We’re delighted to announce the start of a new meteorites project called Shooting Stars @ the Natural History Museum that aims to observe meteors over the UK.

Meteors (also known as shooting stars) are dust and rocks from space that generate a bright trail in the sky as they pass through the atmosphere. When a piece of rock enters Earth’s atmosphere it is moving very quickly (11 – 70km per second). As it falls to Earth the friction from the air causes it to glow and disintegrate. A very bright meteor is called a fireball. If the fireball is large enough (usually >1m), some of the rock may survive the fall and land on the Earth’s surface, which is when it becomes known as a meteorite.

Meteorites record 4.5 billion years of solar system history, but we rarely know where exactly in the solar system they came from. We think most are from asteroids, and some may even be from comets. One way to confirm this is to know a meteorite’s original orbit, which can be estimated if its fireball is witnessed from multiple locations. However, out of a collection of ~50,000 meteorites worldwide, fewer than 10 have been observed falling to Earth in enough detail to accurately calculate their orbit.

My desk is getting crowded but we now have everything we need to start watching the skies!

To increase the chances of seeing a meteorite while it is falling to Earth, a number of digital camera networks, dedicated to detecting meteors and fireballs, have been set up around the world. Some use highly sophisticated cameras and software, whilst others are more low-tech affairs.

Our Shooting Stars project will contribute to these networks by using two CCTV cameras to search for meteor fireballs above the UK. One camera will be placed on the roof of the Natural History Museum in South Kensington, and the second will be located at our Tring site to avoid the effects of light pollution in central London.

Our new toy! This is one of the CCTV cameras that we will use to search for meteors and fireballs above the UK.

Over the last few months we have received almost daily deliveries of cameras, lenses, cables and computers. We’re hoping to have the first camera built and ready for testing in the next couple of weeks, so check back here and keep an eye on our twitter account for the latest updates.

A fish-eye lens will be attached to the camera to give us a wide-angle view of the night sky.

Museum scientists Ashley King and Anton Kearsley have co-authored an article published in Science on 14 August 2014 on the first laboratory analysis of interstellar dust grains.

Have you ever wondered what exists beyond the solar system? Most people think space is empty, but in actual fact the vast regions between the stars, the interstellar medium, is full of tiny dust grains. Until recently the only way to study this dust was to use telescopes and we knew very little about its size, composition and structure. However, a new study has now described the first successful laboratory analysis of dust grains from outside the solar system.

The interstellar dust was returned to Earth by NASA’s Stardust mission. Launched in 1999, the spacecraft had a collector made of aerogel bricks (the lightest solid material on Earth) in a frame made of aluminium. This was specially designed to preserve materials impacting into it at very high speeds (faster than 6 km/s). One side of the collector was used to capture materials from the comet Wild 2, the other to capture interstellar dust passing through the solar system. The sample-return capsule arrived safely back on Earth in 2006 and, following initial analysis of the comet grains, work began on the interstellar side.

The Stardust sample-return capsule landed in the Utah desert on 16 January 2006. The capsule was transported to Johnson Space Centre, Houston to be opened in a clean facility (Image courtesy NASA/JPL-Caltech).

The study reports the findings of a 6 year collaborative effort between 66 scientists (including myself and Anton Kearsley at the Museum) working in 36 laboratories in 7 countries. The team also received help from >30,000 members of the public who identified impacts tracks by searching through thousands of digital microscope images as part of the citizen science program Stardust@home.

It turned out that most of the impact tracks and craters were caused by debris from the spacecraft or dust from within the solar system. However, 7 grains are likely to be of interstellar origin and, using the experience gained from examination of the comet particles, the team developed methods for extracting, handling and analysing the precious interstellar samples, finding some unexpected results along the way!

Tiny dust particles impacting into the collector (about the size of a tennis racket) produced tracks in the aerogel (right) and craters in the Al-foils (Image courtesy NASA/JPL-Caltech).

The interstellar grains are very small, typically weighing a picogram (a millionth of a millionth of a gramme) or less, and have different compositions and structures. One of the biggest discoveries is that the grains have at least partly crystalline structures, which is surprising as most people thought that the crystallinity should be destroyed in interstellar space by irradiation.

Sample-return missions such as Stardust are therefore allowing us to answer big questions about the formation and evolution of galaxies and solar systems by studying minute amounts of material in the laboratory. The Science paper has just hit the headlines today but, hopefully, there's a lot more to come in this story.

