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Skepticism, Medicine and Science News

Hubble Captures Two Ginormous Stars

A new picture from the Hubble Space Telescope shows two massive stars, WR 25 and Tr16-244, located in the open cluster Trumpler 16. This cluster lies within the Carina Nebula, approximately 7500 light years from earth. The nebula is home to many massive stars, including Eta Carinae, a supermassive luminous blue variable star with a luminosity four million times that of our sun, and a mass of 100-150 solar masses. WR 25 and Tr16-244 are not as big as Eta Carinae, but they are still pretty massive. 

WR 25 is located near the centre of the picture (the most blue of the big stars). It is binary star, and the largest of the two stars is a Wolf-Rayet star with a mass of about 50 solar masses. Wolf-Rayet stars are stars with a mass of >20 solar masses, and they loose their mass extremely rapidly due to a strong solar wind, typically about nine orders of magnitude more rapidly than our sun. The smaller star in the binary system is thought to have a mass of about half that of the other. 

Tr16-244 is located just to the left and up from WR 25, and is the third brightest star in the picture. The second brightest is a low-mass star much closer to earth (and thus it appears more luminous). This is a triple star, two of which are so close to each other that it took a while to determine they were in fact two separate stars. The third uses hundreds of thousands of years to orbit the first two. 

These new observations were made as part of a project led by Jesús Maíz Apellániz from the Instituto de Astrofísica de Andalucía in Spain, and consist of astronomers from the US, Argentina, Spain and Chile.

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November 27, 2008 Posted by | Astronomy | , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

Olympus BioScapes Digital Imaging Competition 2008

The 5th Olympus BioScapes Digital Imaging Competition has recently announced its winners and honorable mentions for 2008. According to the competition rules, all images must be of things that are, or once were, living, and light microscopy must be part of the imaging technique. A panel of judges then, well, judges the images, and the top 10 receives prizes. This years winners and honorable mentions can be found at the competition website. The winner this year was Spike Walker who captured this picture of a “Fairy Fly” Wasp taken using Rheinberg illumination:

This years winner. The wasp itself is only about 0.21 millimetres long. 

November 19, 2008 Posted by | General Science | , , , , , , , , , , , , , , , | Leave a comment

Voyage Into Space

I stumbled upon this news item in Phil Plait’s blog, and it is extremely cool. The European Southern Observatory, or ESO, just released the deepest ultraviolet image of the Universe yet. It was taken by the Very Large Telescope (yes, that is it’s name, and it’s really a set of four telescopes working together, namely the Antu telescope, the Kueyen telescope, the Melipal telescope, and the Yepun telescope), and contains more than 27 million pixels.

    

This is a compressed version of the image, so for full resolution go here. When I first saw this picture i thought all the bright dots were stars, but no, they are in fact galaxies. Some of them are as far as 10 billion light years away, which means they are really, really young. I recommend you take a look at Phil Plait’s post about this picture. Being an astronomer he knows what he’s talking about, something I really don’t most of the time.

November 8, 2008 Posted by | Astronomy | , , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

Chandra X and the Crab Nebula

In 1999 NASA launched the Chandra X-Ray Observatory, which is part of NASA’s Great Observatories together with HubbleSpitzer, and Compton. Chandra X recently took a beautiful picture of the Crab Nebula

According to NASA, this is the first picture clearly showing the faint boundary of the nebula‘s X-ray emitting pulsar wind nebula. The white dot in the center is the neutron star (or pulsar) powering the nebula. Pulsars are essentially highly magnetized neutron stars that emit concentrated beams of electromagnetic radiation, which can only be observed when directed directly at earth. A pulsar will thus appear to pulsate (hence the name) when observed, and the regularity of this pulsing effect has been shown to be extremely precise, even to the level of an atomic clock. Anyhow, the rapid rotation of the pulsar in question combined with the intense electromagnetic field generated creates jets of matter and antimatter shooting out from the poles of the pulsar, and a strong wind flowing out in the equatorial direction. The inner ring surrounding the pulsar is possibly a shock wave serving as a boundary between the nebula and the matter/antimatter jets, and electrons and positrons flow outward from it, producing an extended X-ray glow. The shape of the nebula is related to the strong magnetic field, and the dark spots on the right and left is thought to be the result of a toroidal (doughnut) shaped magnetic field from a progenitor star.

November 7, 2008 Posted by | Astronomy | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

Chandrayaan-1

A little over a week ago, India launched its first lunar satellite, Chandrayaan-1. The objective of the mission is, among other things, to carry out high resolution mapping of topographic features in 3D, determine distribution of various minerals and elemental chemical species and to search for surface/sub-surface water-ice at the lunar poles. Well, to test the on-board camera, Chandrayaan-1 (which translates to “moon craft”) took some really good pictures of the earth on October 29th. 

Click here for full resolution, here for another picture and here to read more about the camera test.

November 2, 2008 Posted by | Astronomy | , , , , , , , , , , , , , , , , , | Leave a comment

New Scientist Eureka Prize for Science Photography

The Eureka Prize for Science Photography is a contest held by the New Scientist magazine, and this years submissions are currently on display at the Questacon Centre in Canberra, Australia. The exhibition will be open from 1 November 2008 to 7 January 2009. Some of the images are: 

A baby kangaroo inside its mothers pouch – Jason Edwards 

More inside: Continue reading

November 1, 2008 Posted by | General Science | , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment

2008 Wildlife Photographer of the Year

The 2008 Wildlife Photographer of the Year competition is an annual event hosted by the Natural History Museum in London and BBC Wildlife Magazine. The winners this year has just been announced, and they include some absolutely striking pictures. The overall winner was Steve Winter for his picture of a leopard in a snowstorm:

Other awards in separate categories were also announced, and some of my favorite images are:

Continue reading

October 31, 2008 Posted by | Other | , , , , , , , , , , , , , , , , , , , , , , , , , | Leave a comment