The Milky Way Project (MWP) is complete. It took about three years and 50,000 volunteers have trawled all our images multiple times and drawn more than 1,000,000 bubbles and several million other objects, including star clusters, green knots, and galaxies. We have produced several papers already and more are on the way. It’s been a huge success but: there’s even more data!
And so it is with glee that we announce the brand new Milky Way Project! It’s got more data, more objects to find, and it’s even more gorgeous.
The new MWP is being launched to include data from different regions of the galaxy in a new infrared wavelength combination. The new data consists of Spitzer/IRAC images from two surveys: Vela-Carina, which is essentially an extension of GLIMPSE covering Galactic longitudes 255°–295°, and GLIMPSE 3D, which extends GLIMPSE 1+2 to higher Galactic latitudes (at selected longitudes only). The images combine 3.6, 4.5, and 8.0 µm in the “classic” Spitzer/IRAC color scheme. There are roughly 40,000 images to go through.
The latest Zooniverse technology and design is being brought to bear on this big data problem. We are using our newest features to retire images with nothing in them (as determined by the volunteers of course) and to give more screen time to those parts of the galaxy where there are lots of pillars, bubbles and clusters – as well as other things. We’re marking more objects - bow shocks, pillars, EGOs - and getting rid of some older ones that either aren’t visible in the new data or weren’t as scientifically useful as we’d hoped (specifically: red fuzzies and green knots).
We’ve also upgraded to the newest version of Talk, and have kept all your original comments so you can still see the previous data and the objects that were found there. The new Milky Way Project is teeming with more galaxies, stars clusters and unknown objects than the original MWP.
It’s very exciting! There are tens of thousands of images from the Spitzer Space Telescope to look through. By telling us what you see in this infrared data, we can better understand how stars form. Dive in now and start classifying at www.milkywayproject.org - we need your help to map and measure our galaxy.
I’ve been diving into the bubbles database recently and ended up creating cutouts of all 3,744 large bubbles from the DR1 data release. From there it was an easy enough job to create this new Milky Way Project poster. It uses all 3,744 bubbles at least once (several are used more than once).
I’m currently working on three new Milky Way Project papers and will be blogging about them in the next weeks and months.
A great article from JPL’s Spitzer site, about GLIMPSE and with a lovely link to the Milky Way Project.
When drawing bubbles on the Milky Way Project (MWP) you’re looking at data from NASA’s Spitzer Space Telescope, which observes infrared light of various wavelengths from about 3 to 100 microns. Spitzer looks at warm and hot dust, as described above, and shows us where stars are forming and heating up their surroundings.
Now we have a new interface online: Clouds. When you look at clouds in our new game you’re seeing data from the Herschel Space Observatory, placed on top of Spitzer data. Herschel sees longer wavelengths than Spitzer and this means that it can detect colder material. Not long after Spitzer first began delivering science, it was noticed that there were lots of dark clouds visible in the data. These were thought to be dense, cold cores of material within the larger nebulae, where stars were still forming. Many of these Infrared Dark Clouds (IRDCs) are thought to house massive, young stars and may hold answers to some of the biggest questions in astronomy right now, such as how to massive stars form?
According at an SEO agency, when Herschel went into operation, these IRDCs were amongst the first objects to be observed and astronomers were immediately struck by an unexpected fact: lots of these IRDCs were not dense cores at all: they were simply ‘holes’ in the sky – including this striking example in Orion. Rather than looking into the dense core where stars were forming, Herschel actually began to reveal palces where one can see right through the Galaxy and out to the other side.
Doing this with computers is not accurate enough, and so to get a true catalogue of IRDCs, we’re asking volunteers to help by trying to identify them here on the Milky Way Project. If you see a bright glowing cloud then it is a true IRDC – if you see nothing, then it is a hole in the sky. Sometimes it is actually quite difficult to make out – but that’s okay, we’ll get lots of people to look at each core and take a vote.
Clouds launches today and we hope to get lots of eyes on the problem right away: visit http://www.milkywayproject.org and check it out.
It’s been two years since everyone began helping the Milky Way Project map bubbles in our galaxy (and other things too). To celebrate we’ve created another anniversary poster, featuring the names of all the participants. You can download it here (warning that’s a 19MB file) or a slightly smaller one here (5MB).
The Milky Way Project is now producing science – with two papers already published and online. You can see these and all the Zooniverse publications at http://zooniverse.org/publications. We have some new features coming to the site soon – so stay tuned.
