Sunday 2 October 2011

Speed-of-light results under scrutiny at Cern

Enormous underground detectors are needed to catch neutrinos, that are so elusive as to be dubbed "ghost particles"

Source: BBC





A meeting at Cern, the world's largest physics lab, has addressed results that suggest subatomic particles have gone faster than the speed of light.
The team has published its work so other scientists can determine if the approach contains any mistakes.
If it does not, one of the pillars of modern science may come tumbling down.
Antonio Ereditato added "words of caution" to his Cern presentation because of the "potentially great impact on physics" of the result.
The speed of light is widely held to be the Universe's ultimate speed limit, and much of modern physics - as laid out in part by Albert Einstein in his theory of special relativity - depends on the idea that nothing can exceed it.

Thousands of experiments have been undertaken to measure it ever more precisely, and no result has ever spotted a particle breaking the limit.
"We tried to find all possible explanations for this," the report's author Antonio Ereditato of the Opera collaboration told BBC News on Thursday evening.
"We wanted to find a mistake - trivial mistakes, more complicated mistakes, or nasty effects - and we didn't.
"When you don't find anything, then you say 'well, now I'm forced to go out and ask the community to scrutinise this'."
Friday's meeting was designed to begin this process, with hopes that other scientists will find inconsistencies in the measurements and, hopefully, repeat the experiment elsewhere.
"Despite the large [statistical] significance of this measurement that you have seen and the stability of the analysis, since it has a potentially great impact on physics, this motivates the continuation of our studies in order to find still-unknown systematic effects," Dr Ereditato told the meeting.
"We look forward to independent measurement from other experiments."

The Ten Commandments for Amateur Astronomers


 Sourced from October Canopus, Newsletter - ASSA Johannesburg Centre

  • Articles about the Bloemfontein visit in Canopus.

Submitted by Annelie Hoberg; Source: www.physlink.com, Anonymous

1. Thou shalt have no white light before thee, behind thee, or to the side of thee whilst sharing the night sky with thy fellow stargazers.
2. Thou shalt not love thy telescope more than thy spouse or thy children; as much as, maybe, but not more.
3. Thou shalt not covet thy neighbour's telescope, unless it exceeds in aperture or electronics twice that of thy wildest dreams.
4. Thou shalt not read "Astronomy" or "Sky & Telescope" on company time, for thine employer makes it possible to continue thine astronomical hobby.
5. Thou shalt have at least two telescopes so as to keep thy spouse interested when the same accompanies thee under the night sky or on eclipse expeditions to strange lands where exotic wild animals doth roam freely.
6. Thou shalt not allow either thy sons or thy daughters to get married during the Holy Days of Starfest.
7. Thou shalt not reveal to thy spouse the true cost of thy telescope collection; only the individual components and that shall be done with great infrequency.
8. Thou shalt not buy thy spouse any lenses, filters, dew shields, maps, charts, or any other necessities for Christmas, anniversaries, or birthdays unless thy spouse needs them for their own telescope.
9. Thou shalt not deceive thy spouse into thinking that ye are taking them for a romantic Saturday night drive when indeed thou art heading for a dark sky site.
10. Thou shalt not store thy telescope in thy living room, dining room, or bedroom, lest thou be sleeping with it full time.

Neville Young's book "Astronomy - Yes You Can"




New book - by Neville Young This composite photograph shows Fred Oosthuizen with the Stevick-Paul telescope that he built and mounted inside his observatory on the roof of his house. The photograph is being included in Neville Young's book "Astronomy - Yes You Can" which will reach the bookshops in March next year. Neville is a former chairman of the Pretoria Centre and is still a member of it. 

The book is also being translated into Afrikaans by Bosman Olivier, a committee member of the Pretoria Centre. The book is intended to interest the layman in astronomy particularly and in science generally, but has been received with great interest by the experienced amateur Michael Poll and the professional Barbara Cunow, who are helping Neville to ensure that the content of the book will be accurate. 

