One of the most important but least understood processes in astronomy is accretion, where the mass of an object grows by gravitationally collecting material from nearby. Now an international team has discovered that that the process by which astronomical objects grow is fundamentally the same, regardless of the type, mass or size of the object.
Phenomenally durable crystals called zircons are used to date some of the earliest and most dramatic cataclysms of the solar system, such as the late heavy bombardment that created hellish surface conditions on the young Earth and Moon about 4 billion years ago. Now a study of zircons from a gigantic meteorite impact in South Africa casts doubt on the methods used to date lunar impacts.
According to observations from the Tihany Magnetic Observatory in Hungary, the indices used by scientists to assess the Sun’s geomagnetic perturbations to the Earth are unable to detect some of these events, which could put both power supply and communication networks at risk. The Tihany Magnetic Observatory registered a solar storm similar to the largest one ever recorded while other observatories were completely unaware of the event.
It seems that the more we see of Pluto, the more fascinating it gets. This latest image, from the heart of Pluto’s heart feature, shows the plains’ enigmatic cellular pattern as well as unusual clusters of small pits and troughs. Adding to the intrigue is that even at this resolution of 250 metres, no impact craters are seen, testifying to the region’s extreme geologic youth.
NASA’s Cassini spacecraft has begun returning its best-ever views of the northern extremes of Saturn’s icy, ocean-bearing moon Enceladus. Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but the new high-resolution Cassini images show a landscape of stark contrasts.
A giant mound near the Moon’s south pole appears to be a volcanic structure unlike any other found on the lunar surface, according to new research by Brown University geologists. The formation, known as Mafic Mound, stands about 800 metres tall and 75 kilometres (47 miles) across, smack in the middle of a giant impact crater known as the South Pole-Aitken Basin.
The New Horizons team described a wide range of findings about the Pluto system in its first research paper published today — just three months after NASA’s historic first exploration of the dwarf planet. New Horizons has revealed a degree of diversity and complexity on Pluto and its moons that few expected in the frigid outer reaches of the solar system.
In general, the larger a galaxy’s mass, the higher its rate of forming new stars. However, every now and then a galaxy will display a burst of newly-formed stars that shine brighter than the rest. Researchers using the Atacama Large Millimetre Array (ALMA) have found that galaxies forming stars at extreme rates 9 billion years ago were more efficient than average galaxies today.
We can’t see the wind, but we can learn about it by observing things that are being blown about. And by studying changes in a comet’s bright tail of gas and ions, scientists are on the trail to solving two big mysteries about the solar wind — the supersonic outflow of electrically charged gas from the Sun’s million-degree upper atmosphere, or corona.
Scientists using the NASA/ESA Hubble Space Telescope have produced new maps of Jupiter that show the continuing changes in its famous Great Red Spot. The images also reveal a rare wave structure in the planet’s atmosphere that has not been seen for decades. This is the first in a series of annual portraits of the solar system’s outer planets which will help researchers study how they change over time.
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