NASA probe MESSENGER is first to enter Mercury’s orbit

Posted on March 18, 2011 by | 1 comment

Humanity has just reached another milestone in space exploration. Yesterday, on March 17, NASA’s MESSENGER probe entered orbit around Mercury becoming the first spacecraft to ever do so.

MESSENGER probe approaching orbit around Mercury

MESSENGER (actually short for Mercury Surface, Space Environment, Geochemistry and Ranging) was launched almost 7 years ago in August of 2004. It was designed to examine the magnetic field around mercury, as well as chemical composition and geology of the surface.

Since then, MESSENGER has made three flybys past Mercury and has made some interesting discoveries that have puzzled scientists for years.

Evidence of Volcanic activity on the surface of Mercury

Back in July of 2008, MESSENGER made the startling discovery of water present in Mercury’s exosphere (the uppermost later of the atmosphere). It also found evidence of extensive volcanic activity on Mercury’s surface. Previously, scientists believed that the volcanic gases would have long ago exited Mercury or had been absent at its formation.

MESSENGER’s new mission will have it begin to throughly examine the surface for the chemical signatures of these gases with an array of seven instruments (set to be activated on March 24). The probe will also study the presence of water on Mercury and also examine the planet’s core.

MESSENGER's gravity assist maneuvers

What made MESSENGER’s voyage to Mercury interesting were some of the challenges that scientists had to overcome. Normally, a probe approaching the planet would become too accelerated due to the force of the Sun’s gravity and fly past the planet before it could maintain orbit. MESSENGER had to overcome this by using a series of gravity assist maneuvers to slow it down. These maneuvers utilize the gravity of a planet to change the path of the spacecraft. If you’ve ever seen the movie “Armageddon”, this was like the scene where the spaceship did the “roadrunner thrust move” around the Moon. MESSENGER had to utilize the gravity from Mercury, Venus and Earth to perfect its trajectory to orbit the planet.

What’s truly remarkable is that these series of gravity assisted moves mean that MESSENGER has traveled 7.9 billion kilometers through space since 2004.

The other challenge for scientists was thermal damage due to Mercury’s high surface temperatures. They solved this by making MESSENGER have a highly elliptical orbit around the planet. The trajectory takes the probe within 200 km of the surface then 15,000 km away, presumably when the temperatures are hottest. One of these cycles takes 12 hours.

The probe’s first set of measurements are scheduled to be sent to Earth on April 4. Who knows what’s waiting to be discovered beneath the surface of Mercury!

The original article can be found here.

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The Gulf of Mexico Still Far From Recovery

Posted on March 18, 2011 by | Comments Off on The Gulf of Mexico Still Far From Recovery

A video of the BP Spill Explained: YouTube Preview Image

The Gulf of Mexico Oil Spill, also known as the BP Spill occurred on April 20, 2010 is known as the largest accidental marine oil spill in history[1]. The cleanup was done by burning the oil, and using chemical dispersant as well as oil-eating microbes. Microbes are small unicellular organisms. Alcanivorax borkumensis use oil as food[2]. By August 2010, most of the oil on the surface of the ocean was dissipated[3], but about 79% of the oil was still under the surface[4]. The BP (British Petroleum) compensation czar claimed that the Gulf would be recovered by 2012, however, research conducted by marine biologist Dr. Joye demonstrated that the oil is not degrading fast enough[5].

Joye’s research included 5 expeditions using deep-dives into the Gulf of Mexico near the oil spill to collect 250 samples from the ocean-floor and water columns. Her study found that much of the oil spill on the ocean floor and the water columns were from the BP spill. This was done by chemically fingerprinting the oil, and testing the samples in labs.

According to Joye’s findings, the oil-eating microbes that were thought to degrade most of the oil spill consumed about 10% of the oil spill. The rest are dispersed throughout the Gulf as small droplets, which can’t be seen on the surface, but a large amount of the oil droplets sank to the ocean-floor. Moreover, the mucous secretion from the oil-eating microbes which also contain oil sank to the bottom, on top of many bottom-dwelling sea creatures, such as starfish and crabs. Joye’s estimate of the total amount of oil leaked into the ocean is equivalent to 1.5 and 3 million barrels, and she thinks that the recovery will be much slower than what the BP czar claimed.

Oil on Floor

A wall of methane ice on the bottom of the Gulf of Mexico - Woods Hole Oceanographic Institution

The damage done by this accident propose a much long-term effect on the fragile marine ecosystem as well as the marsh in Louisiana. Before reading about Joye’s research, I used to believe that the oil spill was recovering fast, mostly by the oil-munching microbes. However, the pictures and the data collected from the bottom of the ocean by Joye changed my opinion, that under the turquoise-blue surface of the ocean, the sea-floor is still struggling to recover.

The long-term public health implications from this spill is unknown, and still needs to be studied.

