Friday, January 30, 2015

Galactic Herding - How do galaxies join up?

Most galaxies travel through space along with lots of other types, shapes, and sizes. Some group galaxies have mostly ancient stars, while others hang with the new cosmic kids.

So do they all share a common origin? Or just chance alignments? Do galaxy groups pick up “strays” along the way?

A new image from the Gemini Multi-Object Spectrograph (GMOS), at the Gemini North telescope located on Mauna Kea, Hawaii shows different galaxy types at the great distance of 300 million light years away. Of interest is a perfect alignment of three galaxies in a precise equilateral triangle: blue-armed spiral NGC 70 at top, elliptical galaxy NGC 68 to its lower right, and lenticular galaxy NGC 71 to its lower left. 

The massive blue spiral (NGC 70) spans 180,000 light-years or nearly twice the extent of the Milky Way’s reach. Its spiral arms look blue because of active regions of star formation (i.e., young hot stars burn with an intense blue light).

In contrast, NGC 68 (lower right) is a much older system known as an elliptical galaxy. It is about half the size of the blue spiral and hosts little dust and gas, so star formation and spiral are absent; the galaxy’s overall yellowish hue shows most of its stars are old and red. 

Although NGC 71 looks like NGC 68 (smooth glow, below and to the left of NGC 68) it's a lens-shaped galaxy seen face on, so it appears more like a sphere. Lenticular galaxies appear trapped between types: like a spiral galaxy it has a bulge and a disk but no spiral arms; but, like an elliptical galaxy, it is missing dust and gas. Maybe galaxies like NGC 71 were originally spiral systems and somehow lost their interstellar material.

Past the triangle to the lower left is the Group’s fourth brightest member, a barred spiral galaxy known as NGC 72. Its main bar crosses its nucleus with dusty arms that wind from each end of the bar and form a nuclear ring – showing recent star formation. Our Milky Way Galaxy has a similar bar feature nearly 30,000 light-years across, as well as a circumnuclear ring.

This new information gives astronomers and astrophysicists a lot to think about. Apparently in the distant universe all types of galaxies can be friends.
Go science!

Thursday, January 22, 2015

New Antibiotic from Soil Bacteria

Just when parents are busy keeping toddlers out of the dirt, scientists find a previously unknown soil bacteria that makes a powerful Gram-positive bacteria-targeting antibiotic. It turns out that it kills bad players like methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacterium tuberculosis. Wahoo! Staph was definitely getting out of hand so this is good news!
The new bacterium, called teixobactin, lives in the soil and can't be grown in the lab using common methods. However researchers, Lewis and Slava Epstein, came up with an innovative technique where a soil sample is diluted with agar and suspended in a chamber surrounded by a semi-permeable membrane. Their results were published on January 7th in Nature.

This unique growth method allows the bacterium to grown more like it does in nature and allows a level of biodiversity that is missing in current culture methods. The antibiotic has not yet been proven to kill bacterial infection in humans, but assuming it works after more testing, “a drug like this must be reserved for serious diseases and not given to general practitioners to spread around like aspirin." 

“The rate of evolution of large-scale resistance will depend on the dosage and frequency of [the antibiotic’s use],” added Princeton microbiologist Julia Bos.

So with quiet optimism things are looking up in the fight against infection...if we are careful. Go science!

Wednesday, January 7, 2015

Gamma-ray Flashes & Storms

Thunderstorms create about a 1000 quick bursts of gamma rays (i.e., high energy light on Earth). Recent data from NASA's Fermi Gamma-ray Space Telescope compared to ground-based radar and lightning detectors, gave scientists detailed information on the different types of thunderstorms and their produced energy.

Terrestrial gamma-ray flashes (TGFs), were discovered in the 1990s by NASA's Compton Gamma-Ray Observatory. TGFs, lasting less than a thousandth of a second, are poorly understood.

"Remarkably, we have found that any thunderstorm can produce gamma rays, even those that appear to be so weak a meteorologist wouldn't look twice at them," said Themis Chronis, who led the research at the University of Alabama in Huntsville (UAH).

The Fermi data, combined with info from ground-based radar and lightning, shows that terrestrial gamma-ray flashes come from a diversity of storms and may be more common than earlier expectations. In fact, the upper part of an intracloud lightning bolt disrupts the storm's electric field creating an avalanche of electrons that surge upward at high speed. These fast-moving electrons are deflected by air molecules and emit gamma rays, creating a TGF.  

The new study confirms previous findings that TGFs tend to occur near the highest parts of a thunderstorm, between about 7 and 9 miles (11 to 14 kilometers) high.

As climate change unfolds, it will be interesting to see if TGFs increase or decrease with storms. I'm sure the Fermi folks will keep an eye to the skies. Go science!

Friday, January 2, 2015

May the force of New Year resolutions be with you!

Happy New Year! May the Resolutions force be with You! 

I have been luxuriating on the Oregon coast in the rain as well as hiking through old growth forests and celebrating the holidays with family between raindrops. I even had time to engage my newly resurrected love of photography. You can check out some of my mostly science and nature images here

If you are a science educator, I'd love to connect on Pinterest (where I contribute frequently) or FB (I check in ~ weekly) or Twitter (occasionally). 

As a science geek and scifi nerd, I am always interested in the latest sites, movies, and news. Send those along as you find them. Here is what I came across lately. 

This new NASA-led study estimates that tropical forests absorb 1.4 billion metric tons of carbon dioxide out of a total global absorption of 2.5 billion -- more than boreal forests in Canada, Siberia and other northern regions.

More science news updates as they happen. Until then Go Science!