ASTR310 - Frontiers of Astronomy and Astrophysics (handbook entry)
We are in the midst of a golden age of astronomy and astrophysics, with results streaming in from a host of telescopes, spacecraft and supercomputers. In this unit students have an opportunity to join this voyage of discovery by planning and conducting their own research project under the guidance of professional astronomers at CSIRO Astronomy and Space Science, the Australian Astronomical Observatory or Macquarie University. Students will develop familiarity with the required tools to tackle a real-world astrophysics problem and conduct their research project. Students report on their progress and findings through presentations and written reports. In alternate years, students have the opportunity to take part in a field trip to major telescopes in Western New South Wales.
ASTR310 Field Trip 2016
Things You Need To Bring - Important!
- Sunscreen + hat
- Warm clothing
- Closed shoes
- Long trousers/jeans
- Small flashlight
- Paper and pencil for taking notes
Field Trip 2016 – Itinerary
|09:00 – 11:00||Leave MQ, drive to Lithgow via Bells Line of Road (via Lawson to collect Mikaela)|
|11:00 – 11:30||Morning coffee stop, Lithgow McDonalds (self)|
|11:30 – 13:30||Drive from Lithgow to Orange|
|13:30 – 14:30||Lunch stop at Orange (self)|
|14:30 – 16:30||Drive from Orange to Overnighter Caravan Park, Parkes|
|16:30 – 17:30||Check in, unpack, refresh|
|17:30 – 19:00||Dinner in Parkes (self)|
|19:00 – 19:30||Return to accommodation|
|19:30 – 22:00||Evening activity: Movie Night: “The Dish”|
|07:00 – 08:30||Breakfast (provided), pack up.|
|08:30 – 11:00||Tour of Parkes radio telescope (Address: Newell Hwy, Parkes NSW 2870 Phone:(02) 6861 1777)|
|11:00 – 11:30||Lunch at visitor centre (Provided)|
|11:30 – 13:00||Drive from Parkes to Dubbo Western Plains Zoo|
|13:00 – 14:00||Lunch (Provided)|
|14:00 – 16:00||Drive to Coonabarabran (Address: 882 Timor road, Coonabarabran NSW 2357|
Phone: (02) 6842 1832)
|16:00 – 17:00||Visit the Diprotodon, Get supplies for BBQ (provided)|
|17:00 – 18:00||Drive to AAT for twilight|
|18:00 – 20:00||Hang out with observers|
|20:00 – 22:00||Return to accommodation for BBQ and evening activities|
|07:00 – 08:30||Breakfast (provided)|
|08:30 – 09:00||Drive to SSO (Address: Observatory Rd, Coonabarabran NSW 2357)|
|09:00 – 12:00||Tour of ANU facilities|
|12:00 – 13:00||Lunch at visitor centre (self)|
|13:00 – 15:00||Daytime tour of AAT|
|15:00 – 17:00||Free time / bush walk|
|17:00 – 18:00||Dinner in Coonabarabran|
|18:00 – 20:00||“Science in the Pub” event (tickets provided)|
|07:00 – 09:00||Breakfast (provided), pack up and leave|
|09:00 – 11:00||Drive from Coonabarabran to Mudgee|
|11:00 – 11:30||Morning coffee, McDonalds (self)|
|11:30 – 13:00||Drive from Mudgee to Lithgow|
|13:00 – 14:00||Lunch in Lithgow (self)|
|14:00 – 16:00||Drive from Lithgow to MQ|
|16:00||Field trip ends|
Siding Springs Observatory
Commissioned in 1974 (read a brief history), the Anglo-Australian Telescope was one of the last 4-metre equatorially mounted telescopes to be constructed. Its excellent optics, exceptional mechanical stability and precision computer control make it one of the finest telescopes in the world. Also important to the AAT’s success has been its suite of state-of-the-art instrumentation, which is constantly being upgraded and improved. Until the 1970s, most of the world largest telescopes had been built in the northern hemisphere. To help redress the balance, the AAT was constructed in Australia so that astronomers could explore in detail some of the most exciting regions of the sky, including the centre of our own Milky Way Galaxy and its nearest neighbours the Magellanic Clouds. Some of the finest globular clusters and nearest radio galaxies can only be seen with difficulty from northern latitudes, if at all.
