Search results for hanny's voorwerp

Hunting Voorwerpjes

The discovery of the Voorwerp is definitely still keeping us busy as we’re trying to understand it. To recap what we know: the Voorwerp is a bit of a giant hydrogen cloud next to the galaxy IC 2497. The supermassive black hole at the heart of IC 2497 has been munching on vast quantities of gas and dust and, since black holes are messy eaters, turned the center of IC 2497 into a super-bright quasar. The Voorwerp is a reflection of the light emitted by this quasar. The only hitch is that we don’t see the quasar. While the team at ASTRON has spotted a weak radio source in the heart, that radio source alone is far too little to power the Voorwerp. It’s like trying to light up a whole sports pitch with a single light bulb – what you really need is a floodlight (quasar). We’ve been working hard on the X-ray observations that will give us a final answer whether there’s a quasar clevely hiding in IC 2497, or whether the black hole has somehow abruptly stopped feeding.

In the meantime, what we want to know is if there are more Voorwerps, or if Hanny’s Voorwerp is all we have in the local universe. This turns out to be harder than it sounds because asking a computer to go search a massive data set like Sloan for smudges that have this weird blue-purple-y colour is rather difficult. In fact, the Computer said ‘no.’ Fortunately, we could ask you folks to find weird blue-purpley-y stuff around galaxies because such a vaguely phrased question of a human makes sense. And you found more Voorwerps. Since they’re smaller, we dubbed them Voorwerpjes, or `Little Objects’ in Dutch (I look forward to the day that ‘Objects’ are a class of astronomical objects!).

Bill and his team have been taking a look at all the potential Voorwerpjes that you found and many of them are similar to the Voorwerp in the sense that they are clouds of gas lit up by an accreting black hole. All these clouds, like the Voorwerp, are many tens to hundreds of thousands of light years away from the centers of the galaxies they surround. So like with the Voorwerp and IC 2497, we know for a fact that the black hole was feeding tens to hundreds of thousands of years ago. What we’d like to know is if they are still feeding. If not, then clearly black hole meals can end rather abruptly (10,000 years is nothing to a billion solar mass black hole). If that’s the case, then black hole feeding is stranger and less stable than we previously thought….

To find out, we submitted a proposal, again to our friend XMM-Newton, to take X-ray snapshots of the galaxies with the top Voorwerpjes. Fingers crossed that we get the time.

Comic moments with Hanny's Voorwerp and Galaxy Zoo

Time flies. A week ago, I was still running madly around to make sure everything was ready for a trip to Dragon*Con in Atlanta. FireWire cable, cooler for drinks in room, bag full of snacks, lab coat and Einstein wig to be taken seriously as a scientist, big posters of comic pages, PowerPoints for solo talks – check! What is Dragon*Con, anyway? A long holiday weekend with tens of thousands of people gathered to celebrate science fiction, fantasy, science and space exploration, robot building, costuming from all places and times, in our Universe an those so far only imagined. It has developed a reputation for being organized from the ground up, driven more by what the attendees want to see rather than what production companies wan to show. Therefore, it has fit nicely for Galaxy Zoo to have a presence here for the last several years.

These factors made this the perfect venue to host an event marking the launch of the Hanny’s Voorwerp webcomic. As part of the Space Track programming (one of about 25 simultaneous topics available a the Con), a ballroom at the Atlanta Hilton hotel was booked last Friday night at 10 p.m. At Dragon*Con, this is pretty much prime time, since so many attendees keep either astronomers’ or vampires’ hours. Pamela had the printed comic shipped directly there; much relief was expressed when they arrived with a day to spare.

The event opened with live music by the inimitable George Hrab. Among his selections was the Monty Python Galaxy Song; a later selection had lyrics customized for the occasion. Pamela introduced the proceedings, and asked how many people in the audience had ever classified for the Zoo. I counted 23. In fact, I asked this question for all the science talks I did, including panel discussion on the science of Avatar and Firefly. Every time, there were Zooites listening. You can see some of Pamela’s introduction in video edited by someone from the Skeptics Track here, about 4 minutes into the clip.