Friday 9 September 2011

NASA’s Cassini orbiter snaps unbelievable picture of Saturn

Click to enlarge

Science fiction movies have spoiled us on high definition views of our planetary neighbors, but real-life photographs with equal jaw-dropping potential are exceedingly rare. That's what makes NASA's awe-inspiring snapshot of Saturn (hi-res version here) such a stunning piece of eye candy.

Taken by NASA's Cassini robotic orbiter, the shot was captured from the dark side of Saturn as the Sun's bright rays illuminated every piece of dust and debris circling the planet. Cassini has offered astronomers a never-before-seen look at Saturn and revealed more information about the planet than any craft before it. The craft has taken so many pictures of the ringed wonder that they were recently made into a short flyby film that looks like it was created by George Lucas rather than a robotic space explorer.

The Cassini probe was launched in 1997 and took a further 7 years to reach Saturn's orbit. The total cost of its overarching objective of studying the ringed planet stands at a staggering $3.26 billion. However, the wealth of information it has wrought — including amazing pictures like the one above, and recordings of massive lightning storms on the planet — have already made it one of the best investments in space exploration. Hopefully Juno — which began a 5-year trek to Jupiter just last month — will bring us some equally stunning shots of Saturn's neighbor.
[Image credit: NASA]

Thursday 8 September 2011

Transit of Venus, 2012


The next transit of Venus will occur on June 5–June 6 in 2012, succeeding the previous transit on June 8, 2004. After 2012, the next transits of Venus will be in December 2117 and December 2125.

Monday 29 August 2011

Astronomers discover planet made of diamond


LONDON (Reuters) - Astronomers have spotted an exotic planet that seems to be made of diamond racing around a tiny star in our galactic backyard.
The new planet is far denser than any other known so far and consists largely of carbon. Because it is so dense, scientists calculate the carbon must be crystalline, so a large part of this strange world will effectively be diamond.
"The evolutionary history and amazing density of the planet all suggest it is comprised of carbon -- i.e. a massive diamond orbiting a neutron star every two hours in an orbit so tight it would fit inside our own Sun," said Matthew Bailes of Swinburne University of Technology in Melbourne.

Sunday 28 August 2011

Kollimasie werkswinkel


Met al die sirkeltjies en swart kolletjies in plek gaan jy net baie beter sien met jou teleskoop. By `n werkswinkel wat Thinus van der Merwe en Brett du Preez by die Boyden-sterrewag vir amateur sterrekundiges aangebied het, het lede geleer hoe om onder meer `n Cheshire kollimeerder te gebruik. 

Tipiese somer vlieswolke het die dieplugwaarneming in die wiele gery, maar daar was genoeg oop kolle om vinnig na Tuc 47 (NGC 104) en ook  `n paar ander voorwerpe te kyk.

Komeet C/2009 P1 (Garradd) in Sagitta was ook op die spyskaart en is en Wessel du Preez van Senekal het dit vinnig met sy nuwe 10" Skywatcher opgespoor. Net so links onder M71 (sterbondel).

  • Vroeër die middag het James Ross gehelp om al die spieël wat geslyp word se randjies te "bevel". Hy en Thinus het ook geloer of almal nog op die regte spoor is met die harde werk.

Saturday 30 July 2011

2012 Karoo-sterrefees

Die Sterrefees by Kambro Padstal by Britstown is in Weg, die reistydskrif aangekondig.
  • Kambro padstal was een van die naaswenners in Weg se kompetisie vir padstalle in Suid-Afrika.
  • 21 - 25 Maart 2012

Gerrit Penning en Pieter Pieterse maak reg vir die nag se waarnemings by Britstown tydens die 2011 sterrefees.
KAROO STARPARTY 2012

The ASSA Pretoria Centre is continuing the annual National Karoo Starparty which was started in
2009 at the Kambro Padstal, about 20 km north of Britstown in the Karoo, next to the N12 National Road. This event is intended to be a get-together for friends that want to enjoy the beautiful Karoo sky and there are no scheduled events, talks or workshops – we go there simply to enjoy the company of fellow stargazers and the legendary Karoo sky. 