Hi all! Natasha here again, raring to tell you all about a most excellent trip that I’ve recently returned from. It was my first experience of the US and boy was it a good ‘un. Killing two birds with one Texan stone, I first went on a short course on geological applications for computed tomography (CT) in Austin, and then on to Houston for a visit to the NASA Johnson Space Center.

Micro-CT is a remarkable (and pretty novel) technique that uses X-rays to image specimens in three-dimensions, giving us a non-destructive way to see what’s inside. I use it to look at extraterrestrial material, but the scanner at the Museum gets used for all sorts! Sometime I'll do a more detailed post that goes into the physics of it all, but for now, back to the Lone Star State.

So my experience can be summed up in three words – humid, delicious and rocky! Everything is bigger in Texas. The cars (read pick-up trucks), the cakes, the personalities! Arriving into 40°C heat in Austin, my glasses immediately steamed up. After a short shuttle bus to the hotel, I was excited to meet my roommate for the duration of the course, a lovely PhD student studying drill cores with CT at the University of Florida.

Course on CT scanning

The short course was run by the High Resolution X-Ray CT Facility at the Jackson School of Geosciences (UTCT) in the University of Texas at Austin. This fantastic lab has been doing pioneering work in the geological applications of CT for almost 20 years. As well as getting a very helpful tutorial on their in-house software and talks on successful projects they have done, we also had the opportunity for a tour around the labs. UTCT has two CT scanners, which are optimised for different sizes and types of sample, including one instrument with detectors on microscope objectives. This means they can sort of ‘zoom in’ to features inside the specimen and get very high resolution images! Luckily they also have air conditioning in the lab otherwise I’m sure I’d have passed out from the heat!

Ryan in the computer lab, learning how to use Blob3D.

That evening, all the course delegates were invited to a marvellous barbeque at the course director’s house, with home-smoked brisket, and my first Texan ribs! As well as enjoying dinner, I was dinner for certain unwelcome party guests… I left that night with about forty mosquito bites! 

Tuesday and Wednesday were likewise spent in workshops and tutorials on both CT hardware and software. One of the most important and useful aspects of attending the course was the chance to spend time with other rock-minded people, to share ideas on how to tackle problems or artefacts in the data, and to make contacts for future collaboration or discussion. We also managed to sneak in a couple of World Cup games along with a quick craft beer tasting walk through the city!

Congress Bridge in Austin and the crowds awaiting the awakening of the million or so bats that live underneath.

Oh, and to continue the gastronomic theme, I tried a chimichanga, Detroit-style pizza, possibly the best pulled pork sandwich I’ve ever had, and breakfast burritos. Mostly yum!   

This is a chimichanga, a deep fried burrito, soaked in cheese. Can’t say this one went down well!

As if often the case when you’re having fun, the days passed quickly, and it was soon time to leave Austin. I headed on to Houston for the next stage of the trip.

A trip to NASA

The Johnson Space Center is NASA’s base for human spaceflight training and flight control, and houses their Astromaterials Research and Exploration Science department. This means that all the astronauts are based there, and all the Apollo samples, Antarctic meteorites and samples collected during the Stardust and Genesis missions are kept there! It is possibly the most awesome facility that I could ever imagine.

The Space Shuttle Endeavour flying over the Johnson Space Center on a Boeing 747 carrier aircraft. Copyright NASA.

The key reason I went to NASA was to visit Ryan Zeigler, the Apollo Sample Curator. Ryan is responsible for looking after all the rocks, soils and cores brought back by the Apollo astronauts on the six missions that landed on the Moon. Back in February, he brought four of these samples, from Apollo 14, 15 and 16, to the Museum, and we CT scanned them here together in the Imaging and Analysis Centre.

We haven’t written up the results yet, but all four scans were very interesting, showing different textures and inclusions. One of the most exciting finds was that of a very large clast of basalt in an Apollo 16 breccia (a rock made up of fragments of other rocks or minerals). Below is a visualisation I made of the CT data, which shows the outline of the sample and where the clast is located inside (the green mass). This kind of image is invaluable for curators who would like to know exactly where to slice into the rock to expose features of interest for science. The sample is about ten centimetres across.

A visualisation of the location of a basalt clast within an Apollo 16 breccia, made using the Drishti program.

Blimey, that’s a long post already and I’ve barely got on to the coolest stuff that I saw and the rocks that I got to hold! I’ll leave it there for now but check back soon, as I’ll be doing another post all about the Lunar and Meteorite Laboratories! Here’s a taster:

A lunar basalt, collected by Apollo 11. The only rock to have been brought from the Moon then taken back into space for a trip on the International Space Station.

Lastly, if you’re ever in Texas, check out the ribs at Rudy’s!