I spent a few minutes discussing the discovery and scientific followup of Hanny’s Voorwerp. After that, Hanny appeared on screen, Skyping in from Heerlen (and looking extraordinarily awake and chipper for it being 4 a.m. Saturday). For that connection from my laptop, and the UStream coverage, we have Pamela’s little Verizon wireless gizmo to thank – it made the connection via cell-phone network and turned that into a local wireless network, bailing us out when the hotel network wouldn’t quite do it in that room.

After Hanny’s remarks, we passed out the printed comics to the audience, while George Hrab entertained them again. The comic artists, Elea Braasch and Chris Spangler, were in attendance, and the audience had questions about their work and about how strange it was dealing with scientists. Perhaps not so oddly for this age and this project, this was the first time I actually met them.

Artists and Pamela Gay at webcomic launch

Artists and Pamela Gay at webcomic launch

The event finished off with some of the science programs’ trademark ice cream, made quickly from scratch with the help of liquid nitrogen. We gave away three of the big posters I had brought along as door prizes – I couldn’t bear to part with the fourth, showing Hubble peering past the central black hole in IC 2497, and brought it back for my office. There were also some “door prizes” for UStream viewers, randomly selected.

Meanwhile, for everyone who couldn’t be there, the whole comic can be seen online in several formats here.

"Hanny and the Mystery of the Voorwerp" goes live!

Here we are again, representing Galaxy Zoo at Dragon*Con. This is an enormous gathering of science-fiction and fantasy fans, aficionados of science, gaming, costuming, offbeat music – all packed into downtown Atlanta’s five largest conference hotels, every Labor Day holiday weekend. It’s a huge Con – the number of people here at one time or another during last year’s event was nearly one-quarter of the total number of people who have ever signed up for the Zooniverse projects.

Dragon*Con banner

An earlier post told of our presentations in a citizen-science panel in 2008. This year, we’re more deeply involved in several themes represented by attendees – astronomy, citizen science, writing, art, and comics. I refer, of course, to the (web)comic Hanny and the mystery of the Voorwerp, which will be released at a launch event Friday night. (Data from several satellites, including the Hubble Space Telescope, are involved, so of course we would start it with a launch). This is a public-outreach project funded by NASA, through the Space Telescope Science Institute, telling the story first of Hanny’s discovery of the Voorwerp, and then of the efforts of many of us to find out what it is and what makes it shine. Pamela Gay, who has been part of the Zoo education team for several years and is well known as a pioneer in using electronic “new media” to communicate science, took the leading role in organizing the project.

In true Zoo style, the writing of the script was a collaborative effort, carried out at the CONvergence meeting in Minneapolis. Under the watchful eye of fact-and-fiction author Kelly McCullough, the story took shape with a cast mostly composed of interested volunteers attracted by the opportunity. Things then sped up – we had to make the deadline to get some printed copies for Dragon*Con, the last such big event of the year. In the end, I’m very pleased with the result, both artistically and educationally, Kevin looked at proofs and mentioned being gratified at how many bits of science we smuggled in (more or less) painlessly. The combination of line artits Elea Braasch and colorist Chis Spangler worked beautifully, giving a very impressionistic feel to some of the panels. (It was an unexpected bonus that Elea improved dramatically on my actual hair).

The opening event is at 10 p.m. EDT on Friday, September 3. That’s 0200 UT on the 4th – 3 a.m. UK summer time and 4 a.m. across the Channel. Nonetheless, Hanny plans to Skype in so the crowd can “meet” her live. They have booked the Crystal Ballroom at the Hilton for the event. Oddly enough, this is a prime event time for the Con, where things happen 24 hours each day. (In fact, I head afterwards to one of my nightly Live Astronomy events where I’ll be taking requests for objects to take images of with a telescope in Chile). We’ll start with a short talk on the discovery and scientific interest of the Voorwerp, some background on the webcomic, handing out print copies to people there, Hanny’s remarks, door prizes, and a “dress like a Voorwerp” contest. (I have been too busy to find out what kind of material glows bright green under UV light, which would be just the thing.) For those not able to join us in Atlanta, the event will be videocast via UStream. That link also gets you to a form allowing you to order printed copies shipped anywhere at cost, and downloads of promotional posters and cards. Since it’s a webcomic, you can also read it online here once we’ve started the premiere event.

