They were one of the world's most famous couples, who lived lives of power and glory - but who spent their last hours in despair and confusion. Now, more than 2,000 years since Antony and Cleopatra walked the earth, historians believe they may finally have solved the riddle of their last hours together.

A team of Greek marine archaeologists who have spent years conducting underwater excavations off the coast of Alexandria in Egypt have unearthed a giant granite threshold to a door that they believe was once the entrance to a magnificent mausoleum that Cleopatra VII, queen of the Egyptians, had built for herself shortly before her death.

They believe the 15-tonne antiquity would have held a seven metre-high door so heavy that it would have prevented the queen from consoling her Roman lover before he died, reputedly in 30BC.

"As soon as I saw it, I thought we are in the presence of a very special piece of a very special door," Harry Tzalas, the historian who heads the Greek mission, said. "There was no way that such a heavy piece, with fittings for double hinges and double doors, could have moved with the waves so there was no doubt in my mind that it belonged to the mausoleum. Like Macedonian tomb doors, when it closed, it closed for good."

Ancient rock-cut sculptures of the Buddha, resembling the Bamiyan Buddhas of Afghanistan, have been discovered in the Zanskar area in Ladakh region.

The discovery of the 1,400-year-old sculptures was made by the archives, archaeology and museums department of Jammu and Kashmir, an official said Sunday.

The Bamiyan Buddhas were destroyed by the Taliban.

The discovery has delighted archaeologists who believe the site in Kargil district could prove a tourist attraction.

The discovery is being publicised to get tourists, especially from Japan and Taiwan to the area. Kargil is 220 km north of Srinagar.

2009 is ending with a flurry of sunspots. The latest is sunspot 1039, which formed yesterday and is now crackling with low-level solar flares. Cai-Uso Wohler sends this picture of a B-class eruption from his backyard observatory in Bispingen, Germany:

So far, 65% of the days in December have brought sunspots--a sharp increase in percentages compared to earlier months of 2009 when sunspots were surpassingly rare. All six of December's sunspot groups have been members of new Solar Cycle 24. These numbers could herald the sun's awakening from the deepest solar minimum in nearly a century and a livelier sun in 2010. Stay tuned.

An Aboriginal dreaming story about a star crashing to Earth with a noise like thunder has led to the discovery of an ancient meteorite crater in central Australia.

A Sydney astronomer, Duane Hamacher, found the bowl-shaped crater in Palm Valley, about 130 kilometres south-west of Alice Springs, by searching on Google Earth.

He was inspired to look there after learning of traditional stories told by the local Arrernte people about a star that had fallen into a waterhole called Puka in the valley.

Mr Hamacher, a PhD candidate at Macquarie University, said that reality matching the Dreaming story could be a case of pure chance.

''But if so, it's an incredible coincidence,'' he said.

He is part of a team, led by a CSIRO astronomer, Ray Norris, that is exploring the possibility that Aborigines were the world's first astronomers.

Traditional Aboriginal wisdom about the heavens was impressive, Mr Hamacher said.

The world's biggest experiment is primed to answer one of the universe's biggest questions: what is the origin of mass? But an unexpected particle could yet steal the show.

In CERN's 27-kilometre tunnel near Geneva, Switzerland, the Large Hadron Collider will start smashing high-energy protons head-on in 2010. The shrapnel is expected to reveal the presence of the one missing member of the tribe of particles predicted by the standard model of physics: the Higgs boson, which is thought to endow elementary particles with mass. But the Higgs is unlikely to emerge during the year, as its telltale traces will be hard to spot amidst the complex debris left by the proton collisions.

Instead a different particle might hog the headlines: the neutralino. No one has ever seen one, but it is predicted by the theory of supersymmetry, which fixes many problems that plague the standard model. Supersymmetry doubles the number of elementary particles, adding one heavier super-partner for each standard-model particle.

Captain Nemo had it easy. When robotic submarines are sent 6000 metres to the bottom of an ocean-ridge rift in March, they will face furiously hot temperatures, pressure that gives oil the consistency of treacle, and rugged cliffs that plunge into the abyss. The pay-off, for an international collaboration of researchers called InterRidge, should be an insight into an unexplored world.

The Cayman trough is a 100-kilometre-long rift in the seabed between Jamaica and the Cayman Islands where the ocean floor is slowly pulling apart and new lava seeps up to fill the gap - a so-called ocean ridge. Such ridges are home to hydrothermal vents, and while vents at 3800 metres below the surface have been explored before, InterRidge plans to visit some of the world's deepest, which lie around 6000 metres down. At this depth, water doesn't boil until it reaches 500 °C.

