Ian O'Neill

Star Birth Dominates Energy Production in Ultra-Luminous Galaxies

Artists impression of an ultra-luminous galaxy heating the surrounding dust (JAXA/ISAS/LIRA)

In the early 1980’s, NASA’s Infrared Astronomical Satellite (IRAS) detected a number of unknown objects lurking in the depths of the cosmos.

At the time, these IRAS objects stirred speculation in the press. Were the infrared signals being emitted by comets inside the Solar System? Or were they failed stars (brown dwarfs) lurking beyond the orbit of Pluto? The latter theory spawned the idea that the hunt for Planet X was back on (stoking the smoldering conspiracy embers of the flawed doomsday theory that Nibiru is coming to get us). Alas, it was neither, these intense infrared signals were coming from much, much further away.

It turned out that the infrared emissions were being generated by galaxies that, bizarrely, had little optical signal. Although a high proportion of them were known to be interacting galaxies (i.e. they were colliding with other galaxies), the exact energy mechanism driving their emissions was not known.

Ultra-luminous galaxies have the luminocity of a trillion Suns, whereas our galaxy has the luminosity of a pedestrian ten billion Suns. Obviously, ultra-luminous galaxies are different animals to the Milky Way, but a galaxy is a galaxy and the energy sources are similar whether they are ultra-luminous or not. It would appear that the only difference is how active the galaxy is.

The first obvious energy source in a galaxy is star formation; the more stars that are forming, the brighter the galaxy. Secondly — as with our galaxy — the central supermassive black hole’s accretion rate contributes to the galaxy’s energy budget; the more matter being accreted by the black hole, the more energy is being generated (and therefore the brighter the galaxy).

So, when observing these ultra-luminous galaxies, surely it should be an easy task to work out where all this energy is coming from? Actually, this isn’t the case, astronomers are having a difficult job in understanding the nature of IRAS galaxies and the reason for this comes from the source of the infrared emissions. Galactic dust is being heated by the energy source, but this dust obscures the source of this heating (it is opaque to optical wavelengths).

Smithsonian Astrophysical Observatory (SAO) researcher Guido Risaliti and his team have been analyzing Spitzer data to try to characterize the infrared emissions from 71 ultra-luminous galaxies. Using a “dust emission diagnostic technique,” the team have deduced that approximately 70% of the galaxies have active nuclei (i.e. their supermassive black holes have high accretion rates). Although most of the galactic nuclei are active, it is star formation that dominates the energy production in two-thirds of the galaxies. Also, these account for the highest fraction of the brightest galaxies.

This is a significant finding as it demonstrates how a galaxy reacts when it interacts with another galaxy. It would appear that the black hole in the core of the galactic bulge is kick-started during the massive gravitational interaction, boosting energy output as it eats more matter. The interaction also boosts star birth and this energy source becomes a dominant factor. Both energy sources heat up interstellar dust, making the galaxy glow in infrared wavelengths while optical light is masked.

Source: SAO (Harvard)

The World Needs Sagan-Man [Update]

I love today’s XKCD comic. It depicts Sagan-Man, a superhero who possesses Carl Sagan’s ability to communicate science to the world. In this case Sagan-Man uses his inspirational tone to stop a thief in the act.

Unfortunately, I was too young to experience Carl Sagan when he was in his prime years presenting Cosmos, and it is only comparatively recently that I have been watching recordings of this legendary series. I have since brought the book too.

Sagan captures the child-like wonder of the Universe that is so often missing in the world today, and while there are many outstanding scientists and presenters who fill this roll of outreach, nobody does it quite like he did.

Update: With thanks to @acsnotsettled for the suggestion, perhaps the next Carl Sagan should team up with Buzz Aldrin. That way they can really smack down the crazy conspiracy theorists (i.e. if Sagan can’t convince then the Universe is way cool without UFOs and Bigfoot, Aldrin will beat it into ’em).

Some Doomsday Crazy With That Google Search?

After collecting myself from the bout of giggles when I read The Bloggess’ post about the rather bizarre auto-suggestion in Google Search, I was ready to find some more. (Awesome, the old classic, “french military victories” followed by clicking the “I’m feeling lucky” button is still working.)

But what’s this? @Mactavish shoots me a tweet telling me to check out typing in “why will” to the Google Search box. As innocuous as it may sound, the auto suggestions are not. I mean, why the heck would anyone need the suggestion: “why will a carrot slice when placed in tap water for several hours become very stiff”?

