Robyn Adderly
Hubble captures birthday bubble
This vivid new portrait captures in stunning clarity what looks like a gigantic cosmic soap bubble. The Bubble Nebula also known as NGC 7635, lies 8,000 light-years away in the constellation Cassiopeia, and is, in fact a cloud of gas and dust illuminated by the brilliant star within it. This new Hubble Space Telescope image has been released to celebrate Hubble’s 26th year in orbit.
The complete view of the Bubble Nebula allows us to fully appreciate the almost perfectly symmetrical shell which gives the nebula its name. This shell is the result of a powerful flow of gas – known as a stellar wind – from the bright star visible just to the left of centre in this image. The star, SAO 20575, is between 10 and 20 times the mass of the Sun and the pressure created by its stellar wind forces the surrounding interstellar material outwards into this bubble-like form.
The giant molecular cloud that surrounds the star – glowing in the star’s intense ultraviolet radiation – tries to stop the expansion of the bubble. However, although the sphere already measures around 10 light-years in diameter, it is still growing, owing to the constant pressure of the stellar wind – currently at more than 100,000 kilometres per hour!
As always, and 26 years on, Hubble gives us much more than a pretty picture.
High-power solar electric propulsion test
A prototype 13-kilowatt Hall thruster is tested at NASA's Glenn Research Centre in Cleveland, Ohio, demonstrating technology readiness needed for industry to develop high-power solar electric propulsion into a flight-qualified system.
An advanced electric propulsion system could potentially increase spaceflight transportation fuel efficiency by 10 times over current chemical propulsion technology and more than double thrust capability compared to current electric propulsion technology.
The next step will be to demonstrate this new electric propulsion system in space.
It will, engineers hope, help a variety of deep space human and robotic exploration missions, such as the NASA’s Asteroid Redirect Mission (ARM), as well as private commercial space missions.
Untangling webs inside our brain
Because billions of neurons are packed into our brain, the neuronal circuits that are responsible for controlling our behaviours are by necessity highly intermingled. This tangled web makes it complicated for scientists to determine exactly what various circuits do.
Now, using two laboratory techniques pioneered in part at Caltech, researchers have mapped out the pathways of a set of neurons responsible for the kinds of motor impairments – such as difficulty walking – found in patients with Parkinson's disease.
Different colours in this image represent pathways involving different cells that instruct diverse behaviours. The Caltech team could extract specific pathways for locomotion and reward. The work was published in the journal Neuron this week.
Robot serves customers in a Shenyang restaurant
A robot delivers meals for customers at a restaurant in Shenyang, Liaoning Province of China. The robot, 140 centimetres tall and weighing 60 kilograms, says phrases such as 'hello', 'please', 'see you again' and so on.
One battery charge powers the robot for an eight-hour shift. A robot will cost about 60,000 Yuan (US$9,200).
Earthquakes strike Ecuador and Japan
A magnitude-7.8 earthquake struck Ecuador’s coast on 16 April, killing at least 570 people. It was the country’s most powerful quake since 1979 and devastated towns near the coast.
Separately, a series of shallow earthquakes shook Japan’s Kyushu Island last week, culminating in a magnitude-7 tremor on 16 April that killed at least 42 people and caused 180,000 to be evacuated.
