Sunday, 24 October 2010

University of Texas Students, Telescopes Help Discover Planets Around Elderly Binary Star

 The 2.1-meter (82-inch) Otto Struve Telescope at the University of Texas McDonald Observatory. Photo by Marty Harris/McDonald Observatory.


News Release: McDonald Observatory, The University of Texas, 21 October 2010
An international consortium of astronomers, including undergraduate and graduate
students at The University of Texas at Austin, have discovered a planetary system
consisting of at least two massive Jupiter-like planets orbiting the extremely close
binary star system NN Serpentis. The team used a wide variety of observations
taken over two decades from many telescopes, including two at The University of
Texas at Austin’s McDonald Observatory in West Texas.
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The results are published
online in the current edition of the journal Astronomy & Astrophysics.
Because of the disturbing effects of a binary star system’s gravity, astronomers
normally do not expect to find planets in such systems, but the research team was
able to use the eclipses of the stars as a precise clock whose irregularities could be
used to detect planets in orbit around the binary.

Multi-University Project to Study 'Dark Energy' Receives $8 Million from National Science Foundation

Video to watch
 

















News Release: McDonald Observatory, The University of Texas, 20 October 2010

A project to discover the nature of dark energy, a mysterious force causing the expansion of the universe to speed up, has received an $8 million grant from the National Science Foundation (NSF).
The funds will be split among The University of Texas at Austin ($3.6 million), Texas A&M University ($3.9 million) and Penn State University ($.5 million), to support their respective roles in the Hobby-Eberly Telescope Dark Energy Experiment, or HETDEX. The project will be carried out at The University of Texas at Austin’s McDonald Observatory in west Texas.
“HETDEX is one of our gems within the university,” said William Powers Jr., president of The University of Texas at Austin. “It’s one of the projects being done here today that will still be talked about in a hundred years, the way we now read about discoveries by Newton and Einstein. This NSF grant is strong confirmation of the project’s importance and our commitment to it.”

Feedback after Laser Workshop during ASSA Symposium in Pretoria

Pretoria Centre of the Astronomical Society of Southern Africa

Laser Safety

PROPOSED FEEDBACK TO ASSA NATIONAL BODY REGARDING LASER WORKSHOP DURING 2010 ASSA SYMPOSIUM

Background:
Regulation 1302 identifies visible lasers with an output power over 0.30µW as 'dangerous goods' under the HAZARDOUS SUBSTANCES ACT NO. 15 OF 1973
  1. Importers who import these devices must license the product at the Department of Health.
  2. Any person using a laser device with an output power of more than 5 mW has to register as a Laser Safety Officer (LSO) at the Department of Health.
  3. There is a general concern that laser pointers are used irresponsibly. This may increase the risk that green laser pointers be 'overregulated' by the Dept. of Health.
Delegates agree to the following:
  1. ASSA members are encouraged to register their unregistered laser pointers (It is currently free to do so)
  2. The organisers of events such as star parties, ScopeX, viewing evenings, etc, will be liable in accordance with the Occupational Health and Safety Act (Act 85 of 1993) for any incident during the event. The organisers therefore have to define the 'laser rules' for the event and act accordingly.
  3. The organisers have the right to confiscate (store in safe position) any non-compliant laser pointer used at the event.
  4. There is no requirement for anyone (except presenting astronomers) to use a laser pointer with an output of more than 5mW for astronomy purposes.
  5. Presenting astronomers (those who do astronomy presentations to groups of people) may justify the use of stronger laser pointers. Suggested laser output ranged from 10mW to 50mW. The delegates agree that 20mW should be suitable for most applications, but foresee applications for up to 50mW.
  6. Approved organisations should be identified (eg: ASSA branches; Universities; SAAO; SANParks; etc) These organisations should recommend applications for LSO's.
  7. The following 'safe practices' is a good starting point when presentations to groups are done:
    • Lasers should be used by knowledgeable astronomers under controlled circumstances:
    • Do not point at people, aircraft or animals
    • Keep suitable distance from audience
    • Warn the audience
    • Area should be clean of obstacles
    • Avoid pointing to surfaces that can give specular reflections
    • Minimise use (do not play)
    • Keep away from children
    • Do not use mechanisms that keeps the pointer switched on.
  8. The outcome should be posted on the website and comments requested.
Additional comments from discussions after the workshop:
  1. There was a notion that 'approved organisations' (ASSA; SAAO; Universities; etc) appoint personnel to train users of green laser pointers in the safe practices.
  2. Aspiring LSO's has to pass a laser safety test.
  3. ASSA should have a LASER safety section (to communicate with the DoH)

  • Example of a very comprehensive Laser Safety Manual.
  • Give feedback or leave a comment about the Green laser isssue
  • Read some of the feedback and comments.