Kidding. Mary isn’t referring to stiff carrots, I think she might be pointing out the sheer amount of doomsday Crazy going on. Wow. Type in “why will” and you get “why will the world end in 2012”? How about typing in “why won’t” and get redirected here.

Sigh.

The Dawn of a New Age for Sci/Tech Reporting

You may have noticed the increased chatter about the quality of sci/tech reporting in recent years. I know I have.

In this age of incredible technological advancements and scientific discovery, it can often be very hard for reporters to root out what is important and what isn’t. Also, with the increasing reach of online media, there’s a massive opportunity for media outlets to communicate science through good science journalism. This is essential, as pseudo-science and bad science reporting is often being communicated faster. Unfortunately, with the continuing cutbacks being made by traditional media sources of their science coverage, disinformation is finding an unprecedented foothold in popular culture, culminating in irrational fears of scientific achievement and scaremongering hype.

But this has created an unprecedented opportunity for a small band of professional correspondents, editors, producers and publishers known as Discovery News.

For the last 11 years, Discovery News has been working hard to report on advancing sci/tech trends as the news body of the Discovery Channel. On Sunday, Discovery News came of age; it was re-launched and re-branded with a new design and URL.

At a time where cutbacks are becoming the norm, it might seem strange to see a new sci/tech news resource appear on the Internet, but we have identified a gap in reporting that needs to be filled urgently. What makes us even more special is the fact we are coming from a TV-based network (rather than the bedraggled press-based news), so we already know how to “do” online media through a variety of platforms.

On the new-look Discovery News, you’ll find the main 3 Discovery topic hubs (Space, Earth and Tech) combined seamlessly with news across 8 key topic areas (from Dinosaurs to History). We have combined the skills of dozens of correspondents, media experts and scientists to ensure that we have an unparalleled coverage of breaking news as well as in-depth analysis. We are also addressing the need for a massive reader-based interaction by incorporating reader comments and connecting with the rapidly growing population of social media users. The site is personality-driven so our readers can interact directly with the people who are producing the news at ground level.

But the best thing is that all of our producers and contributors are professionals in the fields they are reporting on, ensuring a high level of journalistic integrity and knowledgeable opinion.

All in all, this is the most exciting project I have ever been involved with, and I hope you will all join me over on Discovery News to embark on this voyage of discovery.

Now that we have launched, I now have a bit more time to do some more Astroengine posts!

A Bevvy of Doom

On the red carpet: John Cusack tells me what he'll be doing on Dec. 21st, 2012. Skiing (credit: Debra O'Neill/Discovery News)

Currently sitting in the departure lounge in LAX before I fly out to Washington D.C. to meet up with the Discovery News crew ahead of the launch of our brand new site (keep an eye on Discovery Space, it will soon be integrated into the Discovery News redesign — the beta version looks awesome).

Before I fly, I just wanted to post the news that the Discovery Channel will be airing the documentary I was interviewed for by KPI Productions in August. According to my DVR, the show “Surviving 2012” will be showing on Sunday (Nov. 8th). I’m not certain when it will be showing internationally, but in the US it will be on at 9pm PDT — so check your local listings for any slight changes in schedule. I think it’s going to be a great show as science is the focus, not the hype (unlike the idiotic History Channel-esque Nostradamus nonsense). However, I think fellow interviewee Dr. Alex Young and myself arrived at a very interesting conclusion as to the realities of being hit by an aggressive solar storm. Although our conclusions are far from the rip-roaring, solar blowtorch popular in sci-fi, we do point out that solar physics research is horribly underfunded considering our dependence on vulnerable power and communications systems.

In other news, on Tuesday night I attended the 2012 premier red carpet event in Downtown Los Angeles. I met some bloke named John and another called Roland. Apparently they’re quite famous, but what would I know. For more on my A-list adventures, have a read of “What Will John Cusack be Doing on Dec. 21, 2012? Skiing.” and check out some of the photos from the event via my Facebook account.

Spirit Suffers Another Bout of Amnesia. Spirit Suffers Another Bout of Amnesia.

"Oh, that's a nice view, I hadn't noticed that hill before. Hey, that's a pretty-looking rock!"

NASA’s Mars Exploration Rover Spirit is suffering from amnesia, again.

