Several folks here at Cardiff were on the team, so I’m sure you’ll see them flitting about in the background twiddling knobs and such. I know one team member who was interviewed but was too rude to make the final edit.

The BLAST page on the BBC website tells you the various dates it will be broadcast, and of of course if you’re in the UK you can catch it for some time on the amazing iPlayer.

[Official BLAST movie website]

The problem is that the detector arrays for the device are currently at the NIST (National Institute of Standards and Technology) lab in Boulder, Colorado where a ‘radiation incident’ has taken place. Contamination from plutonium means that no one can enter the lab and the detectors are currently inside.

The incident is described on the NIST website, which says that “a small plutonium spill occurred on June 9″. The sample that is thought to have caused the leak would have contained just one-quarter of a gram of plutonium. This seemingly tiny portion of radioactive material was accidentally spread around by a lab worker who also used a sink to wash his hands while contaminated.

The lab has since been inspected and many surfaces are contaminated including “the floor [and] various tabletops and surfaces, consistent with a spread of material by hands and shoes”. NIST are working with experts and hope to have the situation resolved soon.

Meanwhile, SCUBA-2 has to wait. It has now been two weeks and as soon as the science team can get their hands on the arrays they hope to begin the next phase of work and try to bring to life a device which many have been waiting for with anticipation.

SCUBA-2, and its orbital cousin Herschel, will begin a new era for the science of star formation and submillimetre observing. You’ll hopefully be hearing a lot more about both these instruments right here in the weeks and months to come.

There is a lot more to the universe than the light you and I can pick up with our eyes and brains. Although its a shame that we can’t see them naturally we can use technology to reveal the wavelengths of light normally invisible to us. Visible light is only part of the electromagnetic spectrum (a very small part) and I thought it would be interesting to see some familiar objects in unfamiliar ways.

The electromagnetic spectrum is usually split into seven parts: the radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray. You can find a good schematic of the EM spectrum over on Wikipedia. We obviously see things in the visible, but some creatures, such as bees, see some of the ultraviolet (one reason there are so many purple flowers). Here is a picture of a Geranium in the visible and then the UV. You can find more images like these, for all kinds of flowers over at this website.

But this is an astronomy blog and so here are some objects seen in multiple wavelengths. Some of them may surprise you. First up is the Moon. Here we have it in the radio, microwave, infrared, visible, ultraviolet and x-ray.

The infrared image (top right) shows various bright spots. These are warm areas on the Moon. The brightest spot, in the bottom-center of the Moon is the crater Tycho, which also shows up brightly in the visible and UV images. The X-Ray picture is from ROSAT (bottom-right). Here we see the Moon shown in its quarter phase to highlight that it is only reflecting X_Rays from the Sun and not giving any off itself. The Submillimetre (microwave) image (top-centre) was taken using the SCUBA camera on the JCMT in Hawaii. This is a camera normally used to image dust in nebulae and faint galaxies.

Next let’s look at something more exotic but still familiar, the Andromeda Galaxy. Also called M31, this is closest neighbouring galaxy in the wider universe and is just about visible from a good site. We are seeing this in the radio, microwave, infrared, visible, ultraviolet and x-ray.

You can really start to see now why observing objects in different wavelngths can tell us something about them that we didn’t know before. The different details in each image are coming from different parts of the galaxy. In the top-center image, which is taken at 175 micrometres, we are seeing the dust lanes between stars in the galaxy. The X-Ray image in the bottom-right shows us only the extremely energetic objects, which as we can see, are located predominantly toward the centre.

Another easy to spot object, which you may know of is M45, also known as the Pleiades or Subaru. Once again here it in the radio, microwave, infrared, visible, ultraviolet and x-ray.

The most impressive image here in my opinion is the X-Ray image from ROSAT (bottom-right). It looks to me like something from Doctor Who. It is also interesting to note that M45 doesn’t show up as much in radio frequencies. In the top-centre image we can see only some of the stars. This is because M45 is a young cluster and some of the surrounding dust still obscures the stars in this far-infrared image.