Friday, 22 October 2010

Media release: South Africa's MeerKAT in high demand

22 October 2010
Five years before South Africa's MeerKAT telescope becomes operational, more than 43 000 hours of observing time (adding up to about five years) have already been allocated to radio astronomers from Africa and around the world, who have applied for time to do research with this unique and world-leading instrument. Surveys of radio pulsars and hydrogen gas in the deep universe came out on top in the first round of allocating MeerKAT's observing time. 

MeerKAT is South Africa's precursor telescope to the SKA (Square Kilometre Array) and will consist of 64 Gregorian offset dishes, each 13.5 m in diameter. A MeerKAT engineering test bed of seven dishes (KAT-7) is already complete on site in the Karoo region of South Africa's Northern Cape Province. 

Following an October 2009 invitation to the world's radio astronomers to apply for MeerKAT telescope time to perform large survey projects, 21 proposals, involving more than 500 astronomers from around the world (59 from Africa), were received. A Time Allocation Committee made up of local and international experts rated the proposals on the basis of scientific merit, technical and operational feasibility, the extent to which MeerKAT has a unique role for the proposed observations or is an essential component in a larger campaign, and the resources each group was prepared to bring to the project. 

The science objectives of the most highly rated projects also happen to be the prime science drivers for the first phase of the SKA telescope itself, confirming MeerKAT's designation as an SKA precursor instrument. Observing time has been allocated to:
  • Nearly 8 000 hours to a proposal to test Einstein's theory of gravity and investigate the physics of enigmatic neutron stars. This radio pulsar timing survey will be led by Professor Matthew Bailes at the Swinburne Centre for Astrophysics and Supercomputing in Australia.
  • Another 5 000 hours jointly to two proposals to survey the distant universe with MeerKAT. This ultra-deep survey of neutral hydrogen gas in the early universe will be led by Dr Sarah Blyth and Dr Benne Holwerda, both at the University of Cape Town in South Africa, in partnership with Dr Andrew Baker at Rutgers University in the US. The American team, involving several South African team members, called their proposal "LADUMA!" - an acronym for Looking at the Distant Universe with MeerKAT Array, but also a South African expression of delight when a goal is scored in football).
Eight other proposals were rated highly and have also been allocated time on the MeerKAT. They are:
  • MESMER: MeerKAT Search for Molecules in the Epoch of Re-ionisation, led by Dr Ian Heywood, University of Oxford in the UK - 6500 hours.
  • MeerKAT Absorption Line Survey, led by Dr Yashwant Gupta and Dr Raghunathan Srianand, both associated with the Giant Metrewave Radio Telescope in India - 4 000 hours.
  • MHONGOOSE: MeerKAT HI Observations of Nearby Galactic Objects: Observing Southern Emitters, led by Professor Erwin de Blok at the University of Cape Town in South Africa - 6 000 hours.
  • TRAPUM: Transients and Pulsars with MeerKAT, led jointly by Dr Benjamin Stappers at the Joddrell Bank Centre for Astrophysics, UK and Professor Michael Kramer at the Max Planck Institute for Radio Astronomy, Germany - 3 080 hours.
  • A MeerKAT HI Survey of the Fornax Cluster, led by Dr Paolo Serra at ASTRON, an astronomy research institute in The Netherlands - 2 450 hours.
  • MeerGAL: A MeerKAT High Frequency Galactic Plane Survey, led jointly by Dr Mark Thompson, University of Hertfordshire in the UK and Dr Sharmilla Goedhart of the South African MeerKAT team - 3 300 hours.
  • MIGHTEE: MeerKAT International GigaHertz Tiered Extragalactic Exploration Survey, led by Dr Kurt van der Heyden, University of Cape Town with Dr Matt Jarvis who represents both the University of the Western Cape in South Africa and the University of Hertfordshire in the UK - 1 950 hours.
  • ThunderKAT: The Hunt for Dynamic and Explosive Radio Transients with MeerKAT, led by Professor Patrick Woudt, University of Cape Town in South Africa and Professor Rob Fender at the University of Southampton in the UK - 3 000 hours.
"In addition to these ten high priority surveys, there is a strong case for MeerKAT to participate in the world-wide VLBI (very long baseline interferometry) observations, which use telescopes all around the world, working together. "We will ensure that MeerKAT becomes affiliated to international VLBI networks and will commit time to these observations," explains Dr Bernie Fanaroff, Director of the SKA South Africa Project. 

