Earth is no Longer ‘One of a Kind’

For this special little planet, today has been a very big day.

Although we’ve speculated that planets the size of Earth must exist elsewhere in the cosmos, it wasn’t until one of the co-investigators working with the Kepler Space Telescope said he had statistical evidence that worlds of the approximate size of Earth appear to dominate our Milky Way.

We now know Earth isn’t unique.

Alas, this historic news didn’t come without controversy. It was unofficially broken at a TED conference in Oxford earlier this month and only after a recording of a presentation given by Dimitar Sasselov was posted online did the news get out. What’s more, the announcement only became clear when Sasselov referred to a presentation slide depicting a bar chart with the different sizes of exoplanets discovered by Kepler:

A slide from Dimitar Sasselov's TED presentation.

This slide shows the number of exoplanets discovered up until this month, binned by size. We have Jupiter-like exoplanets, Saturn-like exoplanets and Neptune-like exoplanets, all compared with Earth’s radius.

The heart-stopping moment comes when looking at the bar that represents Earth-like exoplanets (i.e. worlds with a radius of below 2 Earth radii, or “<2 Re"). According to Sasselov, Kepler has detected a lot of Earth-like worlds, so many in fact that they dominate the picture. From what we have here, it would appear that around 140 exoplanets are considered to be like Earth.

“The statistical result is loud and clear,” said Sasselov. “And the statistical result is that planets like our own Earth are out there. Our Milky Way galaxy is rich in these kinds of planets.”

But why the controversy? Isn’t this good news?

It would appear that the Kepler co-investigator chose not to wait until the official press release from NASA. He publicized these groundbreaking results in the U.K. at an event where you had to buy tickets to attend. This isn’t usually the stage you’d expect this kind of discovery to be announced — a move that will undoubtedly upset many.

“What is really annoying is that the Kepler folks were complaining about releasing information since they wanted more time to analyze it before making any announcements,” Keith Cowing, of NASAWatch.com, wrote in a SpaceRef article today. “And then the project’s Co-I goes off and spills the beans before an exclusive audience – offshore. We only find out about it when the video gets quietly posted weeks later.”

This sentiment is understandable. Only last month there was some frustration vented at the Kepler team for holding back data on 400 exoplanet candidates. While this might be standard practice — the discovering team should be allowed some time to publish work on any discoveries they have uncovered — telling the world’s scientists they will have to wait until February 2011 before they can get their hands on this invaluable data was a bridge too far.

In light of this, for a Kepler scientist to then jump the gun and disclose a groundbreaking discovery at an international conference without the backing of an official NASA release seems a little hypocritical.

But there is another argument to put out there: Why should anyone sit on such a profound discovery? Perhaps NASA and the Kepler team should have issued an earlier press release announcing to the world that 140 candidate Earth-like worlds have been detected and that further work will need to be done to confirm.

Ultimately, this controversy is just background noise when compared to what we have learned today. Official confirmation or not, Dimitar Sasselov’s message is clear. Although these detections need to be confirmed (hence why these worlds are referred to as “candidates”), it would appear there is an overwhelming preponderance of exoplanets measuring 2 Earth radii or less.

For me, that fact alone is astonishing — the first scientific evidence that worlds of Earth dimensions are not rare.

Earth is no longer unique.

For more, read my Discovery News article, “Kepler Scientist: ‘Galaxy is Rich in Earth-Like Planets‘”

Did the Cosmos Deliver a Googly? ‘Meteorite’ Lands on Cricket Pitch

While enjoying a cricket county match, two spectators were apparently treated to one of the rarest of cosmic events: a meteorite falling from the sky, landing right in front of them. The “dark” rock, measuring 5 inches wide, broke in two on impact. Amazingly, a piece hit one of the witnesses.

“One piece bounced up and hit me in the chest and the other ended up against the boundary board,” said Jan Marszel. “It came across at quite a speed – if it had hit me full on it could have been very interesting.”