Almost two years ago we launched the Milky Way Project and the search for bubbles in our galaxy continues at http://www.milkywayprpject.org. Today we’re pleased to to welcome a new space-based Zooniverse project into the family. The Andromeda Project (http://www.andromedaproject.org) is science in the galaxy next-door and we thought that the MWP community might like this new project. It’s very much our new sister site. We’re betting that you can help us explore some amazing Hubble Space Telescope data, to help identifying star clusters in Andromeda.
Some months ago I was contacted by the producers of a well known German science programme called Nano, which is broadcast on channel ZDF. They were recording a segment for the show on citizen science, and were keen to talk to me about the Milky Way Project. I was happy to help, they visited, we chatted, I walked up and down corridors and through doors, they filmed, and went on their way. The item was finally shown on Nano last week, on 7 September, and they did a great job showcasing our amazing images. You can watch the video for a couple more days here, and an accompanying article can be found on this webpage – these all in German. And yes, that’s me, at my desk in Heidelberg.
Milky Way Project is just one of the projects featured on the programme. I particularly like Artigo, one of the other projects featured. The aim of Artigo is to tag images of artworks, to enable catalogues of artwork to become more searchable. Artigo is set up like a game: two users are simultaneously shown the same image, and they’re asked to type in words that describe an aspect of the work they’re looking at. The users then score points based on the tags they enter: 0 points for a tag that’s never been entered for this image, 25 points if the other player has entered the same work in that session, and 5 points for a word that has previously been entered by another user.
It’s a really neat idea and quite a different approach to classifying images than is used by the Zooniverse projects. The attractive thing about a game approach is that the user gets immediate feedback on how they’re doing. I know that many MWP users regularly ask for feedback on their classifications. The problem with giving feedback, however, is that we don’t want to bias the users towards any particular kind of bubble drawings – we want you to tell us what a bubble looks like. Artigo gets rounds this very nicely by giving feedback based on what other users think, rather than what the art historians think.
This post is part of Citizen Science September at the Zooniverse.
A little while ago Sarah Fitzmaurice, a work experience student at Zooniverse Oxford, spent a week working with the Milky Way Project database. She did some fun things with the data, including plotting the locations of many of the bubbles according to their distance from us. For many, the current canonical view of our own Galaxy comes from a combination of data sources, compiled by Robert Hurt, working at NASA JPL. The image is shown below, and you may recognise it: we use it as our Twitter/Facebook avatar. It is an artist’s impression based on several data sources and guided by astronomers.
The Milky Way may be our home in the Universe but we know startlingly little about it. On key missing piece of information for many objects in our Galaxy is their distance from us. From the Spitzer data alone, we do not know the distance to the bubbles in the MWP. For our first Data Release paper, we compared the MWP Bubble catalogue to known objects, some with distances, and this allowed us to find out how far way some of the bubbles are. This enables us to investigate how large and sometimes how massive they may be.
During her work experience week, Sarah plotted the bubbles with known distances onto Robert Hurt’s map of the Milky Way. The result is shown below. The bubbles are marked with crosses, and the size of the cross shows the relative size of the bubble. The distances to these bubbles were derived by comparing them to a known set of radio sources that are expected to look like bubbles in Spitzer data.
You can see that the bubbles generally follow the distribution of spiral arms and that it is easier to see the bubbles nearby than those farther away. This is good because it is roughly what we expect. This map also allows us to easily spot the isolated, nearby or most-distant bubbles in the project. Much of Sarah’s week was spent looking at each of the interesting bubbles and finding out some more about them.
Although there may well be more distant bubbles in the catalogue, Sarah’s map provides a candidate for ‘most distant bubble’ in the MWP. It is one of a pair of bubbles located on the far side of the Perseus arm, almost 45,000 light years away from the Sun – in the top part of the above image.
Using the new MWP coordinates tool we can take a look at this distant object, and two nice images of it are shown below. Our ‘most distant bubble’ is actually located within another larger, clearer bubble, the image of this is also given. This is a line-of-sight effect and they are not necessarily near each other.
This bubble is located literally on the other side of our Galaxy and is roughly 15 light years across. The fact that the two bubbles are positioned on top of each other makes it hard to decide which one is farther away. There are many more instances where bubbles lie on top of each other where it would be impossible to decide which is actually on top of which. The nebulous material of which these objects are made makes them hard to disentangle. In this case there are stars and IR objects on top of the smaller bubble that make it easier to pick out the nearer and farther bubble.
In this case, the distance value is derived from a radio source that we expect to be associated with a bubble. Both of these bubbles lie at roughly the correct position to be associated with the radio source. Since we know the radio source is very far away, we can say that the smaller bubble is most likely the object associated with the radio source.