I thought I’d save the best til last: here is the Earth. Now its tricky to get pictures of our own planet – because we’re on it. We’re lacking in any good radio images of the Earth because you can do radio astronomy perfectly well without putting telescopes in space. However I really like these images because they really took me by surprise. In order, these images show the Earth in infrared, visible, ultraviolet, extreme-ultraviolet, x-ray and gamma rays.

The first image shows the infrared emission on the Earth from water vapour. Like the two UV images, this picture is from an extensive network of Earth-observing satellites that are attempting to investigate how our planet operates. Tectonics, oceanography and climate change are just three of the many topics being studied to ever-more depth by NASA, ESA and researchers the world over. The X-Ray image (bottom-centre) shows an aurora on the Earth’s north pole. Other than this high-energy interaction between the atmosphere and the Sun, the Earth seems to be invisible at this wavelength.

Finally we have the gamma ray image (bottom-right). What you’re seeing here are extremely high-energy particles, mostly from outer space, reflecting off the Earth’s atmosphere. The edge of the globe is seen to be much brighter than the center because cosmic rays hit the atmosphere at a shallow angle and are more likely to create detections. There is an imbalance btween the East and West due to the Earth’s magnetic field, which is asymmetrical.

I hope you’ve enjoyed this little collection, if you know of any other cool multiple wavelength images – astronomical and otherwise – then please leave a comment with a link.

SCUBA-2 can scan the sky much faster than SCUBA and will allow researchers to measure the properties of protoplanetary disks around young stars, amongst other things. Exciting stuff. It is however very big.

Whereas SCUBA was comparable to a hefty water-heater, SCUBA-2 is more like a minivan. Mostly this is because of the cryostat that is required to keep the technology inside SCUBA-2 at a very low temperature. This technology has been developed principally in Edinburgh but also in Cardiff as well a few other places.

I saw SCUBA-2 in Edinburgh in 2006 and noted its large size at the time. When I observed at the JCMT last November (2007) I asked how on Earth they intended to get the the very expensive SCUBA-2 inside the very expensive JCMT without damaging either. The answer gave was that it would be tricky, and now thanks to a series of photos from April 2nd and 3rd I know what they meant.

The full gallery of 600 photos can be found on the Joint Astronomy Centre‘s JCMT pages. There is also a fairly large animated GIF file (22MB) if you would like to see the installation in action.

SCUBA-2, as the name might suggest, is the successor to SCUBA which stands for Submillimetre, Common-User Bolometer Array. What does that mean? Well basically this is a device that you connect to a telescope and then record images of the sky.

Its submillimetre because it will record information in the 850 micron and 450 micron wavelegnth regimes (i.e. 0.85 and 0.45 mm). Its common-user because a) lots of people can use it and b) it makes a nicer acronym than SBA. Its a bolometer because… well its a bolometer; and finally its an array of detectors put together to make the pixels of an image.

SCUBA-2 is hopefuly the camera which will provide me with data for my PhD thesis. I have been working with SCUBA data sine I arrived at Cardiff back in September last year. I may even publish a paper based on my work so far. However the data from SCUBA will look tiny compared to that which will come from SCUBA-2.

Two of my own images from SCUBA data. Both of these show star forming regions inside dark nebulae.

The new device is incredibly powerful by comparison to the original. The BBC News article states that it will be a thousand times for powerful, but there are many ways to measure ‘power’ in this kind of instrument. SCUBA-2 will be able to map the sky 720x faster than SCUBA. So where it used to take hours to obtain maps, it will now take minutes. SCUBA-2 has a field of view at least 13x greater than SCUBA, which means you get more in each map. SCUBA-2 is also going to be twice as good at detecting point sources, which means it is going deeper into the sky.

Left: SCUBA, which is about a metre and a half tall. Middle: Me leaning on SCUBA-2. Right: The receiver end of SCUBA-2.

