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In the same way that earthquakes can reveal hidden secrets about our planet, astronomers are hoping that 'starquakes' will unravel the mysteries surrounding stars.

These are huge pulses that travel through stars, and literally rip them apart, sending out a massive amount of energy through space in a short amount of time.

The phenomenon takes place in neutron stars, which contain the equivalent mass of half-a-million Earths into a sphere about 12 miles (19.3km) across - roughly the length of Manhattan Island in New York.

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A rupture in the crust of a highly magnetised neutron star, shown here in an artist's rendering, can trigger high-energy eruptions. Fermi observations of these blasts include information on how the star's surface vibrates

Hints of this rare event were picked up in 2009 during a rapid-fire series of pulses on an extremely magnetised neutron star, also known as a magnetar.

Now astronomers have again studied this data and confirmed underlying signals that might indicate a starquake on this magnetar that caused it to 'ring like a bell.'

'Fermi's Gamma-ray Burst Monitor (GBM) has captured the same evidence from smaller and much more frequent eruptions called bursts,' said Anna Watts, an astrophysicist at the University of Amsterdam in the Netherlands

'[This opens] up the potential for a wealth of new data to help us understand how neutron stars are put together.'

NASA satellite finds hints of starquakes in magnetar 'storm'

The starquakes were found in the midst of SGR J1550-5418's 2009 storm after Swift's X-Ray Telescope captured an expanding halo produced by the magnetar's brightest bursts.

The rings formed as X-rays from the brightest bursts scattered off of intervening dust clouds.

While typical neutron stars have magnetic fields trillions of times stronger than Earth's, the eruptive activity observed from magnetars requires fields 1,000 times stronger still.

Because a neutron star's solid crust is locked to its intense magnetic field, a disruption of one immediately affects the other.

The changes trigger a sudden release of stored energy via powerful bursts that vibrate the crust, a motion that becomes imprinted on the burst's gamma-ray and X-ray signals.

It takes an incredible amount of energy to convulse a neutron star. The closest comparison on Earth is the 9.5-magnitude Chilean earthquake of 1960, which ranks as the most powerful ever recorded on the standard scale used by seismologists.

On that scale, said Professor Watts, a starquake associated with a magnetar giant flare would reach magnitude 23.

The 2009 burst storm came from SGR J1550−5418, an object discovered by Nasa's Einstein Observatory, which operated from 1978 to 1981.

Located about 15,000 light-years away in the constellation Norma, the magnetar was quiet until October 2008, when it entered a period of eruptive activity that ended in April 2009.

At times, the object produced hundreds of bursts in as little as 20 minutes, and the most intense explosions emitted more total energy than the sun does in 20 years.

High-energy instruments on many spacecraft, including Nasa's Swift and Rossi X-ray Timing Explorer, detected hundreds of gamma-ray and X-ray blasts.

Pictured is Nasa's Fermi Gamma-ray Space Telescope,being readied for launch. The Gamma-ray Burst Monitor (GBM) in the centre is an array of 14 crystal detectors sensitive to short-lived gamma-ray blasts

Speaking at the Fifth Fermi International Symposium in Nagoya, Japan, Professor Watts said the new study examined 263 individual bursts detected by Fermi's GBM and confirms vibrations in the frequency ranges previously seen in giant flares.

'We think these are likely twisting oscillations of the star where the crust and the core, bound by the super-strong magnetic field, are vibrating together,' she explained.

'We also found, in a single burst, an oscillation at a frequency never seen before and which we still do not understand.'

Knowing more about how bursts shake up these stars will give theorists an important new window into understanding their internal structure.

'Right now,' added Professor Watts, 'we are waiting for more bursts - and if we're lucky, a giant flare - to take advantage of GBM's excellent capabilities.'

Hints of a starquake were picked up in 2009 during a rapid-fire series of pulses on an extremely magnetised neutron star, also known as a magnetar (artist's impression pictured)