Picture of the Asteroid Ida and its Moon

By David Dannecker
Senior Editor

On Monday, January 26 this week, Earth had a close call with the asteroid 2004 BL86. Late Monday morning, the asteroid in question passed by our planet at a distance of just 1.2 million kilometers. That’s only three times further from the Earth than the Moon’s orbit, and plenty close enough for the asteroid to be seen through an average telescope. This particular asteroid is about 300 meters in diameter and has a small moon of its own, judged to be between 50 and 100 meters in diameter. No asteroid this big is expected to pass as close to Earth for the next 12 years, so Monday’s event is notable.

Luckily, 2004 BL86 was only passing through the neighborhood, and we avoided an actual impact. But what would the consequences have been if there had been a collision on Monday? And how does this asteroid compare to the other asteroids that populate our solar system?

At 300 meters in diameter, 2004 BL86 pales in comparison to the asteroid that is thought to have been responsible for the K-T mass extinction event that wiped out the dinosaurs. That asteroid is estimated to have been 10 to 12 kilometers in diameter, or at least 33 times further across than Monday’s interloper (and significantly more massive, as volume scales faster than length). Collisions with asteroids on that scale are far more likely to cause mass extinctions, since the impacts are so powerful as to have global consequences. The roughly 10 kilometer asteroid left behind a crater 100 kilometers in diameter and scattered iridium-rich sediment around the globe. Earth would not have been at risk of repercussions on that scale if 2004 BL86 had collided on Monday. Asteroids larger than 10 kilometers are not actually that common in the solar system; out of the tens of millions of asteroids that orbit the Sun, only about 12,000 are larger than 10 kilometers in diameter, and astronomers believe we have identified 94 percent of the asteroids at that scale.

2004 BL86 falls into a category of more average asteroids that are a few hundred meters in diameter. This category includes many of the millions of asteroids that have been discovered, and likely many more that have yet to be noticed. What effects might a collision with an asteroid of this scale produce? While not causing the widespread devastation of larger asteroids, according to National Geographic, asteroids of this middle size would still be fairly catastrophic, devastating whatever region they impacted and potentially destroying entire nations. Given that assessment, we should consider 2004 BL86’s flyby extremely fortunate. Even more fortunate, collisions of that scale are only believed to occur once every half a million years. In addition to these average-sized asteroids, there are millions and millions of smaller, harder-to-detect asteroids that are in the range a few meters to a few dozen meters, only the largest of which would avoid burning up in the atmosphere. Many readers might recall the meteor that exploded over Russia in 2013; that object was about 18 meters in diameter, and while it didn’t impact the Earth’s surface, the explosion was enough to cause over a thousand injuries.

But what are asteroids doing in Earth’s neighborhood anyway? It is true that the highest concentration of asteroids is found in the main asteroid belt that lies between the orbits of Mars and Jupiter. These asteroids would likely have coalesced into a planet in that orbital region long ago, were it not for Jupiter’s immense gravitational influence. Besides the belt asteroids however, there are other asteroids whose regular orbits are dispersed throughout the solar system. A belt of asteroids known as Near Earth Asteroids (NEAs) exists in the vicinity of Earth’s orbit. This belt consists of approximately 12,000 asteroids one meter or larger, of which fewer than 1,000 are larger than one kilometer in diameter. These asteroids tend to orbit for a few million years before colliding with the Sun, colliding with a planet, or being slingshotted out of the solar system altogether. Given that NEAs have such a short lifespan, it’s generally believed that a gradual, but constant, supply of asteroids is nudged out of the main asteroid belt by way of gravitational interactions with Jupiter. So as it turns out, Jupiter’s orbital dynamics are responsible for both the main asteroid belt, and our own smaller belt of NEAs.

