Tag Archives: astronomy

Unravelling the Web of a Cosmic Creeply-Crawly

Unravelling the Web of a Cosmic Creeply-Crawly

20140109 Ray Villard & Nicky Guttridge of Space Telescope Science Institute —

Cosmic Creeply-Crawly Tarantula Nebula
This huge Hubble Space Telescope mosaic of Tarantula Nebula, spanning a width of 600 light-years, shows a star factory of more the 800,000 stars being born. (20140109) Image by NASA, ESA, and E. Sabbi (STScI)


This new Hubble image is the best-ever view of a cosmic creepy-crawly known as the Tarantula Nebula, a region full of star clusters, glowing gas, and dark dust. Astronomers are exploring and mapping this nebula as part of the Hubble Tarantula Treasury Project, in a bid to try to understand its starry anatomy.

The Tarantula Nebula is located in one of our closest galactic neighbours, the Large Magellanic Cloud. Hubble has released images of this celestial spider several times before: in 2004 (heic0416), 2010 (heic1008), 2011 (heic1105) and 2012 (heic1206). While these images show striking panoramic views of this turbulent region, this new image gives us the deepest and most detailed view yet.

Created using observations taken as part of the Hubble Tarantula Treasury Project (HTTP), this image is composed of near-infrared observations from both Hubble’s Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS). Due to the combination of infrared filters in this image a purple haze fills the frame, with deep red wisps of dust and bright stars scattered throughout.

This region is an example of an HII region — a large cloud of partially ionised hydrogen within which new stars are being born. Visible to the left of centre is a sparkling star cluster known as R136. It was initially identified as a star, but astronomers puzzled over how one single monstrous star could ionise a giant HII region. However, astronomers later realised it was actually a cluster of stars: a super star cluster.

R136 will eventually become a globular cluster: a spherical ball of old stars that orbits around the centre of its host galaxy. R136 is so massive that it contributes greatly to the Tarantula’s brightness, emitting most of the energy that makes the nebula so visible.

The Hubble Tarantula Treasury Project (HTTP) is scanning and imaging many of the stars within the Tarantula, mapping out the locations and properties of the nebula’s stellar inhabitants. These observations will help astronomers to view the nebula and piece together an understanding of the nebula’s structure [1].

This new image is being released today, 9 January 2014, at the 223rd meeting of the American Astronomical Society in Washington, DC, USA.

Notes
[1] This image of 30 Doradus is also the focal point of an iBook on stellar evolution aimed at children with visual imparments. The book, called “Reach for the Stars: Touch, Look, Listen, Learn” is produced by Elena Sabbi — the lead researcher on this Hubble image — and her collaborators. More information can be found here.



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Solar Activity Not a Key Cause of Climate Change

December 23, 2013 From the University of Edinburgh…

Solar flare on the sun.

STORY HIGHLIGHTS

• Climate change has not been strongly influenced by variations in heat from the sun.

A new scientific study shows climate change has not been strongly influenced by variations in heat output from the sun.

The findings overturn a widely held scientific view that lengthy periods of warm and cold weather in the past might have been caused by periodic fluctuations in solar activity.

Volcano impact

Research examining the causes of climate change in the northern hemisphere over the past 1000 years has shown that until the year 1800, the key driver of periodic changes in climate was volcanic eruptions.

These tend to prevent sunlight reaching the Earth, causing cool, drier weather. Since 1900, greenhouse gases have been the primary cause of climate change.

The findings show that periods of low sun activity should not be expected to have a large impact on temperatures on Earth, and are expected to improve scientists’ understanding and help climate forecasting.

Historical data

Scientists at the University of Edinburgh carried out the study using records of past temperatures constructed with data from tree rings and other historical sources.

They compared this data record with computer-based models of past climate, featuring both significant and minor changes in the sun.

They found that their model of weak changes in the sun gave the best correlation with temperature records, indicating that solar activity has had a minimal impact on temperature in the past millennium.

The study, published in Nature GeoScience, was supported by the Natural Environment Research Council.

“Until now, the influence of the sun on past climate has been poorly understood. We hope that our new discoveries will help improve our understanding of how temperatures have changed over the past few centuries, and improve predictions for how they might develop in future. Links between the sun and anomalously cold winters in the UK are still being explored.”

Dr Andrew Schurer
School of GeoSciences

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Kool Image Spring Fling: Sun Emits a Mid-Level Flare

     
  Kool Image

Solar Flare

Spring Fling: Sun Emits a Mid-Level Flare

 
 

Scientists produce some amazing images while performing their research. Astronomers are no different. An April 11, 2013 solar flair provided astronomers the opportunity to track the sun’s solar cycle.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel. This disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

The flare’s coronal mass ejection (CME), another solar phenomenon that can send billions of tons of solar particles into space, reached Earth one day later producing a temporary radio blackout.

It also produced the incredible image that is today’s cool image. Available as a 16″ X 20″ poster at our store.

Credit: NASA/SDO

 


 

Kool Image Barred Spiral Galaxy NGC 1073

     
  Kool Image

Barred Spiral Galaxy NGC 1073

Barred Spiral Galaxy NGC 1073

 
 

The NASA/ESA Hubble Space Telescope’s picture of the barred spiral galaxy NGC 1073, which is found in the constellation of Cetus (The Sea Monster). Our own galaxy, the Milky Way, is a similar barred spiral, and the study of galaxies such as NGC 1073 helps astronomers learn more about our celestial home.

Credit: NASA/ESA/Hubble Space Telescope

Available as a 20×16 inch poster at Barred Spiral Galaxy NGC 1073
Visit Hubble to discover more information.

 

Kool Image Sunspot Loops in Ultraviolet

     
  Kool Image

Sunspot Loops in Ultraviolet

Sunspot Loops in Ultraviolet

 
 

Explanation: It was a quiet day on the Sun. The above image shows, however, that even during off days the Sun’s surface is a busy place. Shown in ultraviolet light, the relatively cool dark regions have temperatures of thousands of degrees Celsius. Large sunspot group AR 9169 from the last solar cycle is visible as the bright area near the horizon. The bright glowing gas flowing around the sunspots has a temperature of over one million degrees Celsius. The reason for the high temperatures is unknown but thought to be related to the rapidly changing magnetic field loops that channel solar plasma. Large sunspot group AR 9169 moved across the Sun during 2000 September and decayed in a few weeks.

Credit: NASA/Trace Project
More information: The Transition Region and Coronal Explorer Mission