper on today’s arXiv: The Prospector-alpha code is an impressive new approach to estimating a large number of important physical parameters of galaxies, including indicators for the galaxy’s star formation history, its metallicity, its mass and dust content. The code contains a large number of free physical parameters (describing star formation […]

Today on the arXiv: from light bulbs to 2 trillion dark matter particles simulations in 75 years

Posted on Sep 29, 2016 in astro-ph, News, Research

Today, Martin White suggests using a density-dependent correlation function as a tool to help distinguish General Relativity from modified gravity theories. The N-body simulation Zurich group shows impressive results from a cosmological simulation involving 2 trillion (2 x 10^12) particles, which they run on the Swiss Supercomputer in Manno using GPU-accelerated nodes, and benchmarked with […]

Bad news for LISA and Dark Matter line emission from the Galactic Centre

Posted on Sep 27, 2016 in astro-ph, Research

Today on the arXiv (arXiv:1609.08093) Camille Bonvin and collaborators (whom I know well from my days in Geneva) rule out the possibility to use the distortion in the gravitational waves chirp signal to measure the acceleration of the universe. They find that the peculiar acceleration is much greater and therefore would (1) wash out the […]

Why Society Needs Astronomy and Cosmology: a Gresham College Guest Lecture

This is the text accompanying a Gresham College Guest Lecture I gave on March 15th 2016. Audio recording of the lecture: Video of the lecture available here “One day, Sir, you may tax it!” In 1850 the Chancellor of the Exchequer, William Gladstone, reportedly visited Michael Faraday’s laboratory at the Royal Institution of Great Britain. […]

Papers of interest on the arXiv today – Sept 26th 2016

Posted on Sep 26, 2016 in astro-ph, Bayes, Research

Two interesting papers on the methodology side today: A ML source detection method that detects ultra-faint streaks below the pixel level noise (arXiv:1609.07158). They call it “ML” but in reality it uses MCMC to look at the Bayesian posterior (which is arguably a good thing!) and even Bayesian model comparison (in the BIC variety) to determine […]

Butchery or beauty? Explaining complex science using only the most common 1,000 words in English

Posted on Sep 23, 2016 in Outreach, The Edge of The Sky, universe

A version of this post appeared on the British Council’s VOICES blog on Nov 12th 2014 Would you try and cross the South Pole wearing only flip-flops? Or row across the Atlantic on an inflatable swimming pool? Or describe the beauty and mystery of the Universe using only the most common 1,000 words in English? As a […]