Despite the apparently constant stream of NEAs being thrown Earth’s way, astronomers are fairly sure of the low probability of a significant impact. Large extraterrestrial objects are searched for, identified and tracked long before they cross paths with Earth, so the general wisdom suggests we would know a collision was coming long before its arrival; “Armageddon”-style scenarios, where Texas-sized asteroids are noticed with only 18 days to prepare, are incredibly unlikely (especially considering there is literally only one asteroid that large in the entire solar system, and we know where it is). As mentioned, 2004 BL86’s passage is the closest call we’ll have until 2027, when the asteroid 1999 AN10 will pass by Earth on schedule. So humanity can rest easy this week, and probably every week, since astronomers are constantly scanning to find asteroids before they find us. Newer and better telescopes are being constructed. Events like 2004 BL86’s passing give astronomers the chance to observe asteroids up close to learn more about their behavior, and new technologies may aid in the search even further. But with millions of asteroids out there, thank goodness humans have a fascination with watching the skies.


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 photo wherescienceandpolicymeet_zpsb68b5864.jpg

By Melanie Emr
Staff Writer

The United Nations Framework Convention on Climate Change is an international environmental treaty negotiated between 194 parties. Every year since 1995, the conference congregates as the Conference of the Parties (COP) to assess efforts and progress in addressing climate change. Last November, the city of Warsaw in Poland hosted the 2013 COP. The goals of the COP were to promote sustainable development, stimulate green investments and discuss how to finance environmental protection activities. I sat down with Lauren Linsmayer, a Ph.D. student at the University of California, San Diego’s (UCSD) Scripps Institution of Oceanography. Lauren researches marine biology and plays an active role in the interdisciplinary community at UCSD. Recently, she gave a presentation in front of a panel of seasoned ocean scientists at an event sponsored by the U.N. entitled “Ocean Acidification-the other CO2 Problem.” Her talk on the biological and ecosystem implications of ocean acidification can be found here. I sat down with Lauren to discuss her work. She detailed her unique experience at the COP, gave a political analysis of the COP’s goals and shed further light on her research regarding corals and ocean acidification.

To whom did you present your research? What parties were involved?

I presented at one of ten official U.N.-sponsored events during the COP. My event was the only one that focused on the ocean, specifically on the topic of “Ocean Acidification: The Other CO2 Problem.” The event was full house, standing room only.  While we did not take attendance or record what organizations or delegations the audience members represented, the crowd included a diverse mix of delegates, non-governmental organizations and other observer organizations that represented a vast geographical diversity. During the Q&A after the formal presentations, we received questions from representatives of developed and developing countries around the world. Those from coastal and developing nations especially wanted to hear about ocean acidification’s effect on their coastlines and economies as well as what they can do to adapt.

Could you explain how vital coral reef health is to the world and how greenhouse gases are threatening them?

Coral reefs are both ecologically and economically significant. Not only are reefs beautiful, majestic and awe-inspiring, they also support services that generate an estimated $30 to $375 billion per year globally. These services include reef-based fisheries, tourism, medicine and shoreline protection.  We call coral reefs the rainforests of the sea because they host incredible diversity. While they cover less than one percent of the earth’s surface, they support nearly a quarter of all ocean species, many of which depend on reefs for food and shelter. The role of coral reefs in supporting global fisheries is especially important in developing countries where most people rely on reef fish for protein. Fish is the main protein source for one billion people. Fisheries employ around 10 percent of the world’s population, with 90 percent of those jobs being small-scale.

Even if you don’t live near the coast or have never had fish, coral reefs provide you with other services. A medicine you have taken may have been derived from a sponge found on a reef, or your favorite seafood item may rely on coral reefs to hide from predators or to find food.

The vitality of reefs depends largely on the complex structures and topography created by the hard corals themselves. Corals are small, anemone-like animals with symbiotic algae living in their tissues that harden by secreting calcium carbonate. Corals are generally slow growing; most shallow-water corals grow less than one centimeter annually.  This means it takes hundreds of thousands of years to build reefs as structurally complex as the Great Barrier Reef in Australia. The rate of change in ocean pH and carbonate levels experienced by corals today is much faster than anything experienced in at least the past 55 million and possibly the past 300 millions years, putting the reefs at serious risk.

What does your research suggest as key methods to limiting the effects of climate change on society? Do you believe these methods will be easily adopted in both developed and developing nations?

