Wildfires From Space: Part III — The Bobcat Fire near Los Angeles

Posted on Thu 15 October 2020 in wildfires

The Bobcat Fire just north of Los Angeles one of the numerous wild fires which affected the US West Coast in recent weeks. The fire started on September 6th, 2020, and burned more than 110,000 acres.

To visualize the impact of the fire, I mosaicked two recent true-color images …

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Wildfires From Space: Part II — The SCU Lightning Complex near San Jose

Posted on Mon 28 September 2020 in wildfires

The SCU Lightning Complex east of San Jose is one of several significant wild fires which affected the US West Coast in recent weeks. The fire started on August 16, 2020, and burned nearly 400,000 acres over a period of several weeks.

To visualize the impact of the fire …

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Wildfires From Space: Part I — The CZU Lightning Complex in the Santa Cruz Mountains

Posted on Sat 26 September 2020 in wildfires

The CZU Lightning Complex in the Santa Cruz Mountains is one of several significant wild fires which affected the US West Coast in recent weeks. The fire started on August 16, 2020, and burned more than 80,000 acres over a period of several weeks.

To visualize the impact of …

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The exponential spread of the Ebola virus

Posted on Wed 15 October 2014 in data

Three weeks have passed since my original post, and Ebola has continued to spread exponentially since. At the present rate, the number of reported cases of Ebola appears to double every 29 days.

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Science using Twitter: when do people see spiders?

Posted on Tue 30 September 2014 in data

It has been a mild autumn in the UK, which has led researchers to predict that we may see more spiders than usual this year. The theory goes that mild weather causes more insects to be around, which in turn implies that there is more prey for our eight-legged friends …

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Citizen Meteor Science: Summary of the 2014 IMO Conference

Posted on Wed 24 September 2014 in meteors

I had the pleasure to take part in the International Meteor Conference this weekend, which is an annual meeting organised by the International Meteor Organisation (for which I am a council member). The IMO is an international non-profit organisation which exists to encourage international cooperation between amateur astronomers in the …

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219 million stars: our new atlas of the visible Milky Way

Posted on Tue 16 September 2014 in astronomy

Over the past decade, my colleagues and I have been working very hard on a mission to create the most detailed atlas ever made of the visible part of our home galaxy, the Milky Way. The result of this labour is a brand new catalogue detailing the properties of no …

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Asteroid (22275) Barentsen

Posted on Tue 22 July 2014 in astronomy

I've had the pleasure to learn that a small piece of the solar system is now named after me: asteroid 22275 has been formally named "Barentsen" by the International Astronomical Union. The announcement was published recently in Minor Planet Circular 88763, which named several dozen asteroids after scientists who have …

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Martian Nyan Cat

Posted on Wed 25 June 2014 in astronomy

Today I participated in the Hack Day at the UK National Astronomy Meeting in Portsmouth. Apart from working on a few silly side projects, my colleagues Jeremy Harwood, Leigh Smith, and I decided to produce a video which might well change the face of astronomy outreach and visualisation forever.

The …

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Mapping the Milky Way's dust

Posted on Tue 03 June 2014 in astronomy

In recent months, my colleagues and I have been working very hard on compiling a massive catalogue which details the position and brightness of roughly 200 million stars located in the northern part of the Milky Way. The catalogue is based on a huge set of images which we collected …

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Map: where can you see the 2014 Camelopardalids from?

Posted on Tue 20 May 2014 in meteors

There might be an outburst of the Camelopardalids meteor shower on May 24th near 7h Universal Time (UT). If you live in North or Middle America, you will want to keep an eye on the sky in the night from Friday on Saturday for one or two hours surrounding 7h …

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Annual variations in the jet stream (video)

Posted on Mon 17 February 2014 in climate

The weather has been unusual in the past two months: extremely wet and windy in the UK whilst very cold and snowy in the United States. Such large-scale weather patterns are naturally linked to variations in the global atmospheric circulation. It is hence no surprise that there is much talk …

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Social Comet ISON Statistics

Posted on Mon 02 December 2013 in comets

Users of Twitter posted up to 12,000 messages per hour during Comet ISON's perilous encounter with the Sun last Friday. Events like this provide us with an opportunity to understand the demographics of the audience exposed to astronomy through social media.

Using the public API provided by Twitter, I …

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Outburst of the Daytime Craterids meteor shower

Posted on Wed 28 August 2013 in meteors

I am currently attending the Meteoroids 2013 conference in Poland. At the meeting, Prof. Peter Brown has just alerted us to the fact that the Daytime Craterids meteor shower has unexpectedly been detected by the Canadian Meteor Orbit Radar (CMOR) this morning. You can see the radar detection for yourself …

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Perseids 2013 global observing results

Posted on Tue 13 August 2013 in meteors

The annual Perseids meteor shower peaked last night between 16h00m and 18h00m UT (12th August 2013). The peak ZHR was about 147 ± 17 meteors/hour.