This is hardly surprising if we consider that the lifespan of Spirit should have been 3 months, the fact that it has lasted 69 months (so far) is nothing short of miraculous. In rover-mission-lifetime years, doesn’t that make Spirit and her twin sister Opportunity 1380 years old? (I decided that a “lifetime” is 60 years, in case you were wondering.) Perhaps that’s not how it works, but for NASA to build a robot that has lived 23 times longer than the mission specified is pretty damn impressive. No wonder Spirit is losing her memory. I’m surprised she hasn’t lost the will to live.

Spirit has lost the use of one of her wheels and remains stuck in the sand… so she is showing her age. But still, 23× longer than planned? When I’m 1380 years old, I hope I’m only suffering amnesia every now and again.

Source: Physorg.com

What Will It Take To Blow Up Pluto?

“25 billion of your biggest bombs please. I’ll pay credit, thanks!”

"I love the smell of venting volatiles in the morning..."

The Pluto debate frustrates me, as you may have noticed. It’s not that I have particularly strong views about whether it should be called a planet or a dwarf planet or a plutoid or pygmy planetoid, it’s that I really don’t care; I actually see Pluto’s “demotion” as exciting progress in the field of Solar System science rather than any derogatory gesture aimed at Pluto. Pluto is still Pluto; it hasn’t been knocked out of orbit, it hasn’t even been “bombed” (unlike our poor old Moon), it’s just being filed under a different category.

A King Amongst Dwarfs

In my opinion, calling Pluto a “planet” was unworkable, especially after a bigger dwarf planet was discovered in 2005 by a team of astronomers led by Dr. Mike Brown. This dwarf planet was named Eris (or 136199 Eris) and at first it seemed like we had gained a tenth planet.

The “ten planets” thing was short lived, however. In recognition that Eris probably represented the beginning of a spate of discoveries of welterweight worlds, the International Astronomical Union (IAU) took a vote in 2006 and decided to redefine what constitutes a planet. Pluto was in the firing line, became a rounding error and was dropped from the planetary club.

But it wasn’t all bad for the little guy. Pluto was designated king of all “plutoids” (trans-Neptunian dwarf planets) in 2008, meaning another three dwarf planets now orbited the Sun with this designation (Eris, Haumea, and Makemake in addition to Pluto).

In a previous Astroengine article, I made the point (and I’m going to quote myself because I can):

Just so my opinion is known, I don’t care what Pluto is called. If NASA decided to explode Pluto as part of a Kuiper belt clearing project, then yes, I might be a bit annoyed; I’d even start a blog titled “Save Pluto.” But calling Pluto a dwarf planet (or the rather cute plutino) really doesn’t bother me.

I haven’t really thought much about this statement until, today, @PlutoKiller himself (Mike Brown) tweeted, “Seriously, what just happened? The entire discussion is on placing explosives in the solar system. Pluto has not even been mentioned.” I then fired off a reply saying something about building a New Horizons 2 and packing it with plutonium to which @PlutoKiller said, Evil Santa-style: “Just in time for Xmas.”

And then the penny dropped.

Kuiper Belt Cruelness

To be honest, I’m astonished I haven’t thought of this before. Looking at Mike’s Twitter feed should have been enough inspiration, but until I wondered down the bombing Pluto => plutonium enrichment => lets fly a shedload of plutonium to Pluto path, that I asked the question: How much energy is needed to completely destroy Pluto?

Now we’re talking! Time for some Kuiper belt mayhem!

I’m not talking about simply bombing Pluto and making a big crater, I’m not even talking about fire bombing all the volatiles out of its frozen surface, I want to remove Pluto from existence. Why do I want to do this? Well, for fun, and because @PlutoKiller himself said so. And it’s Halloween, so why not?

So how much energy is required to do this?

For this gargantuan task, I cheated and looked up the method used by Matt Springer over at Built on Facts to derive how much energy was required by the Star Wars Death Star to shred Earth. In that case, 2.2 × 10³² Joules was needed to totally erase our planet (that’s a week’s-worth of solar output). That’s a lot, right?

Plutoid Killing Equation

Now, energy is energy and mass is mass, let’s give Pluto the same treatment. Using the following equation (known henceforth as the “Plutoid Killing Equation”, or simply PluKE), we can find out how much energy we need to erase Pluto:

The equation that can turn a dwarf planet into dust, as derived by Matt Springer.