The only way to slow the rate of ocean acidification is to reduce carbon dioxide emissions. The entry of CO2 into the ocean is the main cause of the rapid rates of ocean acidification we see today. Therefore the only way to prevent further acceleration of this pH trend is to slow the rate of CO2 entering seawater.  There are currently no geoengineering solutions to slow ocean acidification; they all affect atmospheric warming but not acidification. Since plants and algae capture and store CO2 during photosynthesis, scientists have proposed farming macroalgae to sequester CO2 in the ocean and bring up the pH, thus making it more basic. This may have local impacts on reducing acidity levels, but the global implications are unknown.

Why should policy makers representing non-coastal societies at the COP care about ocean acidification?

Policy-makers in non-coastal societies should care about ocean acidification because it threatens a multitude of diverse resources that the ocean provides. Ocean acidification threatens to alter marine ecosystems and food webs by impacting the biology of organisms, which will likely impose major costs to seafood industries.

It’s important to note that ocean acidification works alongside many other man-made stressors of  the ocean. These stressors include rising temperatures, deoxygenation, rising sea levels, pollution, over-fishing and deep-sea mining.  The ocean has been treated like a vast, endless pool of resources for thousands of years. Now, it is time to treat it as the finite resource it is.

My colleague Natasha Gallo spoke about the phenomenon of ocean deoxygenation at the COP. To our knowledge, this was the first time this other highly important impact of climate change was discussed at a COP. Though the ocean provides up to half of the oxygen we breathe, it is losing oxygen. We’re seeing major expansions of hypoxic (low oxygen) mid-water zones around the world.  Since fish are very sensitive to low oxygen, this causes habitat compression for many fish species, which means they have to move to more oxygenated waters or face death.

Over 1,598 NGOs are admitted as observers to the COP. While you were at the COP, did you have an opportunity to interact or begin interesting dialogue with any environmental NGOs?

Working at the oceans booth that Scripps co-hosted with the Plymouth Marine Lab was a great opportunity to meet with people from different environmental NGOs as well as other organizations from around the world. I had an interesting conversation with a strategist from New Zealand working with the Climate Action Network.  He has been trying to push the New Zealand government to step up their efforts to reduce CO2 emissions. After informing him about ocean acidification, he thought about mitigating ocean acidification as a strategy for reducing CO2 emissions. New Zealand has some economically important fisheries that may be threatened by acidification and deoxygenation.  It was exciting to hear this political strategy develop around the science of ocean acidification. This experience made me realize the vast importance of scientists directly engaging with policy-makers and political activists to come up with creative solutions.  This realization was also reinforced when two of my colleagues and I serendipitously met with the Executive Secretary of the UNFCCC, Christiana Figueres.  She was thrilled to hear about our efforts to communicate science at the COP and said that she hopes to see more young scientists engaging with the policy arena. This positive reinforcement from her, along with our own success at the COP, is reason to continue our efforts of bringing young scientists from Scripps and UCSD to future COPs.

How is it different presenting your research to politicians at the COP than it is to scientists? How do you make your case more convincing and comprehensible to a non-scientific public audience? What was, in your opinion, the most difficult part about persuading politicians and their representatives to adopt new measures in their country that would mitigate climate change?

It can be a very daunting and difficult task to speak to policy-makers as scientists. Many scientists don’t even feel that they’re qualified to speak in such policy settings. However after seeing the important role that science can and should play in policy-making at the COP, I am more convinced than ever that these two worlds should intersect more often.

As scientists talking to policy-makers, there is a tendency to want to prescribe policy solutions, when in fact we are only qualified to present compelling scientific evidence that may suggest a policy action.  Recognizing the need for careful messaging and clear communication in policy settings, the Scripps Communications Office offered a free “crash course” in talking to the media and public.  In addition, when we arrived at the COP, we were lucky enough to be taken under the wing of Carol Turley, a senior scientist from the United Kingdom who is an expert communicator and has presented at many COPs.  For her crash course, she had us limit our core messages to three main points. She then walked us down to the press offices in the COP to obtain interviews. Our persistence paid off – we were the only non-press people who actually approached them. After talking to press from around the world, we finally obtained an interview with Reuters, which was then picked up by various online news sources. (A link to the interview can be found here).

Here’s some advice on communicating to policy-makers. You need to use very different strategies when talking to policy makers than when talking to other scientists.  Some strategies we used were being simple, stating our main message first, avoiding scientific jargon and using analogies and stories whenever possible.