It’s not clear from the Telegraph‘s minimally skeptical article when this happened (I’m assuming it was during the recent Middlesex vs. Sussex game in Uxbridge, northwest London, using the tidbits of information from the text) and the only expert opinion cited is that of Dr. Matthew Genge, a meteorite expert at Imperial College, who hasn’t handled the evidence yet.

“If this turns out to be a meteorite it’s very exciting and would be the first fall in the UK since 1992,” Genge points out.

(That last statement isn’t very accurate. I’m certain that there have been many meteorites falling onto the UK since 1992. If proven true, this would be the first witnessed fall in the UK since 1992.)

UPDATE (July 27, 10:22 am PT): With thanks to Philip Stobbart, who also commented on the Uxbridge object, some clarification of Genge’s quote has been provided, I stand corrected:

Ian O’Neill does a good job of debunking this, with one minor error. A ‘fall’ to a meteor expert is one of two categories of meteorites, falls and finds, referring to when they were seen – falling, or found later – not to meteorites actually physically falling. The papers made the same error, although they accepted the idea of this being the first fallen meteorite since 1992…

Original post continues:

Thank goodness the eyewitness account didn’t include a description about smoke bellowing from an incendiary-like pebble (i.e. the recent Israel spoof/weapon), but there are some huge question marks hanging over the validity of the Uxbridge object.

The first red flag is that one of the witnesses said: “…out of a blue sky, we saw this small dark object hurtling towards us.” I might be wrong, but spotting a 5-inch wide object flying through the air, at speed, ain’t easy. I would have thought the only time they were alerted of the ‘meteorite’ would have been when it hit the ground. Or when it hit Marszel in the thorax.

Secondly, was the ‘meteorite’ really 5 inches wide? After a quick search, I found a photograph of the offending object:

5 inches? Are you sure? I know us guys are known for overcompensating, but this is ridiculous. Granted, it’s probably just shoddy reporting, but that piece of rock is barely an inch wide.

Also, when a meteoroid blasts through the Earth’s atmosphere, a huge amount of heat is generated around it, creating a ‘fusion crust.’ This crust should be very obvious surrounding recently fallen meteorites. Looking at this picture, no fusion crust is visible. It could be that we are looking at the interior of the broken ‘meteorite,’ and the black fusion crust is on the other side, but there’s no indication in the photo that this is a bona fide space rock.

If I were to place a bet, I’d say that this is not a meteorite. However, it will be interesting to see what the experts think once they are able to study the sample.

Special thanks to Twitter buddy Madge Leebman for the tip!

Strasbourg July Lightning

A bolt of lightning strikes over Strasbourg, France (Ian O'Neill)
A bolt of lightning strikes over Strasbourg, France (Ian O'Neill)

As you may have noticed, things have been rather quiet on Astroengine of late. This is partly due to my pan-European trek and my work on Discovery News, but mainly due to my horrid affliction of procrastination. Hence why I’m late in posting this pretty awesome picture of a lightning bolt blasting across the French skies.

What was I doing in France? Well, I was asked to do a lecture all about asteroid mining and space commercialization at this year’s Space Studies Program 2010 (SSP10) at the International Space University (ISU) in Strasbourg earlier this month.

It was an incredible experience and I got to meet some incredible people. Hoping to get a blog post up about the whole thing some time over the coming days, but for now, I’ll leave you with this picture of the storm that hit Strasbourg while I was there. For the full set, check out my Posterous gallery.

Hayabusa Re-Entry Video: Spacecraft Destruction at its Best

There’s not a lot to add to this video, it’s too awesome.

It was captured by NASA’s converted DC-8 jet that was flying over Australia when the Japanese Hayabusa spacecraft broke up during re-entry. I’ll let the video do the rest of the talking:

Oh yes, and that little dot ahead of the falling debris? That’s the sample return capsule before it was found int he Outback safely. Thank goodness its parachute worked (presumably).

For more spacecraft demolition awesomeness, read “NASA Aircraft Videos Hayabusa Re-Entry“

Hayabusa Returns to Earth with a Flash

Hayabusa re-enters over the Australian Outback, generating a bright fireball (screen grabs from the JAXA video feed)

Staring hard at the live streaming video of the black Australian skies, I was hoping to see a faint streak of light glide across the camera’s field of view.

