Is It true? Planetary protection regulations stymieing Mars missions, says researchers

Is It true? Earth is being cooled by pollutants, says researchers

We’ve heard quite a bit on the climate-change effects of pollution, but much of it has centered on increased global temperatures, resulting in reduced ice caps and particularly volatile storms that have ravaged many places around the world in the last decade. Now a new study has shown that pollutants can also have a cooling effect on our planet via their effects on clouds.

Clouds can have both a warming and a cooling effect on our planet, depending on their formation. Condensed water droplets are the substance of clouds, with the size of the particles upon which they are suspended being directly related to the brightness of clouds as determined from above. Obviously, the brighter a cloud, the more sunlight it reflects away from our blue marble, something that has been widely known. In this study, the effects of pollution on clouds was looked at, in particular the effects of organic compounds released by pollutants, which make their way upwards and serve as particles. Because of their nature, the pollutant particles cause larger droplets to form, and the result is brighter clouds, which in turn reflect more sunlight. Says the researchers, though, the effects aren’t likely powerful enough to combat increasing global temperatures. Said the project’s author Gordon McFiggans: “More cloud droplets lead to brighter cloud when viewed from above, reflecting more incoming sunlight. We did some calculations of the effects on climate and found that the cooling effect on global climate of the increase in cloud seed effectiveness is at least as great as the previously found entire uncertainty in the effect of pollution on clouds.” [via Science World Report] Earth is being cooled by pollutants, says researchers is written by Brittany Hillen .

Is It true? Rare long gamma ray bursts caused by supergiant star’s death, says researchers

There are two types of gamma-ray bursts: short and long. The short GRBs last a very short duration, a maximum of two seconds but sometimes even less. The longer ones are still relatively short, coming in at more than two seconds and sometimes several minutes, with the longest ones typically clocking in between 20 seconds and 50 seconds. A rare type of long GRB has been seen in action a couple times throughout recent years, however, and scientists finally have an answer about what causes them.

Starting in 2010, a new type of gamma ray burst was identified that lasted much longer, followed by two more over the months to 2012. The longest of the three is called GRB 111209A, and is the longest ever noted, having lasted a whopping 7 hours. Such massively long gamma rays have confused astronomers, with the fairly recent phenomenon having only occurred a few times. This led astronomers to utilize NASA’s Swift telescope, a European Space Agency’s satellite, and more to study the super gamma ray GRB 111209A, which occurred in late 2011. By doing this, they came to the conclusion that the death of a massive star, which is said to be sized far beyond our sun’s mass and forming a black hole, is responsible for the burst. Bruce Gendre, who led the study, said: “We have observed the longest gamma ray burst in modern history, and think this event is caused by the death of a blue supergiant. It caused the most powerful stellar explosion in recent history, and likely since the Big Bang occurred.” The findings were discussed earlier today in Tennessee in a meeting sponsored by the University of Alabama. [via Science Recorder] Rare long gamma ray bursts caused by supergiant star’s death, says researchers is written by Brittany Hillen .