Our summer almanac 03.09.2010 – 09.09.2010

September 4 is the beginning of the Jain festival of Paryushana
The most important Jain festival, it consists of eight (Swetambara) or ten (Digambara) days of intensive fasting and repentance. Paryushan means, literally, “abiding” or “coming together”. It is also a time when the laity take on vows of study and fasting with a spiritual intensity similar to temporary monasticism. A time of reflection, Paryusana comes at the time when the wandering monks take up temporary residence for four months of the monsoon. In popular terminology, this stay is termed chaturmasa because the rainy season is regarded to be about four months.

Jainism is an ancient religion of India that prescribes a path of non-violence towards all living beings. In all, there are approximately 35,000 Jains living in Britain, and there are temples and community centres all over the UK – several in London, and centres in Leicester, Birmingham, Manchester, Leeds and where the community does not have a base, they hire a local school or community hall to celebrate.

This converted congregational chapel is now a Jain Centre in Oxford

Mahavira, or “Great Hero”, traditionally 599 – 527 BCE, is the name most commonly used to refer to the Indian sage Vardhamana (Sanskrit: वर्धमान “increasing”) who established what are today considered to be the central tenets of Jainism.

Asteroids pass the Earth

This week, according to NASA, two asteroids, several meters in diameter and in unrelated orbits, will pass within the moon’s distance of Earth on Wednesday, Sept. 8.

Both asteroids should be observable near closest approach to Earth with moderate-sized amateur telescopes. Neither of these objects has a chance of hitting Earth.

Heavy Stuff
At this time of year the constellation Cygnus the Swan is still clearly visible in the night sky before midnight. There is a star in this part of the sky called Cygnus X-1, an X-ray star where some very strange things are happening.

The story of its discovery begins with the search for neutron stars. In the story of our Universe that we call the Timeline section, we looked at Type II Supernovae explosions in Astrofact 26. We were interested in the way this explosive death of a star produces the everyday stuff that we are made of. As Carl Sagan used to say “we are star stuff”.

Neutron stars are what is left behind after the explosive end of huge bright stars. Neutron stars are made from the collapsing material of these huge dying stars. This material is mostly made of neutrons and is matter compacted to an extreme density. Imagine a star like our Sun with all its matter compressed like a neutron star, it could turn out to be an object less than 6 miles across. A cubic centimetre of a neutron star would weigh about 100 million tonnes.

It was in the 1930’s, just after physicists had discovered neutrons, that astronomers wondered about the possibility of the existence of neutron stars. In 1934, the astronomers Walter Baade and Fritz Zwicky thought that the only way to explain the energy output of a supernova was through the collapse of an ordinary star into a neutron star. It was only in the 1960’s with the discovery of ‘pulsars’, stars that produce rapid blips of noise on radio telescopes, that astronomers realized that they may have found rapidly spinning neutron stars.

It was in 1937 that Grote Reber, an amateur astronomer in the United States built the first radio telescope. A radio telescope detects radio waves from space, signals emitted from stars, galaxies, nebulae and other astronomical objects. In 1967 a team of radio astronomers at the University of Cambridge had built a new kind of radio telescope to look at flickering in the radio output of quasars, a term that stands for quasi-stellar radio sources. What they found were pulsars. A thousand pulsars have been found so far. Pulsars are neutron stars spinning incredibly fast with the slowest spinning round about once every 4 seconds, and the fastest turning on its axis 600 times a second. The radio noise, or signal they send out into space and is received on Earth by radio telescopes, is produced by their incredibly powerful magnetic fields, 1000 million times as strong as the magnetic field of the Earth.

The proof of the existence of neutron stars meant that another, even stranger idea would have to be explored, the possibility of ‘black holes’.

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