But no, it wasn’t that subtle.

Shortly after 9:51 am EDT on Sunday morning (or, for me, a far more civilized 2:51 pm GMT), the Japanese space agency’s (JAXA) Hayabusa’s mission officially came to an end, burning up in the atmosphere. However, a few hours before, the spacecraft released a 40 cm-wide capsule, sending it ahead of the main spacecraft. This sample return capsule would have a very different re-entry than its mothership.

As I watched the small dot of light on the horizon of the streaming video getting brighter and brighter — feverishly hitting the PRTSC button and using some rapid cut&paste-fu in Photoshop — suddenly it erupted, shedding light on the distant clouds that had been invisible in the night.

Far from the re-entry being a faint or dull event, it was dazzling (as seen in the screen grabs to the right).

So, after seven dramatic years in space, the Hayabusa mission has come to an end.

For the full story about how Hayabusa got hit by the largest solar flare in history, limped to visit an asteroid called Itokawa and how its sample-collecting kit malfunctioned, have a read of my main article on Discovery News: Hayabusa Generates Re-Entry Fireball Over Australia

Note: Thanks to everyone who re-tweeted the sequence of re-entry pics. As of this moment it has received over 30,000 views on Twitpic!

Jupiter Got Smacked, Again

Quite frankly, I’m stunned.

An Australian amateur astronomer has just observed his second ‘once-in-a-lifetime’ event: an impact in the atmosphere of Jupiter. Phil Plait was very quick to get the news out, describing it as a “major coincidence,” and he ain’t wrong!

Anthony Wesley’s first event was the famous July 2009 observation of what was thought to have been the immediate aftermath of a comet impact in the Jovian atmosphere. His second happened on Thursday at 20:31 UTC when he was observing Jupiter when something hit the atmosphere, generating a huge fireball.

It is not known whether this event was caused by a comet or asteroid, but in a bizarre case of serendipity, earlier on Thursday Hubble released more information on his original impact event. The July 2009 “bruise” in the gas giant’s atmosphere is now thought to have been caused by an asteroid, and not a comet.

The Hubble press release included details on how researchers deduced that it was actually more likely that a 500 meter-wide asteroid hit Jupiter in 2009. One clue was that newly installed cameras on the space telescope detected little dust in the halo surrounding the impact site — a characteristic that was detected after the impact of the shards of comet Shoemaker-Levy 9 in July 1994. Also, the calculated trajectory of the 2009 event indicated the object didn’t have an orbit commonly associated with comets. If the 2009 event was an asteroid, that means Wesley saw something never seen before: the site of a recent asteroid impact on a celestial body.

And now, less than a year after being the first to see that impact aftermath, Wesley has done it again. Another amateur astronomer, Christopher Go, was quick to confirm Thursday’s fireball with a video of the 2 second flash in Jupiter’s upper atmosphere.

These impact events serve as a reminder about Jupiter’s fortuitous role in our Solar System. As the gas giant is so massive, its gravitational pull has a huge influence over the outer planets, dwarf planets, comets and asteroids. Acting like an interplanetary ‘vacuum cleaner’ Jupiter can block potentially disastrous chunks of stuff from taking a dive into the inner Solar System. It is thought that this distant planet has helped Earth become the thriving world it is today, preventing many asteroids and comets from ruining our evolution.

Thank you Jupiter!

Awesome.

The Moon, Space Shuttle Atlantis, an aurora plus Kibo, all in one breathtaking scene (Soichi Noguchi)

The instant I saw this photograph I realized I was seeing something so beautiful, I’d have a hard job writing something to accompany it.

Coming straight from the Twitter feed of Soichi Noguchi, Japanese astronaut and social-media-in-space-photography-guru, this single photograph has captured the moon, an aurora hanging above the Earth’s limb, a docked space shuttle Atlantis and the International Space Station’s Kibo module (plus a bonus robotic arm and solar panel).