An Interview with Dr. Samantha Joye at the UGA Oil Spill Symposium on 26th of January 2011:

YouTube Preview Image

[1] http://en.wikipedia.org/wiki/Deepwater_Horizon_oil_spill

[2] http://www.scientificamerican.com/article.cfm?id=scientists-break-down-oil

[3] http://www.nytimes.com/2010/07/28/us/28spill.html?_r=2&hp

[4] http://www.bloomberg.com/news/2010-08-17/scientists-say-79-of-spilled-oil-may-remain-challenging-administration.html

[5] http://ca.news.yahoo.com/gulf-mexico-bottom-shows-little-sign-recovery-bp-20110219-152454-973.html

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Posted in Environment, Science Communication, Science in the News

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Nuclear crisis in Japan

Posted on March 18, 2011 by | 2 comments

In wake of the 9.0 magnitude earthquake and tsunami which struck Japan on March 11, there have been 6,911 deaths, 2,409 injured, and 10,692 people missing (Wikipedia, visited on March 18th 2011) as well as immense property damage. However, these figures will pale in comparison to the casualities that could result if Japan does not act now to prevent the looming disaster it is now facing. Due to the tsunami flooding backup power stations, six nuclear reactors of the Fukushima power plant had malfunctioning cooling systems, threatening a nuclear meltdown. Should the reactors leak out its radioactive fuel before they have cooled down, radiation levels in the atmosphere may become lethal to residents and possibly a global health threat.

The radiation leaking out of the reactors poses a health risk. The strong radiation emitted from nuclear reactions are able to ionize atoms by knocking electrons out of their orbitals. Nuclear radiation becomes a problem for humans if DNA molecules become ionized by this process. The molecular bonds in DNA may be destroyed either by direct ionization from radiation or by being disrupted by nearby ionized water molecules. The resulting mutations may cause cells to lose their function and die, or the cells may survive but lose their ability to control cell division, causing tumors. On Tuesday, the radiation inside the power plant had reached 400 millisieverts (mSv) per hour, which is many times past the 50 mSv annual limit for nuclear power plant workers. Exposure to high radiation increases the likelihood of cancer and if a person receives 1000 mSv within 24 hours, they may experience radiation sickness from the large number of cells dying. Residents within a 80km radius of the reactors have been evacutated for safety.

The crisis has been averted somewhat as some of the reactors have had electricity restored to their cooling systems, but reactor No.4 is still a candidate for potential meltdown. It is suspected that all the water in its cooling system had boiled away and entire wall from its cooling system has been destroyed, shown in the picture below:

Video for an explosion that occured at one of the reactors:
YouTube Preview Image

According to the news, radiation from the nuclear crisis in Japan should be reaching the West Coast at some time today, but it should be so diffuse by the time it reaches North America that it will have no health effects at all.
Resource for the effects of radiation:
http://www.hss.energy.gov/HealthSafety/ohre/roadmap/achre/intro_9_5.html

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Posted in Physical Sciences, Science in the News

Banana Peel Can Remove Toxic Metals From Water!

Posted on March 18, 2011 by | 1 comment

Scientists from Brazil have discovered that minced banana peels are very efficient in removing toxic metals from wastewater. This was found to be 20 times more effective than conventional water treatment methods. The same bunch of peels could be used up to 11 times, as they are efficient metal collectors in their natural state.

The research was done in San Paolo Research Foundation, where they found that banana peels could remove copper and lead from water better than conventional methods such as Na-bentonite, AMP- modified silica gel, expanded perlite and modified peanut husk. The research was conducted in part of green chemistry movement, which aims to development more sustainable water treatment equipment like the new age nano-engineered ceramic water filters.

Bananas are affordable and readily available, this makes a very cheap alternative for large purification plants. You would probably need a lot of it in order to run a plant, but when the finance for treatment plans are slow, they could run on much smaller scales. Although, silica is one material that is really efficient in purifying water, before using it, it needs to be treated with costly toxic materials, and thus makes it seem like a loser when compared to banana peels.

I recently attended a seminar about the banana farm industry in Ecuador, and apparently, all of our bananas come from there! It is also guaranteed that anyone in the world has eaten Ecuadorian bananas at least once in their lifetime. The problem we were discussing in the seminar was not how great Ecuadorian banana’s are, but rather how the pesticides in the banana farms have detrimental effects on the health of the farmers. Banana farms have loads of bugs, worms, flies, anything you name it they got it! So, to get rid of them they spray pesticides in the air (to kill flies), on the bananas (to kill bugs eating the bananas) and deep into the ground (to kill the worms). The toxicity of these pesticide’s are extremely high, and they have severely affected the health of the farmers who work in close proximity with the pesticides over long periods of time. The reason these chemicals do not harm us is because bananas are washed thoroughly before they are exported. However, with the sheer volume of pesticides going on top of the banana peels, I wonder how much of it can actually be washed away?

Video on Banana Pesticides

My thoughts on this issue are, if the discovery of banana peels being efficient purifying agents has anything to do with pesticides that are sprayed onto the bananas. The article does not go in-depth about the chemical reactions that occur on the surface of the banana peel with water, which might suggest that there is something else going on. More research should be done to confirm the science behind the claim. My prediction is that banana peels are good purifying agents because of the combination of low-dose-pesticide-contaminated banana peels with wastewater.

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Posted in Environment, Uncategorized

Depression drugs and their negative effects.

Posted on March 18, 2011 by | 1 comment

The Affected brain

Depression drugs have been used for a long time, however, the negative effects associated with them is well understood. A well-known depression drug is Prozac, which increases the amount of seratonine in the brain and may cause long term effects in the brain. It takes about one month for the drug to affect the person and lower the depression level.

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