SCUBA-2 is going to moved to the JCMT telescope in Hawaii in October where it will be fitted to the receiver of this 15m scope. This process takes months and afterwards the deice will have to undergo what is called commissioning, where it is essentially calibrated and readied for proper use. all in all we can expect the camera to be in full use in around a year or so if we’re lucky.

SCUBA-2 will be acting as pathfinder for the upcoming ALMA. ALMA is an array of submillimetre scopes in Chile’s Atacama desert – one of the highest and driest places on Earth. This array will use the surveys done with SCUBA-2 to go deeper than ever into space using an array of 76 telescopes which will combine to give a clarity of image 10x that of the Hubble Space Telescope.

V838 Monoceroti Expansion (Hubble)

It wasn’t anything interesting until it happened but the star V838 Monoceroti, which had simply sat in obscurity, flared up in 2002 to become 600,000 more luminous than our own Sun. It didn’t take long for the star to fade back into the darkness but the Hubble Space Telescope managed to get quite a few pictures of it during its active phase. (Click for animated version)

In this series of images you can see how the star’s outer layers were first expelled and then cut away by the powerful radiation from the star. The event was made even more interesting by the fact that a ‘light echo‘ was seen. During the expansion the object appeared to expand faster than the speed of light – the effect was however merely an astronomical optical illusion.

The Egg Nebula (Hubble)

Also known as CRL2688, the Egg Nebula shows a pair of mysterious ‘searchlights’ bursting out from a dense cocoon of dust surrounding a hidden, Sun-like star. We see the light escaping in the directions where the cocoon is thinner. Objects like CRL2688 are rare because they are in a phase of their evolution that is short-lived. Images like this one are very important to understanding how stars like our Sun will ultimately die.

The Sun in UV (SOHO)

[quicktime width="400" height="400"]http://www.orbitingfrog.com/blog/movies/SuninUV.mp4[/quicktime]

The surface of the Sun is far more active than most people would think. This ultraviolet video taken by NASA’s SOHO spacecraft gives brilliant detail. It allows us to see one full revolution of the Sun on its axis, which normally takes about 25 days. In this video you can make out large flares erupting from the surface and the striking magnetic loops that seem to whirl about them as they go. (Full 512×512 MPEG Here)
Red Square Nebula Nebula (Hale/Keck)

Discovered in 2007, this ruby-like nebula may be the result of two interacting stars. If one star is dying then the material from it may be dragged into a disc around the orbits of both objects. Material can then only escape from the system along the poles of the disc, resulting in two cones leading out of the stars. When viewed from the edge these cones seem like two triangles. Here the system is seen in the infrared. Structures like this are rarely seen in nebula but there is in fact a Red Rectangle Nebula which is less symmetric but still quite interesting to look at.

Abell 39 (NOAO)

Here we see an almost perfect planetary nebula that sits about 7,000 light years away in the constellation Hercules. The dot at the centre is the original star, which – as it died – released the expanding gas shell also seen clearly here. The ghostly appearance of the shell is due to the blue-green filter used to take the image, which picks out the oxygen emitted light at 500.7nm.

Saturn’s Rings (Cassini)

This marvelous panoramic view was created by combining a total of 165 images taken by the Cassini wide-angle camera over nearly three hours on Sept. 15, 2006. Cassini was sheltered from the Sun’s glare by positioning itself behind Saturn. Ring structures are revealed here in detail as they brighten substantially at viewing angles where the Sun is almost directly behind the objects. These observations allowed Cassini to detected two new faint rings.

The Horsehead Nebula Swallowed Something (SCUBA)

Observers used the JCMT submillimetre telescope on Mauna Kea in Hawaii to take this image of the familiar Horsehead Nebula, who’s outline can be seen here. When observed at 850 microns, we are seeing the cold dust at temperatures close to absolute zero. This dust is deep inside the optical nebula normally seen, which is transparent at this wavelength. It seems from the image that the Horse has swallowed a ‘lozenge’ which is in fact a region of dense dust that may be collapsing under gravity. In fact this could be a star system in the making.

