This week the team at I-LOFAR has been excitedly undergoing preparations for the upcoming Perseid Meteor Shower. Saturday night, 12th August 2018, is due to have the highest level of meteor activity with an expected 10 meteors per minute!

What is a Meteor Shower?

Meteors, more commonly known as “shooting stars”, are in fact small pieces of rock that have broken away from asteroids or comets due to collisions or extreme heating caused by their tremendous velocities. The small rocks enter Earth’s atmosphere and the resulting drag or air resistance of the air particles leads to further heating. This heating produces a huge glow which we can observed from the ground. A “shower” of meteors is caused when a comet passes especially close to the Sun & Earth inducing a large amount of heating and break up. In the case of the Perseids, Earth is passing through the dust and debris left behind the comet Swift–Tuttle.

How does LOFAR Detect Meteors?

I-LOFAR is hoping to observe the Perseid Shower using two different methods.

1. The first is called “passive radar”. This uses radio antennae to detect reflections of military/aeronautical radar off the plasma trail of the meteor. I-LOFAR will be trying to observe the reflection from a French radar used to monitor satellite orbits, called GRAVES, at 145 MHz.

2. The second method of meteor detection is by measuring direct emission from plasma in tail below 60 MHz as was done here by the Long Wavelength Array.

I-LOFAR has also teamed up with scientists at Dunsink Observatory, in collaboration with the Nematode network, who are planning on observing the event using two optical cameras with 30×30 degree FOV looking south and southwest, as well as a Yagi all-sky antenna tuned to GRAVE at 145 MHz.

What will we Learn?

From these observations I-LOFAR hopes to to determine the number of meteors per minutes, how fast they were traveling, from where the originated and where they were going in the plane of the sky.

How can I Observe the Perseids?

The Perseids will be most active on the nights of the 11th-12th & 12th-13th August 2018 and can be see with the naked eye. Get as far away from light pollution as you can and simply look up! Count and see if you can get 10 in a minute. And don’t forget to tune back in the coming days to see how the I-LOFAR team got on!

For more information and live updates on progress, keep an eye on the @I_LOFAR, @DunsinkObs and @nemetodemeteor Twitter feeds.

Transient Buffer Boards (TBBs) are a part of I-LOFAR’s data computation hardware that allow signals from the sun, stars and other astrophysical objects to be recorded at one of the fastest time resolutions possible. They can show us how the sun and stars change at the nanosecond scale.

To do this, TBB data must be recorded to cluster of computers so that the large amount of data can be stored. The total amount of data all 12 of I-LOFAR’s TBBs can hold is 384 GB, which is only 5 seconds worth of observations if all 96 antennas are used. Not only does the cluster need to store large volumes of data, it has to write it fast enough so that it doesn’t get lost before more data comes in. The TBB data cluster in our control room in Birr writes data to a fast, 46 TB storage node.

The picture above shows the TBB cluster in the control room. While it may not look pretty, it offers researchers in Trinity College Dublin the chance to observe the fine structure of radio bursts from the sun at the highest time resolution that has ever been done before. This will allow them to solve unanswered questions about energy release and particle acceleration on the sun. The fat silver unit at the top (WN104) is the fast storage node where all the TBB data is stored while the smaller units beneath it will be used in the future to process this data to look for new phenomena in the sun’s atmosphere.

The Irish LOFAR telescope at Birr reached a major milestone on March 6, 2018, when is was used for the first time to observe a nearby flare star called “CN Leo” as part of an International LOFAR Telescope (ILT) observing campaign.

The international team, which includes Irish astronomers Stephen Bourke and Aaron Golden, aim to “catch” a stellar flare exploding in the star’s atmosphere, and to use the I-LOFAR and ILT to understand how such flares evolve and how they compare to solar flares.

CN Leo is a small, red dwarf star about 7.9 light years away in the constellation Leo, and is likely to possess a planetary system. In fact, we now know that the vast majority of stars in the galaxy that have planetary systems that could harbour habitable planets orbit red dwarf stars like CN Leo, so a really important question to answer is whether or not such planets could survive the really very powerful stellar flares we see from many of these red dwarfs.

Studying the way in which such stellar flares occur and how they interact with their local environments using I-LOFAR and the ILT offers a new window on this important area of astronomy.

The I-LOFAR observations were taken as part of LOFAR proposal LC9_040 “A search for aurora on nearby flare stars using LOFAR”, and also involved simultaneous observations using the e-MERLIN radiotelescope in the UK, the Liverpool Telescope at the Roque de los Muchachos Observatory in the Canary Islands, and NASA’s Neil Gehrels Swift Observatory.

Stephen Bourke is based at the Department of Space, Earth and Environment, Onsala Space Observatory in Sweden, and Aaron Golden is at the School of Maths in NUI Galway, and is a visiting astronomer at the Armagh Observatory and Planetarium.

I-LOFAR is supported by Science Foundation Ireland, the Department of Business, Enterprise and Innovation and many others.