The AAT can be used in many configurations, each requiring a different instrument or detector to collect and analyse the light. Most astronomers use charge coupled devices (CCDs) to collect data. These highly sensitive solid state devices convert feeble light into digital signals which are then collected and stored on computers for further analysis, rather like an electronic photograph. However, traditional photography is also still used for special projects.
The most commonly used instruments on the AAT are its spectrographs, which split the light from distant objects into its constituent colours. Parts of the resulting spectrum can then be studied in detail to measure important properties such as the temperature, chemical composition, velocity or distance of an object, revealing vital facts about distant stars, galaxies and nebulae that photographs cannot show.
Other specialised instruments collect ‘light’ energy from the infrared (IR) region of the spectrum and are thus sensitive to the temperature of objects too cool to emit visible light. Using the most recent technical advances, the AAO has taken a lead in designing and building IR instruments, the latest of which, IRIS, provides both images and spectra of the sky. New IR instruments are currently under consideration. Infrared images are especially useful for studying the earliest stages of star formation, normally hidden at visible wavelengths by dust clouds.
Over the past decade the AAO has pioneered the use of optical fibres in astronomy and currently leads the world in this work. The latest of these instruments, the Two-Degree Field facility (or 2dF) uses flexible optical fibres, to collect the light from up to 400 faint stars or galaxies from a two degree field of view. This light is directed to a spectrograph, where the 400 individual spectra are detected by a CCD for analysis. Two degrees of sky is about four Moon diameters across, and is a four-fold increase in area of the AAT prime focus, which was already considered to be wide field for a 4-m telescope. This instrument dramatically improves the efficiency of the telescope, which has traditionally observed one object at a time, allowing astronomers to carry out previously impractical observing projects.
THE AAT: FACTS & FIGURES
|Base of Dome||1134m||Length||15m|
|Top of Dome||1184m||Wgt of central tube/mirrors||116 tonnes|
|Wgt with horseshoe mounting||260 tonnes|
|Working diameter||3.893m||OTHER MIRRORS|
|Thickness at outer edge||0.63m||Total number||8|
|Weight||16.19 tonnes||Maximum in use at any time||4|
|Cervit blank cast||May 1969||Diameters||0.376-1.47m|
|Figuring of surface completed||June 1973||Weight of largest||860kg|
|Diameter of central hole||1.067m|
|Coated annually||2.5g of aluminium||BUILDING|
|Height (to base of dome)||26m|
|Diameter||37m||Depth of excavation||0.3m|
|Weight||560 tonnes||No. of floors or part floors||9|
|Roatation time||5 min|
|Rotates at 32 bogeys||DIRECTORS|
|Driven by||4 3.5kW DC motors||Dr E J Wampler||Sep 1974 – Mar 1976|
|Dr D C Morton||Jul 1976 – Mar 1986|
|OBSERVING||Dr R D Cannon||Oct 1986 – Sep 1996|
|Av. clear night time||65%||Dr B J Boyle||Oct 1996 – Jul 2003|
|Typical scheduling: Observing||341 nights||Prof M M Colless||Jan 2004 –|
|Instrument tests etc||20 nights|
|Aluminising primary mirror||4 nights|
|Astronomers using the AAT||250 per year|
For further information, including manuals, observing guides and technical specifications, try the Instruments & Documentation page.
GALAH: GALactic Archaeology with HERMES
HERMES: A High Efficiency and Resolution Multi-Element Spectrograph
HERMES is a new high resolution fibre-fed multi-object spectrometer. It has four non-contiguous spectral bands, covering a total of approximately 100 nm between about 470 nm and 790 nm. These bands were selected to permit the measurement of the abundances of as many elements as possible from the major nucleosynthetic processes.
|Band||λmin (nm)||λmax (nm)|
HERMES also has two resolution modes, 28,000 and 50,000. The high resolution mode is achieved using a mask and results in 50% light loss. The instrument has a single collimator and four VPH gratings and cameras, with the bands separated by dichroic beam splitters. Each camera has a 4x4K E2V CCD detector.