Live or virtual, please join us, and share in the story…

A Comic Voorwerp

Hanny's Voorwerp Painting

line art: Elea Braasch, color: Chris Spangler

This past Monday, at about 8pm Central (GMT -4), a Voorwerpish webcomic was delivered to Sips Comics for printing. Tuesday morning we got the page proofs, and now, one by one, they are being made into full color reality.

We could say a lot of things right now: We could tell you about playing round robin with the script, digitally passing it from person to person under the guidance of Kelly, sometimes into the wee hours of the night. We could tell you about watching the art come to life; transforming from line drawings to fully rendered pages in the hand of our artists Elea and Chris. We could tell you how many pencil tips were broken, and how many digital files grew so big our computers crawled.

We could talk a lot, but instead, let us invite you to join us for the World Premier and share with you a few images.

You’re Invited to a World Premier

Come meet the artists, hear a brief talk by Bill, and generally revel in the Voorwerp’s awesomeness.

And come dressed as a Voorwerp for a chance to win a prize for best costume!

See you in Atlanta?

Pamela, Hanny, Bill, Kelly, Elea and Chris


From Voorwerp to webcomic – the quest continues

This weekend, we’re trying to make as much progress as we can toward producing the webcomic “Hanny and the Quest of the Voorwerp”, a NASA-supported public-outreach effort. Pamela (AKA starstryder) and Bill are at CONvergence in Minneapolis, Minnesota, meeting with writers and artists. In Galaxy Zoo style, we’ve invited people who want to help write it to get involved at three daily working sessions here (with professional writer Kelly McCullough doing the final editing and organizing), then passed onto the artist and colorist. We’ll swap passages with our views of the proceedings.

You can also follow us on Twitter @hannysvoorwerp

Day 0 & 1 (Bill)
I got an early start yesterday, getting here in time to give a seminar on Hanny’s Voorwerp (and its smaller relatives) to the astronomy department at the University of Minnesota. This is usually a good way to bounce ideas off colleagues that I don’t see all the time.

I thought ahead and arrived at CONvergence today properly attired for our sessions.

We were scheduled in a room used at other times for science demos and kids’ programs; it’s full of  such interesting things as M.C. Escher floor puzzles, tornado demonstrators, and robot parts. Pamela had prepared a set of poster-sized prints for the participants’ reference – a picture gallery, cast of characters, and some of the ground rule for the project. After today’s session these went up on the wall outside the meeting room for further reference (along with one of the small posters advertising the sessions), creating a Voorwerp Wall.

Pamela and the Wall of Voorwerpen

Pamela and the Wall of Voorwerpen

We went over some of the early discovery events with some new prospective writers. Tomorrow we hope to get deeper into the story and how to tell it in the most engaging way that suits such a visual medium. Stay tuned for updates…

Days 0 & 1 (Pamela)

Like Bill, I got here yesterday. It was a 7:10am flight out of St Louis and clear flying via O’Hare to Minneapolis airport (a home of terrible coffee and effective luggage carousels). My trip here is being paid for by the Women Thinking Freely Foundation in association with the Skepchicks, so I’m having a blast bouncing between panels on science, skepticism, podcasting, and the Voorwerp.

One of the traditions of this particular Con is plastering the hotel with posters promoting events, so yesterday did my bit to paper the planet and posted our poster almost everywhere. The reason I saw almost is because I discovered several walls where someone had beat me to the punch – printing our promotional posters and hanging them ahead of time. I don’t know who it was, but if I can find them, I want to give them a giant thank you. It was just awesome to come across voorwerps in the wild.

Voorwerp in the Wild at Convergence 2010

Voorwerp in the Wild at Convergence 2010

Today was  more panels, and the opportunity to meet our writers. The group of us gathered around Bill and my laptops, and in many ways it was story-telling hour as we cast the quest for understanding into comic book form. The telescopes became oracles (who sometimes deigned to give us knowledge, and sometimes rejected our petitions for an audience), and in one moment of brainstorming (not to make it into the comic) we had Comic-Book-Hanny Hanny looking at the Voorwerp and asking “What’s that?” while the Voorwerp looked back asking the same thing of all of us humans looking at it. It’s fun playing with language and ideas, even if we have to sometimes toss out the fun ideas to make sure we tell a true and scientific story. Tomorrow we meet again, at 11am central, and we’ll be twittering as we go.



