Archive for the ‘Astronomy blog’ Category

The Karl G. Jansky Very Large Array (VLA) is located close to the town of Socorro, New Mexico and is perhaps best known as the radio telescope facility used by Jodie Foster in the movie ‘Contact’. There are 27 antennas on site, with each having a diameter of 25 metres, over 27 metres high and weighing 230 tons. All 27 antennas work as one telescope system and a central supercomputer combines the signals from each dish into one. They form a ‘Y’ shape and there are rail tracks along which the antennas can be moved, effectively zooming in or out to produce images of varying detail, depending on the requirements.

One of 27 radio telescopes at the VLA, New Mexico. Photo and copyright Melissa Hulbert ©, all rights reserved.

One of 27 radio telescopes at the VLA, New Mexico.
Photo and copyright Melissa Hulbert ©, all rights reserved.

There is a walking track outside with informative information about radio astronomy which takes you out to a nearby dish for a closer look. While there the dish was repositioned a few times and just watching this huge, 230 ton metal dish move with such precision to accurately pinpoint a specific target in the sky really enhanced what an amazing engineering feat these telescopes are.

Part of the VLA array, New Mexico. Photo and copyright Melissa Hulbert ©, all rights reserved.

Part of the VLA array, New Mexico.
Photo and copyright Melissa Hulbert ©, all rights reserved.

The Bracewell Radio Sundial named after Ronald N. Bracewell (an Australian) who worked on radar in WWII, afterwards developing many mathematical methods for creating images with radio telescopes and later helped adapt techniques of radio-astronomy to make CAT scans a reality.

This sundial is an amazing instrument, not only telling solar time but also having markers for solstices, equinoxes and three strong radio sources in the sky; Cygnus A, Cassiopeia A and Centaurus A. It is an interesting exercise to work out the sidereal time and see if any of these objects are above the horizon.

The Bracewell Sundial, VLA, New Mexico. Photo and copyright Melissa Hulbert ©, all rights reserved.

The Bracewell Sundial, VLA, New Mexico.
Photo and copyright Melissa Hulbert ©, all rights reserved.

 

The town that never was…

The Bradbury Science Museum in Los Alamos is a fascinating place to visit as it covers the history of the Los Alamos National Laboratory and the town’s initial formation around the Manhattan Project and the development of the atomic bomb by a group of scientists led by J. Robert Oppenheimer. Originally Los Alamos was ‘the town that never was’ as the Manhattan Project was so secret that officially the town did not exist. The town’s mail all went to PO Box 1663, Santa Fe, New Mexico, to keep its existence secret. The inhabitants of Santa Fe called the town ‘The Hill’ while the military called it ‘Project Y’.

This is a sensitive subject for many reasons and the Museum recognises this and has a public forum space where visitors are welcome to leave their thoughts and comments.

I found it interesting to learn more about the atomic physics and where this research has led us to in the present day. I was also interested to learn Robert Oppenheimer’s thoughts when the first atomic bomb detonated in the Trinity test in New Mexico: “Now I am become Death, the destroyer of worlds.” which he read and translated from the original Sanskrit text in a later interview. Regardless of your thoughts on this subject, the Museum is worth a visit, if simply to learn and understand more about this piece of history.

The Bradbury Science Museum, New Mexico. Photo and copyright Melissa Hulbert ©, all rights reserved.

The Bradbury Science Museum, New Mexico.
Photo and copyright Melissa Hulbert ©, all rights reserved.

Daily cosmobite: The Andromeda galaxy

Published by Andrew Jacob on No Comments

Andromeda.IsaacRoberts1899Having located Pegasus, the Winged Horse, on Melbourne Cup day now try looking for the Andromeda galaxy – the next closest large spiral galaxy. It is the fuzzy oval below the word ‘Andromeda’ in Tuesday’s cosmobite. From a dark site it appears as pale smudge about the size of your little finger-nail at arms length.

 

 

Even this 1899 image by Isaac Roberts shows more detail then you will see by eye or binoculars.

 

 

 

The official opening reception was held at the New Mexico Museum of Space History. This museum looks at the history of space from the International Space Station back to Dr Robert Goddard’s rocket tests in the 1930s.

Outside the museum is the John P. Stapp Air and Space Park where there are space-related artefacts including the Sonic I wind rocket sled which Goddard rode, the V-2 (Vengeance Weapon-2) the world’s first long-range ballistic missile and the Little Joe 2, a solid-fuelled rocket used to test the Apollo launch escape system.

Photo and copyright Melissa Hulbert ©, all rights reserved.

Little Joe 2, New Mexico Museum of Space History.
Photo and copyright Melissa Hulbert ©, all rights reserved.

The more formal part of the Solar Eclipse Conference covered science from solar eclipses, the benefits of taking videos of eclipses and looking forward to the next three total solar eclipses over the next three years.

Ralph Chou discussed standards for solar viewers/glasses and what happens to those who fail to safely look at the partial phases of an eclipse. Interestingly as there are no pain receptors in the eye, so you would feel no pain while damage is occurring to your eye/s; symptoms usually take about 12-48 hours to appear; that damage is wavelength dependant and visual recovery from this type of damage (called phototoxicity) is variable. The overwhelming message is make sure you safely observe the Sun and eclipses with proper solar filters/glasses – if you’re not sure about it, don’t use it – is your sight really worth the risk?

