NASA SDO captures long solar filament

Credit: SDO

A very long filament hung across the sun’s surface for over a week from July 31 to Aug. 6, 2014.

The filament appears as the dark line going diagonally across the center of the sun in this image.

Filaments consist of clouds of cooler gas raised above the sun’s surface by magnetic forces.

Normally they exhibit a great deal of instability and break apart in days or even hours.

This image was obtained in the 191 Angstrom wavelength of extreme ultraviolet light, and has been tinted red instead of the usual brown colour.

Astronomers find stream of gas, 2.6 million light years long

The bridge of gas (shown in green) stretches from the large galaxy at the bottom left to the group of galaxies at the top. 

A third nearby galaxy to the right also has a shorter stream of gas attached to it. 

The three insets show expanded views of the different galaxies and the green circle indicates the Arecibo telescope beam.

Credit: Rhys Taylor /Arecibo Galaxy Environment Survey /The Sloan Digital Sky Survey Collaboration

Atronomers and students have found a bridge of atomic hydrogen gas 2.6 million light years long between galaxies 500 million light years away.

They detected the gas using the William E. Gordon Telescope at the Arecibo Observatory, a radio astronomy facility of the US National Science Foundation sited in Puerto Rico.

The results are published today in a paper in Monthly Notices of the Royal Astronomical Society.

The stream of atomic hydrogen gas is the largest known, a million light years longer than a gas tail found in the Virgo Cluster by another Arecibo project a few years ago.

Dr Rhys Taylor, a researcher at the Czech Academy of Sciences and lead author of the paper, said "This was totally unexpected.

We frequently see gas streams in galaxy clusters, where there are lots of galaxies close together, but to find something this long and not in a cluster is unprecedented."

It is not just the length of the stream that is surprising but also the amount of gas found in it. Roberto Rodriguez, a 2014 graduate from the University of Puerto Rico in Humacao who worked on the project as an undergraduate, explained "We normally find gas inside galaxies, but here half of the gas, 15 billion times the mass of the Sun, is in the bridge. That's far more than in the Milky Way and Andromeda galaxies combined!"

The team is still investigating the origin of the stream. One notion surmises that the large galaxy at one end of the stream passed close to the group of smaller galaxies at the other end in the past, and that the gas bridge was drawn out as they moved apart, while a second notion presumes that the large galaxy plowed straight through the middle of the group, pushing gas out of it.

The team plan to use computer simulations to find out which of these ideas can best match the shape of the bridge that is seen with the Arecibo Telescope.

The project involved three undergraduate researchers: Roberto Rodriguez and Clarissa Vazquez from UPR Humacao, and Hanna Herbst, now a graduate student at the University of Florida. Dr Robert Minchin, a staff astronomer at Arecibo Observatory and the principal investigator on the project, said "Student involvement is very important to us."

"We are proud to be inspiring the next generation of astronomers, and particularly proud of the involvement of Puerto Rican students."

The bridge was found in data taken between 2008 and 2011 for the Arecibo Galaxy Environment Survey (AGES), which is using the power of the Arecibo Telescope to survey a large area of sky with a high level of sensitivity.

Journal Reference: R. Taylor, R. F. Minchin, H. Herbst, J. I. Davies, R. Rodriguez And C. Vazquez. The Arecibo Galaxy Environment Survey – VII. A dense filament with extremely long H i streams. Monthly Notices of the Royal Astronomical Society, 2014 DOI: 10.1093/mnras/stu1305

These tunneling clouds in the skies are... long

The Morning Glory cloud is a special cloud that forms at altitudes of up to two kilometres and stretches for as long as 1,000 kilometers long.

It happens when flowing, moist and cool air meets the inversion layer where air temperature atypically increases with height.

This photo was taken by photographer Mick Petroff from his airplane near the Gulf of Carpentaria, Australia in 2009. 

NASA SDO Image: long filament of solar material - HD Video

A long filament erupted on the sun on August 31, 2012, shown here in a movie captured by NASA's Solar Dynamics Observatory (SDO) from noon EDT to 1:45 a.m. the next morning.

The filament lies in the lower left corner of the sun.

The movie shows light at 304 Angstroms and 171 Angstroms, both of which help scientists observe the sun's atmosphere, or corona.

A long filament of solar material that had been hovering in the sun's atmosphere, the corona, erupts out into space.

The coronal mass ejection, or CME, travelled at over 900 miles per second. 

The CME did not travel directly toward Earth, but did connect with Earth's magnetic environment, or magnetosphere, causing auroras to appear on the night of Monday, September 3.

Picture: NASA/GSFC/SDO / Rex Features