This picture is awesome on so many levels. And to be honest, this should be the photograph of Atlantis’ final mission. It encapsulates so much; a testament to what mankind is capable of and a tribute to the men and women who are currently in space, risking their lives for the advancement of our race.

There’s not much else to say, except: wow.

Black Holes, Aurorae and the Event Horizon Telescope

My impression as to how a black hole 'aurora' might look like near an event horizon (Ian O'Neill/Discovery News)

Usually, aurorae happen when the solar wind blasts the Earth’s atmosphere. However, black holes may also have a shot at producing their very own northern lights. What’s more, we might even be able to observe this light display in the future.

Accretion Disks and Magnetic Fields

Simulating a rapidly spinning black hole, two researchers from Japan modeled an accretion disk spinning with it.

Inside this disk would be superheated plasma and as it rotates it might act like a dynamo, charged particles generating a magnetic field looping through the disk. But this magnetic field wont stay confined to the disk for long. Due to inertial effects, the magnetic field would be dragged into the event horizon, causing the magnetic fieldlines to ‘attach’ themselves to the black hole.

Assuming the accretion disk continues to generate a continuous magnetic field, a global black hole ‘magnetosphere’ would result.

A diagram of the black hole's magnetosphere (Takahashi and Takahashi, 2010)

A Plasma Hosepipe

As you’ve probably seen in the striking imagery coming from the high-definition movies being produced by the Solar Dynamics Observatory, magnetic fieldlines close to the solar surface can fill with solar plasma, creating bright coronal loops. This hot plasma fills the loops, feeding around the magnetic field like a hosepipe filling with water.

The same principal would apply to the black hole’s magnetosphere: the looped magnetic field feeding from the accretion disk to the event horizon filling with plasma as it is sucked out of the disk (by the black hole’s dominating gravitational field).

As you’d expect, the plasma will fall into the black hole at relativistic speeds, converted into pure energy, blasting with intense radiation. However, the Japanese researchers discovered something else that may happen just before the plasma is destroyed by the black hole: it will generate a shock.

As predicted by the model, this shock will form when the plasma exceeds the local Alfven speed. For want of a better analogy, this is like a supersonic jet creating a sonic boom. But in the plasma environment, as the plasma flow hits the shock front, it will rapidly decelerate, dumping energy before continuing to rain down on the event horizon. This energy dump will be converted into heat and radiation.

This fascinating study even goes so far as predicting the configuration of the black hole magnetosphere, indicating that the radiation generated by the shock would form two halos sitting above the north and south ‘poles’ of the black hole. From a distance, these halos would look like aurorae.

Very Large Baseline Interferometry

So there you have it. From a spinning black hole’s accretion disk to shocked plasma, a black hole can have an aurora. The black hole aurora, however, would be generated by shocked plasma, not plasma hitting atmospheric gases (as is the case on Earth).

This all sounds like a fun theoretical idea, but it may also have a practical application in the not-so-distant future.

Last year, I wrote “The Event Horizon Telescope: Are We Close to Imaging a Black Hole?” which investigated the efforts under way in the field of very large baseline interferometry (or “VLBI”) to directly observe the supermassive black hole (Sagittarius A*) living in the center of our galaxy.

In a paper written by Vincent Fish and Sheperd Doeleman at the MIT Haystack Observatory, results from a simulation of several radio telescopes as part of an international VLBI campaign were detailed. The upshot was that the more radio antennae involved in such a campaign, the better the resolution of the observations of the ‘shadow’ of the black hole’s event horizon.

If the black hole’s event horizon could be observed by a VLBI campaign, could its glowing aurorae also be spotted? Possibly.

For more, check out my Discovery News article: “Can a Black Hole Have an ‘Aurora’?” and my Astroengine.com article: “The Event Horizon Telescope: Are We Close to Imaging a Black Hole?“

Was Voyager 2 Hijacked by Aliens? No.

The interstellar probes are still operational (NASA)

The Voyager 2 spacecraft has been speeding through the Solar System since 1977 and it’s seen a lot. Besides scooting past Jupiter, Saturn, Uranus and Neptune, the probe is now passing through the very limit of the heliosphere (called the heliopause) where it has begun to detect a magnetic field beyond the Solar System. The fact we have man-made objects exiting our star system is something that makes me goosebumpily.