Gomez’s Hamburger (Hubble)

Arturo Gomez found this odd object in 1985 and it became known as Gomez’s Hamburger for obvious reasons. It is actually a proto-planetary nebula, an earlier version of Abell 39 perhaps. The curves of light (the bun) are reflecting light from the star which is being obscured by a thick band of dust (the burger). The whole thing is only only a fraction of a light year across and located 10,000 light years away in Sagittarius.

The Solar Spectrum (NOAO)

If you could catch a rainbow and put it under a microscope you would see that it was not a continuous blend of colours. Along the width of it would be seen, scattered irregularly, dark patches. Atoms and molecules in the Sun’s atmosphere pick out specific frequencies of light and absorb them, diminishing their intensity by comparison. This images shows the spectrum of light from the Sun stretched out to make these absorption lines visible. We use the reverse of the idea (emission lines) when we make coloured lights. For instance, we excite sodium atoms to emit a signature orange light in street lamps. In this image you can see two prominent dark bands in the yellow-orange section which are the absorption due to sodium.

Update to This Entry

The Sombrero Galaxy in Infrared (Spitzer)

By looking at things in different wavelengths we can see much more than meets the eye. This image is a perfect example. Just as with the Horsehead image above we are seeing cooler material. This time it is dust in the Sombrero galaxy. The red ring is a thick band of dust encircling the whole galaxy. In the optical, this dust ring is what gives the Sombrero its distinctive black, obscuring line.

Oddities in the Orion Nebula (Hubble)

Deep within high resolution images of the Orion Nebula taken by Hubble we can see dark blobs. When you take a closer look you can see that these are like little flattened blobs. Some show a dim, red glow at their centres, others are just dark. These are proto solar-systems.

The red glowing is a protostars attempting to burst through and the dark disks are thick dust regions where one day planets may form. 6 billion years ago, this is what our Solar System may have looked from very far away.

There is something special about the Sun. At least that’s how we all think here on Earth. Truthfully though, the Sun represents just one type of star – a common one in fact – in a catalogue of stars that is seen to be fairly consistent all over the universe. Understanding where that consistency comes from, and where the trillions of stars and their planets come from, are two of the goals of an area of astrophysics called star formation.

How the Sun came to be in this neck of the galactic woods with its family of planets, dwarf-planets and other miscellany – including us – is certainly worth knowing. It is fortunate then that star formation is about to boom.

ESA’s Herschel space observatory (launching 2008) and the upcoming SCUBA-2 camera (that will be fitted to the James Clerk Maxwell Telescope in Hawaii, in 2008) are two examples of a handful of eagerly anticipated instruments set to produce more data than star-formation researchers have ever had. They will enable astronomers to see deeper than ever before into the murky depths of the dustiest regions of the galaxy, where stars are born. Many of these sites are the beautiful nebulae now so familiar thanks to images like those from Hubble. Others are huge, dark clouds that are too cold and dense to see, but give away their location by obscuring background light.

It is hoped that these new facilities with help answer several of the big questions facing astronomy. For example, why do stars form in clusters of hundreds or thousands? Why do they have the same catalogue of masses that is seen everywhere we look? What are the initial conditions of planet formation?

The physics involved crosses huge orders of scale. A good demonstration is this: imagine the Sun were a metre across. At this scale the nebula from which it formed would be the size of France! Incidentally that makes the Earth a mere pea. To compress all that material down by a factor of a million in size involves complex physics. In order to understand where we came from, you need to understand that physics.

As a discipline, star formation slots into almost all areas of astrophysics. For instance, in order to study galaxies you need to know what they’re made of. Even cosmology, often seen by its champions as being less ‘astro’ and more ‘physics’ has recently encountered a star-formation problem. In order to account for observations of stars that appear to be as old the universe itself, they need to explain how a population of stars could have formed so rapidly and so soon after the Big Bang. Whichever angle you look at it from, star formation is vital to modern astronomy.

