Saturday morning started with a talk by Mark McCaugheran on some of ESA’s recent major projects.
He started by talking about Gaia which was launched in 2013 to map and provide distances to stars in our own Galaxy. Gaia will not only measure the distance to these star but also their real motion across the sky. To do this it needs to be able to measure to an accuracy of a few micro arc seconds, equivalent to the width of a human hair at 2,000 Kilometres.
Gaia has the largest camera ever put into space made up of 106 CCDs. The effect of this is that the images are too large to download; instead they only download the positional information extracted from the images. Gaia is a five year mission but they will be publishing initial data release this year with a full data release in 2017. Unlike other missions the data will be fully released to the general public at the same time it is being made available to the scientific community. Since launch Gaia has made:
- 326 billion astrometric measurements
- 76 billion photometric measurements
- 7 billion spectroscopic measurements
The second mission Mark dealt with was the LISA Pathfinder. This is a technology demonstrator to show the capability to measure gravity waves. The full mission will involve three spacecraft floating 1 million Kms apart linked by lasers measuring the slightest movement in their payloads caused by gravity waves. For this to be a success it needs an accuracy of 1 picometre, equivalent to the width of a human hair at 40,000 Kms. The pathfinder is testing this capability by placing to lumps of gold 38 cms apart and holding them to this accuracy over a period of a year. The mission launched in December 2015 and the experiment itself will be starting in a few weeks time. We have spoken about this at our meetings previously and will no doubt come back to it during the year.
The final mission Mark covered was Exo Mars 2016. This is a joint mission between ESA and the Russian space agency which is designed to demonstrate an ability to land on Mars as well as measuring trace gasses in the atmosphere. This mission is a pathfinder for the 2018 mission which aims to land a rover on Mars to drill deeper into the planets crust than before looking for chemicals that could show signs of life.
Having run 10 minutes over time Mark was chased off the stage to make way for the next speaker Debbie Lewis an emergency planner talking about what we could do in the event of an asteroid strike. Debbie briefly covered asteroid strikes from those which wiped out the dinosaurs through to the Chelyabinsk strike a couple of years ago which did some structural damage as well as injuring about 1500 people. She pointed out that most of these injuries came from people going to the window to see what was happening and then being hurt by flying glass as the window blew in! So first lesson, stay away from the Windows.
She outlined the work that has gone into detecting Near Earth Objects over the last few decades which has given us a much better appreciation of what is out there although there are plenty of small objects like the Chelyabinsk impact or that we do not know about. Whilst there is a lot of work going on to identify threats virtually nothing is being done with regard to protecting people or dealing with the consequences of an impact in a populated area. In the UK asteroid strikes are not even covered by Civil contingencies whilst the attitude of FEMA in the United States is “we’ll just move people to tented refugee camps”. We can all see how well that is working elsewhere. So it is no surprise that Debbie sounded somewhat exasperated about the whole thing.
Finally we had Michelle Heurs of the Max Panck Institute talking about looking for gravitational waves and, in particular, listening for them.
Michelle outlined the ways in which gravitational waves can be detected by using sophisticated developments of the Michelson interferometer such as advanced LIGO as well as talking about the e-LISA space mission which will not now launch until 2034. However one of her main points was that whilst we can look for gravitational waves in the electromagnetic spectrum they can also be found in the audio spectrum and she played a number of simulations of what gravitational waves should sound like if found and argued that we need to bring our other senses to bear in these sorts of issues.
However what most people were interested in was the one thing she would not talk about. As you are probably aware rumours abound that LIGO has made a discovery of gravitational waves and a press conference is scheduled for 11 February. Michelle is part of that team but is saying nothing, despite having been played with copious amounts of alcohol the previous evening by Stuart Clarke. So it seems we will have to wait until next week to see if there is any truth to the rumours.