For some perspective, Voyager 2 is so far away from Earth that it takes nearly 13 hours for commands sent from Earth to reach the probe.

After decades of travel, the NASA spacecraft continues to relay data back to us, making it one of the most profound and exciting space missions ever launched. Perhaps unsurprisingly, the aging explorer recently experienced a glitch and the data received by NASA was rather garbled.

Naturally, the conspiracy theorists were out in force quickly pointing their sticky fingers at a possible encounter of the 3rd kind. How these ‘aliens’ found the probe in the first place and reprogrammed the transmission for it to appear corrupt Earth-side is beyond me, but according to an ‘expert’ in Germany, aliens (with an aptitude for reprogramming 30 year old Earth hardware, presumably) were obviously to blame.

One of the alien implication articles came from yet another classic ‘science’ post thrown together by the UK’s Telegraph where they decided to take the word of a UFO expert (obviously a viable source) without any kind of counter-argument from a real expert of real science. (But this is the same publication that brought us other classics such as the skull on Mars and the Doomsday Turkey, so it’s not too surprising.)

As I discussed in a recent CRI English radio debate with Beyond Beijing hosts Chris Gelken and Xu Qinduo, the Voyager-alien implication is beyond funny; an entertaining sideline to poke fun at while NASA worked out what actually went wrong. But the big difference was that Chris and Xu had invited Seth Shostak (from the SETI Institute) and Douglas C. Lin (from the Kavli Institute for Astronomy and Astrophysics at Peking University) to join the fun. No UFO expert in sight, so the discussion was biased toward science and logic, not crazy talk.

(It was an awesome show by the way, and you can check out the recording via my Discovery News article.)

So what did happen to Voyager 2? It turns out that aliens are not required to answer this cosmic mystery.

On Tuesday, NASA announced that Voyager 2 had flipped one of its bits of memory the wrong way. “A value in a single memory location was changed from a 0 to a 1,” said JPL’s Veronia McGregor.

This glitch was thought to occur in the flight data system, which formats information for transmission to Earth. Should something go wonky in its memory allocation, the stuff it transmits can be turned into gibberish.

Although it isn’t known how this single bit was flipped (and we may never know, as Voyager 2 is an awful long way from home), it sounds very much like a cosmic ray event interfering with the onboard electronics. As cosmic rays are highly energetic charged particles, they can penetrate deep into computer systems, causing an error in calculations.

And this situation isn’t without precedent either. Recently, NASA’s Mars Reconnaissance Orbiter (MRO) was hit by a cosmic ray event, causing the onboard computer to switch to “safe mode.” Also, Voyager 2 is beginning to exit the Sun’s outermost sphere of influence, where turbulence and confused magnetic fields rule. If I had to guess, I’d say — statistically-speaking — the probe might have a greater chance of being hit by the most energetic cosmic rays from deep space.

Just because something “mysterious” happens in space doesn’t mean aliens, the Illuminati or some half-baked doomsday phenomenon caused it. Before jumping to conclusions it would be nice if certain newspapers and UFO experts alike could look at the most likely explanation before pulling the alien card.

Alas, I suspect that some things will never change.

The Astroengine Universe is Expanding*

Astroengine.com is now being syndicated by The Christian Science Monitor! The CSM has been around for ever (well, since 1908) and it’s a publication that’s won seven Pulitzer Prizes. That’s all kinds of awesome. Personally, I’ve been following CSMonitor.com for some time and their coverage of all things science is excellent — I’m very excited to be a part of their new “Cool Astronomy” section.

But I’m not alone! You’ll find many familiar faces in this new superblog, many of which you can see in Astroengine’s blogroll.

What does this mean for Astroengine? Well, nothing is going to change, except I’ll be less lazy and write more. My plan for Astroengine’s global domination is on track!

*I stole this title from a Chipotle ad, but it’s a great ad (and an awesome Mexican take out), so why not? Unfortunately the burritos aren’t free in the Astroengine Universe.