The interstellar stuff that became incorporated into the planets and life on Earth has younger cosmic roots than theories predict, according to the University of Chicago postdoctoral scholar Philipp Heck and his international team of colleagues.
Heck and his colleagues examined 22 interstellar grains from the Murchison meteorite for their analysis. Dying sun-like stars flung the Murchison grains into space more than 4.5 billion years ago, before the birth of the solar system. Scientists know the grains formed outside the solar system because of their exotic composition.
When you go to New York City, to Central Park, to the American Museum of Natural History, to the Hayden Planetarium, to a seminar hosted by Neil deGrasse Tyson, on the entire cosmos, you might think it would be hard to figure out who 'the star' will be.
Doom and gloom types always want to lament that the presence of people is killing the Earth. Not so, say California Institute of Technology (Caltech) scientists. At least on a cosmic scale, the presence of life may increase longevity for planets.
In traditional thinking, a billion years from now the ever-increasing radiation from the sun will have heated Earth into inhabitability, causing the carbon dioxide in the atmosphere that serves as food for plant to disappear. The oceans will evaporate and all living things will disappear.
Maybe not quite so soon, say researchers from Caltech, who have come up with a mechanism that doubles the future lifespan of the biosphere while also increasing the chance that advanced life will be found elsewhere in the universe.
I've often talked about how amateurs still can make contributions in modern astronomy, making us unique among the sciences. Well, 14-year old Caroline Moore became the youngest person to discover a supernova, through diligence and drive. The story of her find of SN2008ha
is both a great character piece, and an example of what a motivated and skilled person can accomplish in 8 months.
At parties, some people are intimidated when I say I'm an astronomer (or, worse, astrophysicist). They assume I'm a haughty ivory tower genius who laughs at little people like them. It's so hard to reassure them that, no, I don't laugh, I merely chuckle. But I do feel it's my duty to help make life easier for the non-astrophysicists out there.
So, say you're at a party and you meet a famous astronomer. It doesn't matter which one, we're all famous (or at least published). Here are 6 things not
- I'm an Aquarius, can you tell me my future?
- I'm angry because Pluto isn't a planet anymore!
- What will happen in 2012 when the Earth, sun and the center of our galaxy line up?
A recent survey of 'dark' gamma-ray bursts, which are bright in gamma- and X-ray emissions, but have little or no visible light, are giving us a look into the dusty corners of otherwise dust-free galaxies.
Star formation occurs in dense clouds that quickly fill with dust as the most massive stars rapidly age and explode, spewing newly created elements into the interstellar medium to seed new star formation. Hence, astronomers presume that a large amount of star formation is occurring in dust-filled galaxies, although actually measuring how much dust this process has built up in the most distant galaxies has proved extremely challenging.
Space weather can kill astronauts. This is one of the motivations for funding space weather. Solar events-- flares, particle storms, and coronal mass ejections-- can knock out GPS and cell phone reception, screw up radio and radar, and endanger airline pilots flying the polar routes. All of these damaging effects are well worth mitigating.
But what about circumstances higher up?
In an article titled Fake Astronaut Gets Hit by Artificial Solar Flare
, NASA reports on their upcoming experiment to see just how much damage a solar flare would cause to an unprotected astronaut.
Mercury, closest planet to the sun, is as hot as you would expect, with daytime temperatures of 800 degrees Fahrenheit/450 degrees Celsius and because of its small size, its gravity is weak, only about 38 percent of Earth's.
These conditions make it hard for the planet to hold on to its extremely thin atmosphere, which can can only be seen by special instruments attached to telescopes and spacecraft like MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging). Even then it's not easy because Mercury's magnetic field gets in the way. MESSENGER's first flyby on January 14, 2008, confirmed that the planet has a global magnetic field, as first discovered by the Mariner 10 spacecraft during its flybys of the planet in 1974 and 1975.
We're somewhat lost in how to meet future carbon footprint goals. Heck, Germany should have been able to just close a few Soviet-era East German factories and hit their Kyoto protocol targets but even they couldn't do it.
The answer, as always, may be in nature. Some parts of outer space are great at getting rid of excess carbon, including an unusual carbon-rich star that was part of a mystery stellar explosion recorded in 2006.
I believe that a scientist looking at nonscientific problems is just as dumb as the next guy.
- Richard Feynman
I just read a neat HST result on dark matter on slashdot.org. I also enjoy peeking at Astronomy Picture of the Day to find out about stuff I don't know. Basically, I get my fix from the same sites I recommend to others curious about astronomy. So I'm not just a professional astronomer. I'm an astronomer fan when it comes to fields other than what I work on.