This equation is the total gravitational binding energy of a sphere of mass, M and radius, R. G is the Gravitational Constant. For Pluto, a sphere, its vital statistics are:

M_Pluto = 1.305 × 10²² kg

R_Pluto = 1.153 × 10⁶ m

and

G = 6.673 × 10^-11 m³ kg^-1 s^-2

Plugging the numbers into PluKE, we can derive the total energy required to kill Pluto, literally:

E_Pluto(dead) = 5.914×10²⁷ Joules

But what does this number mean? This is the bare minimum energy required to match the gravitational binding energy of Pluto. If you want to rip the dwarf planet apart (plus pyrotechnics and speeding debris), you’ll need a lot more energy. However, nearly 6×10²⁷ Joules (that’s a 6 followed by 27 zeros) delivered into Pluto in one second should give the little world a very bad day.

Tsar Very Much

But how can we “deliver” this vast quantity of energy in one second? I suspect that any super-advanced civilization hell-bent of wiping out planets will have a better idea of this than me, but using weapons that are available to modern man might be a good place to start. Forget the uber-powerful death ray emitted by the Death Star, that’s sci-fi. It may not be sci-fact, but how about sending some nuclear bombs to the Kuiper belt?

How many bombs will we need? Ten? Ten dozen? A thousand?

The most powerful nuclear weapon tested was the Soviet 58 MT Tsar Bomba in 1961. So if we know how much energy is released by one of those beasts, we should be able to work out how many we’ll need to send to the unsuspecting Pluto.

1 MT = 1 megaton of TNT = 4.184×10¹⁵ Joules

therefore, a single Tsar Bomba has the potential to release an energy of:

58 MT = 58 × 4.184×10¹⁵ Joules = 2.427×10¹⁷ Joules

We needed 6×10²⁷ Joules to wipe out Pluto, obviously the 2.4×10¹⁷ Joules a single bomb can deliver is woefully short of our goal. So how many Tsar Bomba weapons do we need?

(6×10²⁷ Joules) / (2.4×10¹⁷ Joules) = 2.5×10¹⁰

We need to build 25,000,000,000 nuclear bombs. 25 billion. Ouch.

Obviously, looking at this estimation, it is impossible to destroy a dwarf planet as puny as Pluto using the most powerful weapon known to man. Also, it’s worth keeping in mind that this is the bare minimum of energy that needs to be applied to Pluto to match its gravitational binding energy, so to destroy it, you’ll need a lot more bombs.

There’s also the question of how to distribute the weapons. Would you put them all in one place? Distribute them all around the globe? Perhaps burrow into the centre of the body? I suppose putting all the bombs in one place might be impressive, kicking a chunk of plutoid into space.

Now I must report these findings to @PlutoKiller himself, I fear he won’t be happy with the outcome of my calculations…

NASA, Ur Doin’ It Wrong

Although I’ve been neck-deep in Ares I-X launch news today, I’ve had some time to see what else has been going on in the Universe. I really hope I’ll find the time to get to this stack of blog post ideas over the weekend, one of them is a particular peach.

But before I turn in for the night, an interesting little debate has been sparked over at Keith Cowing’s NASA Watch. Keith, the ever watchful eye over all things NASA, somehow stumbled across the NASA 360 blog and pointed out that the agency might be trying too hard to be “hip.”

I think that one of the hardest things NASA has to do is to communicate their incredible science to the general public — no one said outreach was easy. Every day I am challenged with this issue on Discovery News. On the one hand I want to talk about the quantum effects of Hawking Radiation at the event horizon of a black hole, but on the other, I have to realize that most of my audience didn’t take Advanced Quantum Mechanics at school.

Realizing how to approach an audience with science is a bit like approaching a crème brûlée with a blowtorch; you have to do it slowly, with enough distance between the caramelizing sugar (audience) and the flame (science). You get too close and the mix gets burned (confused), get too far away and the mix is undercooked (bored).

This by no means is equivalent to “dumbing down,” it’s simply a method to find analogies and examples that can connect the mind-bending science with a tangible reality (like comparing the curvature of space-time with the curvature of a rubber sheet when a heavy ball is placed on top of it). If you start over-simplifying the science, you end up sounding like a tool and your audience thinks you’re lame/boring/condescending.

If analogies and examples aren’t forthcoming, try humour. One example of this is “5 Frightening (But True) Space Stories,” a guest blog post for Space Disco Robert Lamb posted today. Robert is an expert at blending science and humour. So much so, this blog post teaches some spaceflight history without you even realizing it.