The graphs below show the visual activity graphs, which I have been generating for the International Meteor Organization during each major meteor shower since 2006 …

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Getting ready for Gaia

Posted on Tue 06 August 2013 in astronomy

Gaia is one of the most ambitious space missions of the decade. Twitter has a lot of talk about it this morning, after one pundit started using the hashtag #NRFG - "Not Ready For Gaia".

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Does rainfall affect food prices in Kenya?

Posted on Mon 05 August 2013 in data

Last week I had the pleasure to attend the first "London DataDive" organised by DataKind UK; a non-profit organisation which aims to bring data scientists and social organisations together. The noble idea behind DataKind is that charities and public bodies often sit on a pile of data which might be …

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Watch out for the 2013 gamma-Delphinids

Posted on Fri 07 June 2013 in meteors

On 11 June 1930, three meteor observers in Maryland (USA) witnessed a flurry of shooting stars originating from the constellation of Delphinus. The mysterious meteor shower, called the gamma-Delphinids, lasted less than 30 minutes. The shower had never been seen before, and it has never returned since... until this year?

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Is Java freezing your system? Tune the garbage collector!

Posted on Tue 26 March 2013 in computing • Tagged with Aladin, Java, Topcat

I regularly open huge images and tables (>1 GB) in interactive Java-based (astronomy) software such as Aladin and TopCat. Because of the way memory allocation works in Java, the area where objects reside in memory (called the heap) needs to be reserved up front using Java's -Xmx switch. Hence I …

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Comet PanSTARRS attracts 2x more men than women?

Posted on Wed 20 March 2013 in comets

Two weeks ago, I posted an animation on YouTube showing where Comet PanSTARRS would be visible. The video attracted more than 15 000 hits, and although this is not a proper statistical analysis, I would like to draw attention to an interesting result in the demographic analytics provided by YouTube …

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Map: when can you see comet PanSTARRS?

Posted on Tue 05 March 2013 in comets • Tagged with C/2011 L4, Comet, Pan-STARRS

Comet C/2011 L4 (PANSTARRS) has brightened dramatically over the past week and is now visible with the naked eye from the Southern Hemisphere. Pan-STARRS is moving north rapidly and will become visible across Europe, North America and Asia from Thursday 7 March onward. The comet is expected to reach …

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How frequently do large meteoroids hit us?

Posted on Fri 15 February 2013 in meteors • Tagged with Chelyabinsk, Fireball

The internet is buzzing about a fireball which caused a powerful sonic boom over Chelyabinsk in Russia, injuring hundreds. A question asked by many is: how common is such event?

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From where can you spot 2012 DA14?

Posted on Tue 12 February 2013 in asteroids

On Friday 15 February, a 50-meter asteroid named 2012 DA14 will approach Earth to within a distance of just ~28 000 km. The internet is buzzing about this near-miss because the object is expected to become brighter than 9th magnitude for approximately 3 hours (18h00-21h30 UTC), peaking at a brightness …

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How do you organise $HOME?

Posted on Tue 30 October 2012 in computing

Home directories often turn into spooky graveyards of random files, temporary directories and images of lolcats. It takes courage to delete the mess, because there may be one or two important files hiding amongst the pr0n. As a result, many scientists have grown afraid to run ls ~ in public, fearing …

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Footprint of the IPHAS Galactic Plane survey

Posted on Mon 22 October 2012 in astronomy • Tagged with IPHAS

As part of my post-doc at the University of Hertfordshire, I'm helping to calibrate, release and exploit data obtained by the INT Photometric H-Alpha Survey (IPHAS). This is a 1800 deg2 optical survey of the Northern Galactic Plane, carried out in the narrow-band Hα and broad-band Sloan r'/i' …

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Visual & video observations of the 2012 Draconids outburst

Posted on Wed 10 October 2012 in meteors

As reported in my previous post, the Draconids meteor shower showed an exceptional peak on the evening of 8 October 2012 near 17h UT. The peak was very pronounced in data from the Canadian Meteor Orbit Radar (CMOR), which reported rates up to 2300 meteors/hour. In fact, I am …

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Draconids show outburst (again!)

Posted on Mon 08 October 2012 in meteors

For the second year in a row, reports are emerging about a major peak in the activity of the Draconids meteor shower. Radar observing stations in Canada and in Germany reported up to 1000-2000 meteors/hour between 16h and 18h UT on 8 October 2012. Evidence for an outburst is …

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Posted on Sat 06 October 2012 in misc

To celebrate the completion of my PhD and start of a post-doc, I've decided to start publishing bits and pieces of research on a blog. I'm hoping this will encourage me to write about results more frequently, hence achieving more scientific output and interaction than I would obtain through peer-reviewed …

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