Our goal is for all the writers to get their work done by a week from today (with a few pages to hopefully take back to our awesome illustrators (Elea Braach & Chris Spangler) by the end of this weekend.

This all feels a bit like running with scissors, but I think if we trip, we’re only in danger of cutting up the stereotype that science is boring.

Day 2 (Bill)

This was a real workday on the project – we attracted a couple of new participants, and got into details of how to depict key events, and thinking about what visual scenes captured important moments. I am especially partial to Stephane Javelle’s discovery of IC2497 back in 1908 visually, using the 75-cm refractor at Nice – which translates in today’s comic vocabulary to a 10-meter hunk of steampunk. We liked the idea that Kevin’s thesis advisor should appear only as a hulking , ominous shadow from an offstage figure, and the notion of a globe with word balloons in 5 places all making excited noises when the email announcing Hubble time came out. It will still be a challenge to tell the reader the important things about spectra while keeping the flow and not bogging down in detail.

This photo shows chief wordsmith Kelly McCullough (left) using the posters to bring a couple of new potential writers up to speed on the story so far.

Kelly McCullough discussing the Voorwerp story

Kelly McCullough discussing the Voorwerp story

Hunting Voorwerpjes from Arizona

We have a team working at Kitt Peak again, this time using a spectrograph to chase down Voorwerpjes. As the Dutch diminutive indicates, these are like Hanny’s Voorwerp, only smaller. They are clouds of gas within galaxies (or out to their edges) which are ionized by a luminous active galactic nucleus. In most of these, unlike Hanny’s Voorwerp, we can see other signs of the active nucleus, but the same considerations of hidden versus faded are important. Zooites have given us a rich new list of potential objects, many from the special object hunt set up by Waveney incorporating database queries done by laihro, and more from reports on the Forum. They often show up as oddly-shaped blue zones on the SDSS images, when strong [O III] emission lies in the SDSS g filter. At some redshifts, they look purple, when Hα enters the i filter.

I’m also working with four summer students from the SARA consortium at our 0.9m telescope, normally operated remotely but this time hands-on. (Last night was the first time I’ve ever operated its camera while in the same building as the telescope). One of these students , Drew, is spending the summer working on Voorwerpjes, and is also working on the spectra. Our first night here was devoted just to training at the SARA telescope.

Kitt Peak vista

Kitt Peak vista

Last night we started at the Kitt Peak 2.1m telescope with a long-slit spectrograph known as GoldCam (for its color). For each galaxy, we’ve used whatever previous data were available – SARA images, processed SDSS data, a few observations by other people – to work out the most informative direction to align the spectrograph slit, which then delivers data all along that line on the sky. To set the orientation, we physically rotate the spectrograph on the back of the telescope, taking care not to snag any of the cables. This made it interesting when there was a failure of the hydraulic platform we usually use to get to the spectrograph – it’s been ladders and flashlights to do this tonight. We have a luxurious span of 7 nights (although they are practically the shortest of the year), so we can plan a pretty extensive study. We needed to concentrate on one spectral region for best sensitivity and spectral resolution, so we are using the blue range (3400-5400 Angstroms). For the redshifts of these galaxies, that lets us measure the strong [O III] emission lines and look for the highly-ionized species He II and [Ne V]. These two species are signposts that the gas is irradiated by the UV- and X-ray-rich spectrum of a quasar or Seyfert nucleus, not a star-forming region. Our first task is to conform that this is the case for many of our candidates. Beyond that, the ratios of the emission lines tell us how dense the gas is in each region, and how strong the ionizing ultraviolet is. That, in turn, suggests whether the nucleus has remained at about the same luminosity over the timespan that its light took to reach these clouds, and whether it is hidden from our view by dense absorbing material. The most exciting cases may the the galaxies that seem to have [O III] clouds but no optical AGN; they could be additional examples of the kind of rapid fading from an active nucleus that we believe went on with IC 2497 and Hanny’s Voorwerp.

