Rocks around the clock: asteroids pound tiny star

Feb 19, 2014
An artist's impression of an asteroid breaking up. Credit: NASA/JPL-Caltech

(Phys.org) —Scientists using CSIRO's Parkes telescope and another telescope in South Africa have found evidence that a tiny star called PSR J0738-4042 is being pounded by asteroids—large lumps of rock from space.

"One of these rocks seems to have had a mass of about a billion tonnes," CSIRO astronomer and member of the research team Dr Ryan Shannon said.

PSR J0738-4042 lies 37,000 light-years from Earth in the constellation of Puppis.

The environment around this star is especially harsh, full of radiation and violent winds of particles.

"If a large rocky object can form here, planets could form around any star. That's exciting," Dr Shannon said.

The star is a special one, a 'pulsar' that emits a beam of radio waves.

As the star spins, its radio beam flashes over Earth again and again with the regularity of a clock.

In 2008 Dr Shannon and a colleague predicted how an infalling asteroid would affect a pulsar. It would, they said, alter the slowing of the pulsar's spin rate and the shape of the radio pulse that we see on Earth.

"That is exactly what we see in this case," Dr Shannon said.

"We think the pulsar's radio beam zaps the , vaporising it. But the vaporised particles are electrically charged and they slightly alter the process that creates the pulsar's beam."

Asteroids around a pulsar could be created by the exploding star that formed the pulsar itself, the scientists say.

The material blasted out from the explosion could fall back towards the forming pulsar, forming a disk of debris.

Astronomers have found a dust disk around another pulsar called J0146+61.

"This sort of dust disk could provide the 'seeds' that grow into larger asteroids," said Mr Paul Brook, a PhD student co-supervised by the University of Oxford and CSIRO who led the study of PSR J0738-4042.

In 1992 two planet-sized objects were found around a called PSR 1257+12. But these were probably formed by a different mechanism, the astronomers say.

The new study has been published as a paper in The Astrophysical Journal Letters, a leading journal of astronomical research: Evidence of an asteroid encountering a pulsar.

Explore further: IGR J11014-6103: Chandra sees runaway pulsar firing an extraordinary jet

More information: "Evidence of an Asteroid Encountering a Pulsar," P. R. Brook et al., 2014 ApJ, 780, L31. dx.doi.org/10.1088/2041-8205/780/2/L31

add to favorites email to friend print save as pdf

Related Stories

A spinning neutron star is tied to a mysterious tail

Aug 18, 2011

(PhysOrg.com) -- A spinning neutron star is tied to a mysterious tail -- or so it seems. Astronomers using NASA's Chandra X-ray Observatory found that this pulsar, known as PSR J0357+3205 (or PSR J0357 for ...

Dead star and distant black holes dazzle in X-rays

Jan 09, 2014

(Phys.org) —Two new views from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, showcase the telescope's talent for spying objects near and far. One image shows the energized remains of a dead star, ...

A pulsar's mysterious tail

Jul 14, 2011

(PhysOrg.com) -- A spinning neutron star is tied to a mysterious tail -- or so it seems. Astronomers using NASA's Chandra X-ray Observatory have found that this pulsar, known as PSR J0357+3205 (or PSR J0357 ...

A strong magnetic field around the Milky Way's black hole

Aug 14, 2013

(Phys.org) —Astronomers have made an important measurement of the magnetic field emanating from a swirling disk of material surrounding the black hole at the center of our Milky Way Galaxy. The measurement, ...

Recommended for you

Image: Multicoloured view of supernova remnant

2 hours ago

Most celestial events unfold over thousands of years or more, making it impossible to follow their evolution on human timescales. Supernovas are notable exceptions, the powerful stellar explosions that make ...

Ultra-luminous X-ray sources in starburst galaxies

2 hours ago

Ultra-luminous X-ray sources (ULXs) are point sources in the sky that are so bright in X-rays that each emits more radiation than a million suns emit at all wavelengths. ULXs are rare. Most galaxies (including ...

When a bright light fades

2 hours ago

Astronomer Charles Telesco is primarily interested in the creation of planets and stars. So, when the University of Florida's giant telescope was pointed at a star undergoing a magnificent and explosive death, ...

Image: Horsehead nebula viewed in infrared

3 hours ago

Sometimes a horse of a different color hardly seems to be a horse at all, as, for example, in this newly released image from NASA's Spitzer Space Telescope. The famous Horsehead nebula makes a ghostly appearance ...

The Milky Way's new neighbour

3 hours ago

The Milky Way, the galaxy we live in, is part of a cluster of more than 50 galaxies that make up the 'Local Group', a collection that includes the famous Andromeda galaxy and many other far smaller objects. ...

Image: Hubble sweeps a messy star factory

3 hours ago

This sprinkle of cosmic glitter is a blue compact dwarf galaxy known as Markarian 209. Galaxies of this type are blue-hued, compact in size, gas-rich, and low in heavy elements. They are often used by astronomers ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.