Star formation is also important to you, personally. This isn’t just because the various stages of stars give you pretty objects like the Orion Nebula and the Pleiades (above) to look at with your telescope. Star formation tells us something very fundamental: we are all made of stardust. The Sun, planets and everything else around us were formed from the same giant cloud of material – most likely a cloud left over from an even older star when it died. Yet that same process creates a whole array of stellar classes and different planetary characteristics. Only star formation can tell us how all of this works.

NASA’s planned Darwin mission and ESA’s Terrestrial Planet Finder will both be able to resolve Earth-like planets around other stars. These, along with Herschel and SCUBA-2 will enable us to look at whole stellar systems from the outside, a perspective we have never had before. Observers will look at systems like our own at various stages of existence, from barely formed blobs about to start collapsing under gravity through to ancient star systems; we will even see planets in formation.

As a subject, star formation is set to explode. It will allow us to see ourselves better than ever before and to understand the origins of our existence. This is inspirational science, and definitely worth keeping an eye out for in the years to come.

HARP is the Heterodyne Array Reciever Programme and consists of a 4×4 grid of supercoducting detectors capable of detecting the submillimetre wavelgnths at which star formation seems to be best observed. ACSIS is the AutoCorrelation Spectrometer and Imaging System and is a scomples of electronics and processors which analyse the HARP data, as well as data from other instruments. When attached the 15m JCMT dish this enables researchers to study the motion of gas.

The instruments produce a 3D ‘cube’ of data. Essntially andi mage which has a third, wavelength, dimesion. Different molecules give off radiation at different wavelengths and also the motions of gas can slighty affect the precise wavelength valuesd as well. These two factors allow not only the chemical make up of the cloud to be determined but also the movements of those chemicals within the cloud to be traced.

HARP and ACSIS allow astronomers to see the motion of this gas with a clarity and precision not previously available at these wavelengths. Together they give the JCMT the powerful ability to record information in three dimensions. Unlike the previous generation of receiver systems, HARP/ACSIS can produce camera-like images of the sky across thousands of adjacent wavelengths simultaneously; forming a three-dimensional image set called a “spectral cube”. The wavelength dimension permits the telescope to sense molecular tracers as well as to detect the motions of the gas.

“HARP/ACSIS is revolutionising our view of star formation in the galaxy” – Dr. John Richer

The image shown below is of Orion in carbon monoxide. This is just one slice out of the data cube and all the slices together can be combined to form a movie. The gas in the south of the cloud is moving toward the observer, whilst in the north it is moving away. This is because the star forming region at the centre – the familar M42 Orion Nebula – is pushing the gas outward as the stars form inside.

The press release from the STFC also invluded some thoughts from astronomers i8nvolve din the field. Dr. Jane Buckle of the Cavendish Laboratory says: “Commissioning HARP and ACSIS took a lot of hard work and dedication, particularly from the JAC, the Cavendish Laboratory and UK ATC staff, but the new spectral imaging capabilities at the JCMT make this a very exciting time for star formation research.”

Dr. Bill Dent of the UK Astronomy Technology Centre in Edinburgh says:” We often find gas clouds many tens of light-years across containing hundreds of stars all forming simultaneously. With this new system, we can map the structure and measure the speed of the gas that’s forming all these new stars and, furthermore, do a chemical analysis, perhaps looking for regions rich in rare and exotic molecules. Before HARP/ACSIS arrived, it was just not possible to study and understand whole clouds in this way.”

Dr. John Richer has used the JCMT for 19 years to make spectroscopic observations of molecular clouds. “It used to be a painstaking and slow process. Now with HARP’s 16 sensitive detectors, we can take data at a much more rapid rate and begin to answer much more ambitious questions about the formation of new star systems.

You can see the mobie of the data via ths link from the STFC press release.