One of the galaxies I most wanted to see spectra from is UGC 7342, among the greatest hits of the forum and Voorwerpje hunt. It has roughly symmetric regions of highly ionized gas reaching 45,000 light-years from the nucleus on each side, which the images suggested were probably ionization cones. These are the result of radiation escaping the nucleus only in two conical regions on opposite sides (around a thick obscuring disk). This phenomenon is seen in some other type 2 Seyfert galaxies, and if the cones are pointed in another direction, we don’t expect to see deep into the nucleus directly. These pictures were done with the SARA telescope (as I sat in my den with the cats). From left to right, they show [O III] emission, Hα emission, and the starlight alone as seen in a red filter (which has been removed from the emission-line images).

UGC 7342 emission-line clouds: O++, H-alpha, and starlight alone.

UGC 7342 emission-line clouds: O++, H-alpha, and starlight alone.

We aligned the slit with the long axis of the emitting gas (and just about across the bright star at lower left). This paid off spectacularly. Here’s a first look at a 45-minute exposure from earlier tonight. Wavelength increases from left to right, and the bright streak across the bottom is the foreground star’s spectrum. At the wavelets of such lines as Hβ and [O III], the gas glows across a huge region around the galaxy (extending vertically in this display), lit up by an active nucleus which is partially hidden from our viewpoint.

Two-dimensional spectrum of UGC 7342 showing very extensive ionized gas.

Two-dimensional spectrum of UGC 7342 showing very extensive ionized gas.

This is a chance to mention how we (truth in advertising, mostly Drew over the last couple of weeks) have been using the SDSS images to narrow down the most likely candidates for [O III] clouds and get their exact locations for the spectrum. For objects with very strong emission lines in only one or two SDSS filters, we can use one of the other filters as a guess for what the starlight of the galaxy would look like in one of the emission-line filters. We subtract various amounts of this estimate from the filters with [O III] and Hα, and select the one that isolates the clouds best. It’s not perfect, since stars in different parts of galaxies may have different average colors, but does a pretty good job as a screening tool for these active galaxies.

We want to look not only at the best candidates, but a representative set of all kinds that have turned up. This includes “purple haze” a fairly shapeless glow combining the colors of [O III] and Hα, which we see almost solely around the brilliant nuclei of type 1 Seyfert galaxies. This may be what an ionization cone looks like when we look down its axis.

We’re coordinating what we do with three nights coming up in July using a double spectrograph at the 3-meter Shane telescope of Lick Observatory, being carried out by Vardha Bennert. The telescope is larger and the instrument can get good resolution in blue and red simultaneously, so that it makes sense for us to treat some of what we do now as a screening study which can be followed up next month. (Vardha checked a couple of our candidates during a slow part of the night last December, and confirmed a purple-haze object as genuinely large emission-line clouds. This allayed my concern that these might be artifacts of incomplete registration of the three SDSS filters going into color images).

We’re still going, with six more nights and an encouraging weather forecast…

Voorwerp Web-Comic: Authors meeting at CONvergence

It came from the SDSS: The Voorwerp

It came from the SDSS: The Voorwerp

Have you ever looked at the Voorwerp and said to yourself, “Doesn’t that look like the Swamp Thing?” Or maybe you’ve seen Kermit the Frog dancing, or a maybe you see foliage run amok. There is just something about the Voorwerp that make me, for one, want to anthropomorphize it as a monster, and I’m betting some of you have had the same moment of Pareidolia.

The neat thing about the Voorwerp is it not only looks like the character from a bad monster movie, but it is a real-life monster of a problem that has played a starring role in an intellectual adventure. While astronomy doesn’t normally get turned into summer block buster movies, this story just might make it with a rating of “S: Judged appropriate for people who contribute to science in their spare time.”

Image with me – you go into a movie theatre and hear booming from the speakers: “It came on the 13th; Monday the 13th. And one woman dared to ask ‘What is that stuff?'” Suddenly the camera zooms in on the Voorwerp. Then this imaginary movie trailer has us cutting between action adventure shots of astronomers racing for telescopes (you see a car racing across the desert with domes in the distance), the Swift space telescope  repointing, and Zoo Keepers conferring in solemn tones as they gather around a computer. Bill Keel (played by Martin Sheen?) asks, “Can we get Hubble time?” and someone played by the Hollywood hunk of your choice responds in an overly dramatic tone, “I don’t know, but we have to try – I want answers – and we can handle the truth.”