The human brain works at a far higher level of complexity than previously thought. What has been given little attention up to now in the information processing of neuronal circuits has been the time factor. "Liquid computing" -- a new theory about how these complex networks of nerve cells actually work from computer scientists at Graz University of Technology -- has just passed its first test.

An interdisciplinary co-operation with neuroscientists from the Max-Planck Institute (MPI) for Brain Research in Frankfurt managed to show that early processing stages in the brain pool information over a longer period. For the evaluation of the experiments, the researchers also had to crack the neuronal code. The scientists published the new findings of their research work, which is funded by the Austrian Science Fund FWF in Austria, in the current edition of PLoS Biology.

The idea that the brain processes information step by step appears out of date. "The human brain does not work on the principle of the assembly line. In processing information, it is possible that time is treated much more flexibly than previously thought," explained Wolfgang Maass, head of the Institute for Theoretical Computer Science at Graz University of Technology. Like waves on a pool

The "magnetically best shielded room on earth" has the size of an apartment block and is located on the site of the Physikalisch-Technische Bundesanstalt (PTB), Institute Berlin. Magnetic fields such as that of the earth are kept out here as effective as nowhere else. Such ideal conditions allow to measure the tiny magnetic fields of, e.g., the human heart.

This was the motivation for the American National Institute of Standards and Technology (NIST) to ask PTB to jointly test a newly developed optical magnetic field sensor. It is based on a physical principle very different from SQUIDs, which are usually applied for biomagnetic field measurements. The optical sensor does not need advanced cooling and has the size of a lump of sugar. A high-quality measurement of the human heart signal was demonstrated using this optical sensor. The sensor's suitability was thus proven for biomagnetic measurements in the picotesla range. In future magnetocardiographic measurement devices -- to be used as a supplement or an alternative to the ECG -- could become simpler and less expensive.

Up until now one had to cool as much as one could for biomagnetic measurements. This was necessary as SQUIDs, superconducting quantum interference devices, work optimally at -269 degrees Celsius and can only then fulfil their purpose of measuring tiny magnetic fields. SQUIDs are the best suited sensors to record the magnetic fields arising during the electrical activity of the human heart. A magnetocardiogram (MCG) can be compiled supplementing a conventional electrocardiogram (ECG). (The same applies to the magnetoencephalogram, MEG, which is a recording of the magnetic field of the brain.) Yet to use SQUIDs requires well-shielded rooms and complicated cooling systems. The latter might become obsolete in the future if the optical magnetometer developed by NIST continues to fulfil expectations.

Just in time for Christmas, archaeologists on Monday unveiled what may have been the home of one of Jesus' childhood neighbors. The humble dwelling is the first dating to the era of Jesus to be discovered in Nazareth, then a hamlet of around 50 impoverished Jewish families where Jesus spent his boyhood.

Archaeologists and present-day residents of Nazareth imagined Jesus as a youngster, playing with other children in the isolated village, not far from the spot where the Archangel Gabriel revealed to Mary that she would give birth to the boy.

Today the ornate Basilica of the Annunciation marks that spot, and Nazareth is the largest Arab city in northern Israel, with about 65,000 residents. Muslims now outnumber Christians two to one in the noisy, crowded city.

The archaeological find shows how different it was 2000 years ago: There were no Christians or Muslims, the Jewish Temple stood in Jerusalem and tiny Nazareth stood near a battleground between Roman rulers and Jewish guerrillas.

Scientists at UC Santa Barbara have made a major discovery in how the brain encodes memories. The finding, published in the December 24 issue of the journal Neuron, could eventually lead to the development of new drugs to aid memory.

The team of scientists is the first to uncover a central process in encoding memories that occurs at the level of the synapse, where neurons connect with each other.

"When we learn new things, when we store memories, there are a number of things that have to happen," said senior author Kenneth S. Kosik, co-director and Harriman Chair in Neuroscience Research, at UCSB's Neuroscience Research Institute. Kosik is a leading researcher in the area of Alzheimer's disease.

"One of the most important processes is that the synapses -- which cement those memories into place -- have to be strengthened," said Kosik. "In strengthening a synapse you build a connection, and certain synapses are encoding a memory. Those synapses have to be strengthened so that memory is in place and stays there. Strengthening synapses is a very important part of learning. What we have found appears to be one part of how that happens."