The date for the 2012 Starparty is scheduled for the week-end of 21 March 2012. That is Wednesday 21 to Sunday 25 March 2012.

- Wednesday 12 March is a National Holiday. Please book early to avoid dissappointment! 

There is also accommodation available in Britstown at the Karoo Country Inn.

See http://www.kambroaccom.co.za or phone Wilma Strauss at 0833056668 for details of the site and to make a booking.

- Kambro Padstal by Britstown   GPS S30°-25-00.3 E23°-33-56.1

Thursday 28 July 2011

A Southern Comet on its way to us

 Copyright © 1995 by Tim Puckett


This image was taken by Tim Puckett (Villa Rica, Georgia, USA) on 1995 December 28.99, using a 0.30-m f/7 Meade LX-200 and an SBIG ST-6 CCD camera. It is a 300-second exposure.

16 August 2011: Closest approach of the brightest comet of the year
Comet: 45P/Honda-Mrkos-Pajdušáková
Visible: August until September, fading in October
Magnitude: 6
Finder charts: Sky Guide (pg 31)

 45P/Honda-Mrkos-Pajdušáková

 The comet Honda-Mrkos-Pajdusakova is expected to brighten rapidly in August as it passes to the south of the Earth. It will be observable from the southern hemisphere for about 2 weeks before getting too close to the Sun.

At its closest the comet will be 0.060 AU from the Earth, that is about 9 million kilometers away. While this is close for a comet, it is still about 24 times the distance of the moon. When it is first at magnitude 10, on the evening of August 9/10 it will be visible from New Zealand throughout the night, setting only briefly during daylight hours. For the next few nights until August 16 it will be circumpolar although low in the sky in the evening. On the 17th it will set briefly in the evening to rise again about midnight.

Over the next few days, as the comet moves north it will rise after midnight so becoming a morning object. Its elongation from the Sun will decrease as the comet moves away from the Earth towards the Sun and it will rise later in the morning to become lost in the morning twilight by about August 23.

By mid September Honda-Mrkos-Pajdusakova will be an 8th magnitude object rising about 90 minutes before the Sun into the dawn sky. The comet will then be slow moving in Leo, a few degrees from Regulus. By mid October it will have faded to magnitude 10.

45P/Honda-Mrkos-Pajdušáková is a periodic comet discovered by Minoru Honda December 3, 1948. The comet is named after Minoru Honda, Antonín Mrkos and Ludmila Pajdušáková. The orbit is elliptical with a period of 5.252 years. The comet nucleus is estimated to be 1.6 kilometers in diameter. (Information from Wikipedia.) 

45P/Honda-Mrkos-Pajdusakova
Perihelion: 2011 September 28
Maximum magnitude about 7 

 

Thursday 21 July 2011

Vaarwel aan NASA se ruimtependeltuig, Atlantis

Willie Koorts:

Wat ‘n fantastiese manier om die Pendeltuig program vaarwel te roep!  Na Oleg se voorspelling dat die twee ‘n paar minute uitmekaar sou wees en Rudie se opmerking op Facebook dat hulle verby die Suiderkruis gaan vlieg, het ek my foto beplan deur op een plek te konsentreer en agterna die fotos te kombineer.  Ek was so besig om te konsentreer op Atlantis, dat ek eers later besef het dat ISS so kort na dit volg, om die waarheid te sê, hulle was naby genoeg om in een veld te pas, maar ek moes deurdruk met my beplande foto.
Dit was wonderlik dat ons so goed geplaas was vir die swanesang, en boonop ook nog perfekte weer in die middel van die winter!