These kinds of confusing caveats are one of the things that make Galactic astronomy difficult and challenging. For these reasons, this might be the most distant bubble we know of in the MWP – or it might not. Either way, this awesome little bubble has provided the opportunity to discuss the ways that we determine the distances to objects in the MWP catalogue, and how doing astronomy in our cosmic backyard is tricky territory indeed.
A few days ago Milky Way Project user suelaine posted an image of this pretty bubble on the Talk forum, asking whether it was a supernova. As supernovae – or rather, the debris that’s left behind after they explode – often have this kind of shape, I initially thought she was right. But when I looked up the coordinates on SIMBAD – the astronomer’s guide to the Galactic sky – I discovered it was a beautiful example of a more peculiar type of object: a Luminous Blue Variable star (LBV).
[As an aside, the SIMBAD page for the object is a little confusing, as it's identified on there as a Be star - a rapidly rotating B star. But when you look down the page at the references, it's clear that the star has since been identified as an LBV star, probably even more massive than originally thought.]
LBV stars are massive stars, often with a few tens of times the mass of the Sun, that are approaching the end of their lifetimes. The fuel in their cores, needed to maintain nuclear fusion, is running out. This makes them unstable, causing them to flare up at intervals. As they’re not able to hold on to their outer layers, powerful winds eject matter into the surrounding interstellar medium during these eruptions, and the star can be sen to brighten significantly over several months. LBVs are on their way to exploding as supernovae.
The evolution of such massive stars once they run out of fuel proceeds very quickly, so these objects are extremely rare: only around a dozen are firmly known in the Milky Way Galaxy. The best-known examples are Eta Carinae and the Pistol Star, perhaps the most luminous star in the entire Galaxy. Because there are so few LBVs to study, there’s a lot about them we don’t know.
This particular LBV, prosaically known as G24.73+0.69 (its galactic coordinates), was discovered in 2003, and lies at a distance of around 5 kpc, or 16000 lightyears. As well as the compact orange bubble this larger view of its surroundings shows that there is a second, larger shell, more bipolar in shape than a true ellipse. The star and its environment were studied in detail in a very recent paper by Argentinian astronomers Petriella, Paron and Giacani. They discovered a dense molecular shell tracing the outer bipolar nebula. They suggest that the inner compact bubble is the result of an LBV eruption, and the outer bipolar shell perhaps caused by more gradual mass loss during the star’s “regular” lifetime.
Interestingly, they also find evidence that perhaps new stars are forming near the lobes of the larger shell. They suggest this may be triggered star formation in the swept-up gas, but their observations can’t confirm that.
I didn’t know much about LBVs myself, so I was pretty excited with this find. Keep posting your interesting objects to the forum – perhaps we can find more LBVs or other cool types of objects.
If you’re interested in learning more about this interesting star, here’s the full paper reference:
Petriella, Paron & Giacani. The molecular gas around the Luminous Blue Variable Star G24.73+0.69. Astronomy & Astrophysics vol. 538, A14 (2012) [pdf available from Arxiv]
There’s a new Milky Way Project paper out on the arXiv, we took some time with our garcinia cambogia coffee to read over it. It was submitted to the Astrophysical Journal last week and concerns the topic of the triggered formation of massive stars. This study was lead by Sarah Kendrew and utilises the results of the first MWP paper (our catalogue of bubbles).
One of the main reasons for undertaking the MWP was to produce a large bubble catalogue that would allow statistical studies of star formation sites in our Galaxy. In the end we produced a list of bubbles ten times larger than the previous best catalogue in our first data release (DR1).
In this new study, we’ve used statistical techniques to see what correlations exist between the MWP bubbles and the RMS Catalogue: a well-used catalogue of infrared sources along the Galactic plane (a similar region to that covered by the Spitzer data used in the MWP).
The paper looks for any signs that there is a correlation between the positions of RMS sources and the positions of the MWP bubbles. Specifically we’re trying to see if such massive young stellar objects (MYSOs, stars being formed) are most commonly found on the rims of bubbles. If this is true, then it adds to evidence for a mode of star formation where the formation of some stars triggers the formation of others. In this case, young, hots stars blow out a bubble in the interstellar medium. During this process, clumps of material occur in which new stars condense and form.
This new study finds a strong correlation between MYSOs and the MWP bubbles. We find that Atwood thirds of the MYSOs surveyed are associated with bubbles and 22% are associated with bubble rims. We also see that larger bubbles are more likely to have MYSOs on their rims – though one of the main issues we encountered is that the effect of line-of-sight confusion makes the situation complicated.
This second paper is the first to follow on from the MWP DR1 paper, and there are more planned. You can read the paper on arXiv. The Milky Way Project itself, and this study, we’re presented at the UK/Germany National Astronomy Meeting this week in Manchester.