Tag Archives: science news

Mercury – NASA’s Fifth Planetary Conquest

Image of Mercury from previous Messenger missions. From NASA.

After years of planning and development, NASA’s space probe Messenger finally fell into Mercury’s orbit Thursday evening. At 9:10 p.m. of March 17, when the last rocket that projected Messenger shut off and the probe fell into Mercury’s gravity pull, scientists at the control room in John Hopkin’s University started in a round of applause.

Mercury is the fifth planet that NASA spacecrafts have orbited. Mercury is the closest planet to the sun and lacks an atmosphere. This means that Mercury’s surface is super heated by the sun during daytime but drops to hundreds of degrees below freezing at night. Also, without an atmosphere, Mercury’s surface is heavily cratered. The vast temperature different implies that ice could be found inside the craters. The Mercury probe hopes to bring back a year of photography that would help in the research of the creation of Mercury and its composition. With this goal in mind, surveillance of the probe is needed for the next few days. Constant checks on the probe’s health systems, testing of the scientific equipment that is on board is essentially so that the vast amount of data can be collected and  transmitted back to Earth.

This massive project started in 2004 with a budget of $446 million. Hopefully, the probe will bring back valuable data that would useful for planetary scientists to determine the evolution of Mercury.

Messenger also hits close to UBC as one of the Earth and Ocean Science professors, Dr. Catherine Johnson, participated in the project. Dr. Johnson is a participating scientist in the project and hopes to discover the reasons behind Mercury’s magnetic field. The probe Messenger hopefully will gather data that will be of use to Dr. Johnson.

The New Heavyweight Champion of the Universe

EDIT: added in another image of star cluster R136

Ladies and gentlemen, let me introduce you, to Hypergiant “blue” R136a1, “The New” Solar Mass Heavyweight Champ! Weighing in at an estimated 265 solar masses, he may very well be the most massive star in our universe! He’s  so big, that scientists are baffled by how he came to be.

Size Comparison for R136a1

You heard it folks, there’s a newly discovered star, that’s so heavy that it disputes current models of how stars may be formed. R136a1 was discovered last year with the findings published in July 2010. It’s found in a star cluster known as R136 that’s 165,000 light-years away.

In 2005 NASA had released an article which suggested that in our current era of the universe, stars cannot exceed 150 solar masses (i.e. 150 times the mass of the sun) otherwise they would violate the Eddington Limit. This limit is where the radiation force outwards of a star is equal to the gradational force pulling inwards. Stars bigger than this would have too much out flowing radiation that they would eject all their gaseous matter into space.

This may be the case for R136a1: scientists speculate it was actually much heavier at its formation and may have lost as much as 50 solar masses through continuous emission of stellar winds in the last million years due to its instability. So, how did R136a1 come to be? Scientists speculate that its ridiculous size may be attributed to several young stars colliding together to form a single object.

Size Comparison for VY Canis Majoris

One thing to keep in mind is that while R136a1 is the heaviest known star, at only 35 solar radii (i.e. 35 times the radius of the sun), it is certainly not the largest. The title of “biggest star” belongs to VY Canis Majoris that is 1800-2,100 solar radii in size! At the same time, it is only 30 times the mass of our sun.

As for its fate, R136a1 is too big to form a black hole and may instead explode as hypernova (an explosion equivalent to over  100 supernovae). Of course, that’s only if it doesn’t blow all of its matter into space before then..

The original article can be found here (#83, “The Biggest Star of All”):  http://discover.coverleaf.com/discovermagazine/201101?pg=76#pg76

NASA’s 2005 article can be found here:  http://www.nasa.gov/home/hqnews/2005/mar/HQ_05071_HST_galaxy.html

For more general information on hypergiant stars, see:  http://en.wikipedia.org/wiki/Hypergiant

Hubble - R136 - Stellar Nursery

Man Made Proteins

In ancient times the Greeks had myths about creatures that had the best parts of animals put together. One example is a griffon, which is half lion and half eagle. Some research being conducted at Princeton University may lead to organisms with the best of the best genes possible.

Scientists at Princeton have created new genetic sequences not found in nature that can sustain life. They created a list of proteins not found in nature that would fold into a 3D structure on its own.  They then tried putting these proteins into some living cells to see if the synthesized proteins actually do anything.

The scientists inserted the proteins into some mutated bacteria cells that were missing some genes essential for life. The control group that had the deleted genes but no added proteins did not survive. Mutant bacteria with the added proteins survived and formed colonies. This showed the scientists that synthetic proteins can be as useful at sustaining life as ones found in nature. This is a big step in fabricating life because the new proteins bear no resemblance to the natural proteins that it replaced.

There are many combinations of amino acids that can be combined to form a protein and nature has only created a small portion of the possible combinations. If scientists continue this type of research, they may find proteins that are more efficient at their function than their natural counterparts. We could eventually be putting the best pieces of genetic code together to make super organisms.

The origional article can be found here: http://www.princeton.edu/main/news/archive/S29/43/27E55/index.xml?section=topstories

What to trust in making decisions; Cognitive thinking or Sientific methods?

We have all evolved to associate one thing to the other. We associate by thinking; finding and looking for meaningful patterns in our surroundings. Another reliable way to associate one thing to the other is by the use of scientific methods. The problem over  here is what to trust in  making a decision, our cognitive thinking or the scientific method?

In recent years, there has been a seeming connection between autism and MMR-vaccines. The parents of the children diagnosed of Autism, are trying to look for a causal link between this complex developmental disability and vaccines that the children had received.

In 1998, a British surgeon, Andrew Wakefield, published a paper claiming that the MMR-vaccine had a causal link to Autism. He proposed that the measles virus traveled to the children’s intestines causing intestinal damage. This damage then allowed brain damaging proteins to enter their blood stream. Dr.Wakefield used stories of 8 children who had developed symptoms of autism within a month of receiving the vaccines.

Here is the article from Wall street Journal that i came across Junk Science Isn\’t a Victimless Crime.

These findings fueled the debate over vaccine safety and lead many people to a general distrust in vaccines.

This type of study has been replicated many times around the world and each time no causal  link has been found. The following two articles from New Scientist proves that MMR-vaccine has no causal link to Autism; Autism rises Despite MMR Ban in Japan and MMR and Autism not linked, finds giant study.

I do not think Dr. Wakefield’s paper was statistically right. He based his conclusion on a very small sample size (about 12 children). He should have used  a way larger sample size as in the other two studies disproving the existence of a causal link (more than 30,000 or half a million children).

Overall, What do we believe; Is there a causal link between MMR-vaccine and Autism? In spite of knowing that the research linking MMR-vaccine to Autism has some discrepancies, we still feel that there is a link. Do not forget we have the ability to overcome our feelings in a situation and replace them with a logical and scientific reasoning that would serve us better and help us advance in life.

If further interested, here is part 1 of 10 of Dr. Andrew Wakefield’s interview on his MMR study by Dr. Mercola.

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