"The Hartebeesthoek Radio Astronomy Observatory (HartRAO) in South Africa will lead the VLBI collaboration with all major radio astronomy observatories around the world," adds Professor Roy Booth, Associate Director: Science and Operations at the SKA South Africa Project. "MeerKAT will add considerably to the sensitivity of the global VLBI network." 

"We would also like to explore the potential for SETI (search for extraterrestrial intelligence) and for collaboration with NASA on downloading information from their space probes sent to other planets," Dr Fanaroff adds as another key science objective for MeerKAT.

The teams who have submitted the successful proposals will be invited to work with the MeerKAT team throughout the design phase of the telescope, and to become involved in the project's human capacity building programme. 

Thursday, 21 October 2010

Newly discovered massive galaxy cluster wins heavyweight title


Astronomers using the South Pole Telescope report that they have discovered the most massive galaxy cluster yet seen at a distance of 7 billion light-years. The cluster (designated SPT-CL J0546-5345) weighs in at around 800 trillion Suns, and holds hundreds of galaxies.

“This galaxy cluster wins the heavyweight title. It’s among the most massive clusters ever found at this distance,” said Mark Brodwin, a Smithsonian astronomer at the Harvard-Smithsonian Center for Astrophysics. Brodwin is first author on the paper announcing the discovery, which appeared in the Astrophysical Journal.

Redshift measures how light from a distant object has been stretched by the universe’s expansion. Located in the southern constellation Pictor (the Painter), the cluster has a redshift of z=1.07. This puts it at a distance of about 7 billion light-years, meaning we see it as it appeared 7 billion years ago, when the universe was half as old as now and our solar system didn’t exist yet.

...read more

Space Photos This Week: Cosmic Spiral, Eclipsed Sun, More...

Galaxy is most distant object yet

The faintest of faint dots - a signal from the edge of the observable Univers. A tiny faint dot in a Hubble picture has been confirmed as the most distant galaxy ever detected in the Universe.
This collection of stars is so far away its light has taken more than 13 billion years to arrive at Earth. 

Astronomers used the Very Large Telescope in Chile to follow up the Hubble observation and make the necessary detailed measurements. 

They tell the journal Nature that we are seeing the galaxy as it was just 600 million years after the Big Bang.

...read more

In pictures: Wildlife Photographer of the Year 2010



A stunning silhouette of active leafcutter ants in Costa Rica wins the Wildlife Photographer of the Year award. Earth News

Source: BBC News

New International Standard For Spacecraft Docking


The initial IDSS definition document will be released into the public domain on 25 October. It will contain a preliminary description of the physical features and design loads of the standard docking interface.

by Staff Writers Paris, France (ESA) Oct 21, 2010 SpaceTravel.com
Partners in the International Space Station programme have agreed on a new standard for docking systems, which will be capable also of implementing berthing. The agreement allows a range of compatible, but not necessarily identical, mechanisms for spacecraft docking. A first agreed version of the Interface Definition Document will be released on 25 October.

Wednesday, 20 October 2010

Donderdagaand is dit Sterre en Planete op RSG

Maak `n knoop iewers!


Donderdagaand om 20:30 is dit die Sterre en Planete uitsending op RSG.

Los bietjie die Televisie en trek die radio nader.

En as jy regtig nie kan luister nie, kan jy gerus die MP3 aflaai en later na die uitsending luister.