New Earth?
Wednesday 25 April 2007 at 07:26 amThis is "old" news, but bloody hell!
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The new planet is not much bigger than the Earth
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Enlarge ImageThe planet orbits the faint star Gliese 581, which is 20.5 light-years away in the constellation Libra.
Scientists made the discovery using the Eso 3.6m Telescope in Chile.
They say the benign temperatures on the planet mean any water there could exist in liquid form, and this raises the chances it could also harbour life.
"We have estimated that the mean temperature of this 'super-Earth' lies between 0 and 40 degrees Celsius, and water would thus be liquid," explained Stephane Udry of the Geneva Observatory, lead author of the scientific paper reporting the result.
"Moreover, its radius should be only 1.5 times the Earth's radius, and
models predict that the planet should be either rocky - like our Earth
- or covered with oceans."
'Is there life anywhere else?' is a fundamental question we all ask
Alison Boyle
London Science Museum
Xavier Delfosse, a member of the team from Grenoble University, added: "Liquid water is critical to life as we know it."
He believes the planet may now become a very important target for future space missions dedicated to the search for extra-terrestrial life.
These missions will put telescopes in space that can discern the tell-tale light "signatures" that might be associated with biological processes.
The observatories would seek to identify trace atmospheric gases such as methane, and even markers for chlorophyll, the pigment in Earth plants that plays a critical role in photosynthesis.
'Indirect' detection
The exoplanet - as astronomers call planets around a star other than the Sun - is the smallest yet found, and completes a full orbit of its parent star in just 13 days.
EXOPLANET GLIESE 581 C
Mass: Five times Earth's mass
Orbit: 13 days
Temperature: 0C - 40C
Distance: 20.5 light years
Constellation: Libra
Indeed, it is 14 times closer to its star than the Earth is to our Sun.
However, given that the host star is smaller and colder than the Sun - and thus less luminous - the planet nevertheless lies in the "habitable zone", the region around a star where water could be liquid.
Gliese 581 was identified at the European Southern Observatory (Eso) facility at La Silla in the Atacama Desert.
To make their discovery, researchers used a very sensitive instrument that can measure tiny changes in the velocity of a star as it experiences the gravitational tug of a nearby planet.
Astronomers are stuck with such indirect methods of detection because current telescope technology struggles to image very distant and faint objects - especially when they orbit close to the glare of a star.
The Gliese 581 system has now yielded three planets: the new super-Earth, a 15 Earth-mass planet orbiting even closer to the parent star, and an eight Earth-mass planet that lies further out.
The latest discovery has created tremendous excitement among scientists.
Gliese 581 is much cooler and dimmer than our own Sun
Of the more than 200 exoplanets so far discovered, a great many are Jupiter-like gas giants that experience blazing temperatures because they orbit close to hot stars.
The Gliese 581 super-Earth is in what scientists call the "Goldilocks Zone" where temperatures "are just right" for life to have a chance to exist.
Commenting on the discovery, Alison Boyle, the curator of astronomy at London's Science Museum, said: "Of all the planets we've found around other stars, this is the one that looks as though it might have the right ingredients for life.
"It's 20 light-years away and so we won't be going there anytime soon, but with new kinds of propulsion technology that could change in the future. And obviously we'll be training some powerful telescopes on it to see what we can see," she told BBC News.
"'Is there life anywhere else?' is a fundamental question we all ask."
SEM of CBR
Sunday 22 April 2007 at 4:19 pmHere are some SEM images of Columbia River Basalt. These images are the same field of view of the same specimin.
My First SEM
Thursday 12 April 2007 at 8:38 pm Here is my first Scanning Electron Microscope Image. If printed it is 4000x image of a copper wire mesh.
One
Sunday 08 April 2007 at 5:34 pm
One year ago Derek and I stood on a bridge at Reed college. It was night and there were glowing blue lights on the bridge overlooking a calm lake. We kissed for the first time and later declared April 8th, 2006 as when we became an official couple. It is now one year later. Today is our one first anniversary, a day which I often wondered if I would ever see. The past year has rivaled those where I've been on the field. He gave me a ring and I give him a Japanese Maple bonsai tree from Saturday Market. You can read about it in Derek's blog.
I love him.
Spring Term Is Here
Tuesday 03 April 2007 at 11:54 pmIt is time for my quarterly updates for my funs and thrills in academia. I shall first cover my real classes, divulge information on the two classes I am a teacher assistant for, and then begin my journaling on my return as a University Studies Mentor.
Normal Classes
I am enjoying a break this term by taking only 9 graduate level credits in three courses. My first real class at 4 credits is on roadside ecology. Most of my science background is in the natural and physical sciences so I felt it would be appropriate that I should expand my horizons into the environmental sciences. That and I have a classmate who is also a first year graduate student in the Center for Science Education. The class content will cover how roads affect local ecology such as polluted water runoff to habitat isolation and fragmentation. The professor knows only a little on the topic. As a result there is a guest lecture almost every day by people from government agencies like the Oregon Department of Transportations, as well as the academic folk -- we have several people coming in from the University of California in Davis. The course will culminate with an 8 page long research proposal that, if I was interested, I could get funding for through some money PSU has acquired to research such topics. While I wont be pursuing that option, I will probably write up a proposal investigating invasive species.
Scanning Electron Microscopy is my next class for four credits. This is a project based class. There will be lecture and lab demonstrations for the first four weeks where we will be learning how to use a SEM and what information we can collect from using one. On the fifth week is a midterm where we earn our certification for using SEMs. I do not know if this certification is some PSU thing allowing me to use the lab unsupervised, or if it carries weight outside of campus. The remaining 5 weeks will be finishing our projects. The professor looked up our majors and departments before class. He told me that he is working for an organization that would be very interested in having a future teacher help out on a project for them. I have no idea how SEMs relate to education, but I am egger with anticipation.
Teaching Assisstance
Natural Science Inquiry is a sophomore level general-education class that is specifically targeted for non science majors. The objective of this class is to teach science by doing science. The course content focuses on transportation. While not science this curriculum still follows and teaches the same basic principles of science (asking questions, data collection, defending conclusions) as science but covers a more accessible topic. The professor wants to co-teach this course with me, so there will be several times I will be in front of the room.
Astronomy is being taught by a nerdy yet attractive (jealous yet Derek :) ) physics graduate student -- a different one from last term. I can tell just after the first day that this will be a major improvement over the previous term. My roll will be in the background as I will only be grading. I do plan on attending all the lectures as they are quite good and make some notes about how he is successful in teaching the content.
Mentoring
As it is late I will give this its own entry on a later date.