Ok, so maybe the idea is pure cheese, and no Hollywood director (or college film major) is likely to shoot this flick, but there is still a story here that is worth sharing with the world.

And the STScI agrees with us. They’ve funded the creation of a digitized comic book (a web comic) to tell the story of Hanny’s discovery of the Voorwerp and the scientific adventure all of us have gone on as the truth has been sought in all sorts of wavelengths using a myriad of telescopes.

This comic is being written under the guidance of Kelly McCullough (author of the Ravirn series) by a team of volunteer writers at the CONvergence Con outside of Minneapolis, Minnesota, USA. The writers will work in close collaboration with Bill Keel and many other Zoo Keepers to make sure they get the story completely right.

Want to watch? Want to hang out with Zoo Keepers (list of attendees to come) at a cool event? Then join us in Bloomington, Minnesota, July 1-4, 2010. The event does cost money, unfortunately, and you have to register (My turn to bring the cookies). The cost of registration goes up May 15, so if you’re interested, please register ASAP for lowest prices.

We’ll be releasing the comic at Dragon*Con in the fall. We’d love it if you’d consider coming and being part of the celebration.

We’re going to work to keep you informed about everything that is going on. You can follow along at, and in the webcomic thread on the forums.

Voorwerping, Part 1

I’m working on the Suzaku data that we’ve obtained on IC2497, the galaxy next to Hanny’s Voorwerp. X-rays, especially the really energetic ones that Suzaku is able to detect are probably the best way to probe whether the black hole in a galaxy is actively feeding or not. Shanil Virani and I are currently working on the data reduction and analysis, which is quite challenging. Early indications are that the data will show us some really exciting things, but the problem is that they make us really scratch our heads. It may yet take us quite a while to see if we understand what’s going on and we may have to pick the brains of a theorist or two. So, stay tuned….

Unveiling Hanny's Voorwerp – one step at a time

Among the new data we have now is a set of fabulous images taken late last year from the 3.5m WIYN telescope at Kitt Peak, Arizona. We were using a special rapid-guiding CCD camera, which tracks rapid motion due to the atmosphere or wind shaking the telescope, delivering even sharper images than the telescope normally would on long exposures At the end of a 3-night session observing overlapping galaxies to measure their dust content, I couldn’t help noticing that IC 2497 passed nearly overhead just at the start of morning twilight. The atmosphere had been unusually steady so our images were very good. Steady atmosphere, target straight overhead, fast-guiding camera – there was no way we’d pass up this opportunity. The combination paid off; our images in two of the filters were the sharpest ground-based images I’ve ever gotten from anywhere. I knew the telescope could reach that image quality, but never before had it done so for me. In some parts of the image, close to reference stars, the atmospheric blurring amounts to only four tenths of an arcsecond. (When I was in school, it was the received wisdom that the atmosphere would never allow images this sharp for more than a fraction of a second).
Read More…

Voorwerps everywhere

I’m delighted to announce that the fifth Galaxy Zoo paper – the one that discusses Hanny’s Voorwerp – has now been accepted for publication by Monthly Notices of the Royal Astronomical Society.


It’s somewhat of a relief to say that, as it was way back in August of last year that we first submitted it. The referee was extremely thorough, catching a few stupid mistakes we’d made (as a good referee should) and in correcting these and responding to responses for clarification the paper grew from four pages to thirteen. The basic story is still the one that Bill and I outlined more than a year ago – we think we’re seeing the result of activity associated with the black hole in the nearby galaxy IC2497 which has now ceased.

Along the way, another team of astronomers have published a paper about their radio observations of the Voorwerp; I’ll blog later in the week about how we think the two sets of observations are compatible. Hopefully they’ll do the same, and we can have a discussion in public about what we do – and don’t – agree on. By coincidence, their paper is being published in the journal Astronomy & Astrophysics this week – and their image of the Voorwerp made the front cover of the printed edition. We’ll have an image of that for you as soon as anyone involved can find a printed edition – a rare thing in this internet age.

Update : Paper is now available here.

P.S. For those keeping score, our Voorwerp paper was the 5th to be submitted, but the 6th to be accepted.

Update: The pre-print is available on astro-ph now.