So, back to NASA Watch and the comments about the NASA 360 blog post written by presenter Jonny Alonso:

I am certainly all for trying to connect to a broader audience but this NASA 360 post by Johnny Alonso (the MTVish on-air host) is just silly with its attempt at teen Twitter and SMS lingo i.e. “hai guyz” and “that would totally suck. lol”, “it was hawt :)” and “These cats Mike and Barry”. –Keith Cowing, NASA Watch

Running the risk of sounding a little long in the tooth, Keith is obviously a little riled about the standard of writing on this particular post. At first, I was mildly amused, but the more I looked at it, the more I realized NASA’s outreach style might be flawed. Using text-speak to convey his work presenting for NASA makes Alonso sound limited (which I’m sure he’s not, although I haven’t seen him in action, so I might be wrong), but worst of all it knocks the credibility of NASA outreach.

This might be one form of communication, but there must be some kind of editorial control? Are there standards? Granted, I think the content produced by NASA online is second to none, which is probably why NASA 360 is standing out like a sore thumb. Also, this blog post is the personal angle written by an enthusiastic young guy in a conversational, loose tone who probably has a lot of fans.

Perhaps I’m just old fashioned in agreeing with Keith, but “outreach” doesn’t mean NASA should be publishing blogs like this to try to appeal to a younger/trendy audience. As sad as it may be, if the younger generation isn’t interested in NASA, I doubt a presenter saying “hai” all the time is going to change that.

What do you think? Am I being picky? Is this just a symptom of what we can expect from blogs in the future?

Ares I-X Away!

The Prandtl-Glauert singularity forms as Ares I-X goes transonic (NASA)

What’s the cloud surrounding the Ares I-X during its transonic flight? Have a look at my Discovery News Big Pic for the answer…

You could say it’s been an eventful day… but you’d be understating the importance of the last 24 hours. We saw the first test launch of the Constellation Program, and it was a success (despite being delayed by a day). Although it’s going to be a while until NASA processes all the data gathered from the launch, I watched that elegant white rocket take to the skies above Kennedy Space Center and thought “I can see astronauts travelling on that thing.”

Alas, this thought may be fleeting as the Constellation Program is underfunded and lacking direction. However, there’s a lot to be said for seeing the Ares I test vehicle soar 28 miles into the atmosphere. Could this “proof of concept” sway funding decisions in NASA’s favour?

I couldn’t even guess right now.

So, for now, let’s enjoy the Ares I-X launch and congratulate NASA on a job well done. The US space agency has done mankind proud. Again.

Forget 2012, THIS Is What The Mayans Should Be Remembered For

maya-pyramid

Forget the supposed “Mayan Prophecy” of doomsday in 2012, the Mayan civilization never (ever!) predicted that the world was going to end on Dec. 21st 2012. Really, no ancient Maya elder ever said anything about doom. Also, no Mayan descendent believes that their ancestors foretold doom (and in fact, they’re getting rather pissed off at the insinuation).

Are you seeing a pattern yet? Please say you are.

In short, the world isn’t going to end in 2012, it is simply the end date of the Mayan calendar. There is nothing scary, spooky, weird or ominous about that despite what the doomsayers keep telling us. As I talked about in a previous article, 21/12/2012 is going to be a poignant reminder that the Mayan Long Count calendar represents the last breath of an ancient civilization.

And to be honest, who needs doomsday theories when the history of the Mayan culture is so fascinating anyway. I’m totally blown away by this video:

I’ve already received a message indicating this CNN news article is somehow a coincidence and therefore proof of some kind of “shift.” (I’m assuming we’re taking about a shift of a “New Age-conciousness” kind and not of a “Oh crap, the magnetic poles of Earth just went ass-over-tit for no apparent reason” kind.)

However, the timing of this news report is no coincidence. Can you guess why?

Hint: in about three weeks time, a fun little movie called 2012 is going to be released. It might have a terrible plot, it might even be over-hyped, but I wager that the 2012 movie will be a blockbuster. Blockbusters = audience. So, why do you think this mother of all coincidences just happened? Why would CNN decide to run this news report now? Do you think it might be the same reason why every media outlet will be pulling apart every aspect of 2012 for most of November?

Wow, I am getting cynical.

Special thanks to @Aife_Earthstone for the link to this video!