Fred Espenak is best known for his ‘Mr Eclipse’ web pages, part of NASA’s website. Fred’s new website EclipseWise.com (Fred has retired from NASA) has over 80,000 pages and gif images and one million links relating to eclipses. He has just released his Thousand Year Canon of Solar Eclipses 1501 to 2500 and Thousand Year Canon of Lunar Eclipses 1501 to 2500. Both these publications look at the details for eclipses 500 years into the past and future and are a valuable resource for any eclipse enthusiast.

Focus on the upcoming 2017 eclipse in the USA was a high priority and discussed in detail both in individual talks and panel discussions, focusing on how to let as many people in the US not only be aware of the eclipse, but where to observe and how to observe safely; and the potential logistics for towns and cities in the path as far as being prepared for large numbers of people descending upon them on eclipse day and organising traffic conditions on the day.

Panel discussion for the upcoming 2017 North American Total Solar Eclipse; Fred Espenak, Shadia Habbal, Jay Anderson and Michael Zeiler. Photo and copyright Melissa Hulbert ©, all rights reserved.

Panel discussion for the upcoming 2017 North American Total Solar Eclipse; Fred Espenak, Shadia Habbal, Jay Anderson and Michael Zeiler.
Photo and copyright Melissa Hulbert ©, all rights reserved.

As expected, weather conditions are a major concern for any eclipse and with decisions on location usually made years in advance by observers, the areas likely for the best weather were of major interest. Jay Anderson, a retired meteorologist, discussed the places most likely to give a better chance of clear skies for the next three eclipses over the next three years. However, these are based on studying past weather patterns and of course anything can happen on the day, however being in an area which generally has good conditions on and around the day of the eclipse can increase the likely-hood of clear skies on eclipse day. Needless to say, Jay’s talk was received with great interest.

The Solar Eclipse Conference was a great chance to hear the latest in eclipse observations, science and to prepare for the next three years. Even those with a passing interest in eclipses enjoyed the four days and are eagerly looking forward not only to the next three solar eclipses, but to the next conference in 2018 in Tenerife, Canary Islands.

Daily cosmobite: Moon near Uranus

Published by Andrew Jacob on No Comments

Uranus.Keck.APOD18NOV2004The Moon passes the planet Uranus today as seen from Australian skies. That’s not so unusual, but this time observers in the icy north – Greenland and Iceland – will see the Moon occult, or cover, the ice giant Uranus.

 

The ice giant Uranus as seen by the Keck telescope. Lawrence Sromovsky (Univ. Wisconsin-Madison), Keck Observatory and APOD18NOV2004.

 

 

 

Daily cosmobite: Constellation Pegasus, the Winged Horse

Published by Andrew Jacob on November 4, 2014 No Comments

Pegasus.03NOV2014Pegasus, the Winged Horse, is prominent in the northern sky at present. At first sight it appears simply as a very large square, but closer inspection reveals its head and fore legs.  The square is about a hand-span in size, with your hand held at arm’s length.

 

 

The square of Pegasus dominates the northern sky in the late evening.  Chart generated by TheSky6 © Software Bisque, Inc. www.bisque.com.

 

 

 

 

 

Daily cosmobite: First ever images of a nova explosion

Published by Andrew Jacob on November 3, 2014 No Comments

NovaDel2013.Images.USyd.2014Nova Delphini appeared in our skies in 2013 when material falling onto a white dwarf star from its companion red giant exploded in a thermonuclear fireball. The expanding fireball was beautifully captured in these first ever images made by the CHARA array, an optical interferometer. This very nice piece of work, led by Dr Gail Schaefer, shows the power of optical interferometry to reveal ever finer details of the universe. Read more in the press release.

Images of the expanding thermonuclear fireball of Nova Delphini 2013.  Adapted with permission from image by Georgia State University CHARA Array.

 

 

 

Daily Cosmobite: First quarter Moon – Mare Tranquilitatis

Published by Andrew Jacob on October 31, 2014 No Comments

MoonByHargrave.c1880The Moon is at first quarter phase at 1:48pm (AEDT) today. Mare Tranquilitatis, the landing place of Apollo 11, is clearly visible as an irregular dark patch in the middle of the illuminated hemisphere.

The first quarter Moon photographed by Lawrence Hargrave from Sydney Observatory around 1880.

 

 

 

 

 

ESO/G. Brammer.MWHorizon.potw1412aIn Spring evenings the Milky Way forms a ring around the horizon, as seen from Australia. At midnight on Halloween look up (or is it down?) and you have a clear view to the universe. Out there countless galaxies hurtle away from you in the expanding universe and far away is the cosmic background radiation – the residual glow of the Big Bang.

 

Paranal observatory and the Milky Way on the horizon. ESO/G. Brammer.

 

 

 

 

Daily Cosmobite: Centenary of Sir David Gill’s death

Published by Andrew Jacob on October 29, 2014 2 Comments

David_Gill.wikiSir David Gill died in 1914. Among many achievements he took a photo of the “Great Comet” of 1882. The appearance of previously unseen stars in the background spurred two projects, the Astrographic Catalogue and the Carte du Ciel, to catalogue and map the entire sky using photography.

 

 

 

 

Sir David Gill.  Lick Observatory collection via wiki.

Daily Cosmobite: Moon and Mars in the west

Published by Andrew Jacob on October 28, 2014 No Comments

MoonMars28Oct2014Tonight look for the Moon and Mars in the west. At 8pm the crescent Moon will be two hand-spans (at arm’s length) above the horizon with orange-red Mars a fist-width above and to the left. The Moon’s light takes 1.3 seconds to reach you while light from Mars tonight takes 13.9 minutes.

 

The Moon and Mars in the west on October 28 2014.  Chart generated by TheSky6 © Software Bisque, Inc. www.bisque.com.

 

 

 

 

 

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