Australia adopted a carbon tax in 2012 to limit pollution, but now the country is against it and wants it abolished. What can you say about Australia’s participation in the COP in Poland? What kind of example does it set for what should be done to address climate change?

Australia set a very poor example during the COP.  The Australian government had just transitioned a couple of months before the COP in November, and the new government has shown every intention to dismantle previous efforts to combat climate change. On day two of the COP, the Australian government announced new legislation to repeal the EU carbon cap and trade system (Emissions Trading System), to dismantle the Climate Change Authority (an independent advisory board to the government on climate change), and to dismantle the Climate Energy Finance Corporation (invests in clean energy). The very first item of business in the new Parliament has been to abolish the carbon tax, effective July 1, 2014.  During the rest of the COP, the Australian delegation continued to make it clear that they were not interested in reaching climate change mitigation solutions.  They failed to increase their carbon emissions reduction target, despite pressures from both developing and developed countries.  They also blocked a lot of progress during the Loss and Damage Mechanism (LDM) negotiations. The LDM is designed to give financial aid to developing countries from developed countries to assist in covering costs caused by climate change-related events.  The Australian Government’s resistance to funding the LDM led to a weak outcome for the language of that treaty. All this occurred during the immediate aftermath of the devastating effects of Typhoon Haiyan, which severely affected developing countries.

All of these failures on the part of the Australian government earned them a prestigious award, that of the Colossal Fossil. The environmental NGO Climate Action Network gave out this award to the country that did the least to advance climate change mitigation or adaptation during the [Warsaw] COP.

How will developing nations with limited financial access to resources be able to afford new sustainable technologies such as solar panels and wind turbines?

In 2010, the COP in Cancun established the Green Climate Fund (GCF), which is intended to raise $100 billion per year by 2020 to fund climate adaptation projects in developing countries. However, since its creation, it has remained more symbolic than literal because no funds have been raised yet.

The Green Climate Fund was intended to meet the goals of climate change mitigation set forth by the UNFCCC, including aid to developing countries. Their mission states that they aim towards “providing support to developing countries to limit or reduce their greenhouse gas emissions and to adapt to the impacts of climate change, taking into account the needs of those developing countries particularly vulnerable to the adverse effects of climate change.”

Clearly, there are many challenges in convincing developed countries to give large sums of money to the international community to combat climate change.  There has been some success on the company and non-profit level of increasing capacity in developing countries. We were lucky enough to meet with John Doherty, the Global Development Officer at Earth Networks, whose goal is to offer timely weather information to consumers, governments and enterprises through their WeatherBug brand. John’s role is to help with capacity building in developing countries to allow for prudent severe weather forecasting and warnings.

You have high aspirations of becoming a marine advocate after receiving your Ph.D..  How do you intend to use your experience at the COP to educate the general public about how we as a society can work together to mitigate the effects of climate change?

One of the main goals of going was to bring the COP experience back home in order to give other scientists and the public a sense of what happens at these high level policy meetings. We’re actually doing a public event for the organization in San Diego on March 6th to talk about our experience. Other public interactions include news articles like this one in the San Diego Union Tribune.  We also created a website,, to make the COP experience accessible to the public.

This experience was career altering for me. Attending the COP as a young scientist made me realize the importance of obtaining a marine science Ph.D. and gaining expert-level knowledge for whatever future arena I find myself working in, whether it be policy, academia, media or non-profit work.  Many people can walk around talking about climate change and spewing information but having a Ph.D. shows you are an expert and people are more likely to listen to you and trust you. I was honestly surprised to have been well received as a young, non-Ph.D. scientist at the COP. I had presumed people wouldn’t listen to me because I am still working toward expert-level knowledge. I was surprised by how much I knew and how much people respected my opinion. There is a unique and important role that young scientists and youth in general can play in combating climate change, and this is because we are the future generation. Our voice matters because we will experience the effects of climate change in the future, and it is also our problem to solve. Therefore, I encourage and hope that we can inspire other UCSD students to make their voices heard, because you may just be surprised by who will listen!

Image by DFAT photo library