HERMES utilizes the existing 2-degree field (2dF) positioner. This allows for up to 392 simultanaeous spectra of objects anywhere within a two degree diameter on the sky. Each fiber has a diameter of 2.1 arcsec. 2dF also has a wide-field corrector, an atmospheric dispersion compensator, and a robot gantry, which positions optical fibers to 0.3 arcseconds on the sky. It is also able to configure a field while observing another one.
|The optical design of the HERMES four-band high-resolution spectrograph. (Credit: Australian Astronomical Observatory)|
HERMES is a four channel fibre-fed spectrograph with high resolution and multi-object capability. It provides a nominal spectral resolution of R~28,000, and an option of higher resolution of R~50,000 using a slit-mask at the cost of approximately 50% light loss. HERMES provides simultaneous observations in the following fixed optical bands:
Blue: 471.5 – 490.0 nm
Green: 564.9 – 587.3 nm
Red: 647.8 – 673.7 nm
IR: 758.5 – 788.7 nm
The HERMES system is built upon the AAT’s existing Two-Degree Field (2dF) optical fibre positioner. The Two Degree Field system (“2dF”) is the AAT’s most complex astronomical instrument. It is designed to allow the acquisition of up to 392 simultaneous spectra of objects anywhere within a two degree field on the sky. It consists of a wide-field corrector, an atmospheric dispersion compensator and a robot gantry which positions optical fibres to 0.3 arcseconds on the sky. A tumbling mechanism with two field plates allows the next field to be configured while the current field is being observed.
The ANU 2.3m Telescope was built in the early 1980s, at the initiative of the then director, Don Mathewson. The entire project was managed by the observatory’s own technical staff, and a large amount of the construction was also undertaken in-house. The design of the 2.3m Telescope, also called the Advanced Technology Telescope, incorporated three radical features never before combined in a single instrument – an uncommonly thin mirror, an alt-az mount, and a rotating building.
The 2.3m Telescope is frequently used by students from RSAA and other universities, and provides hands-on experience of observing with a large optical astronomical telescope.
Observing time on the 2.3m Telescope is allocated by the RSAA time assignment committee each quarter based on written applications for use. See the Information for observers page for more information about who can apply, and how to apply for time.
- 2.3m, f/2.05 primary mirror
- 4715mm focal length
- 2300mm outside diameter
- 500mm diameter central hole
- 3.973 square metre collecting area
- 0.3m, f/7.85 secondary for Nasmyth
- 18056mm focal length
- Plate scale : 4.964 arcsec/mm
- 80mm diameter (6.62 arcmin) unvignetted field of view
- 0.3m, f/7.85 tip-tilt secondary for Cassegrain (18056mm focal length )
- Alt-Azimuth telecope mount
The UK Schmidt Telescope (UKST) is a survey telescope with an aperture of 1.2 metres and a very wide-angle field of view. The telescope was commissioned in 1973 and, until 1988, was operated by the Royal Observatory, Edinburgh. It became part of the AAO in June 1988.
The telescope was designed to photograph 6.6 x 6.6 degree areas of the night sky on plates 356 x 356 mm (14 x 14 inches) sqare in order to produce photgraphic aylases of the night sky. The UKST’s initial task was the first deep, blue-light photographic survey of the southern skies, which was completed in the 1980s. It then undertook many other survey projects in different colours and in the near infrared, notably the Second Epoch Sky Survey in collaboration with Space Telescope Science Institute. The telescope’s final photographic survey was the H-alpha Survey of the Milky Way and Magellanic Clouds using a special filter to isolate the light of glowing hydrogen. Its photographic work was completed in 2005 when the last H-alpha exposure was taken.
The excellent optics and wide field of the telescope were subsequently exploited by the 6dF(6-degree Field) system, a multi-object fibre-optic spectrograph facility, which can obtain the spectra of more than 100 objects in a single field simultaneously. 6dF was commissioned in 2001, having been based on earlier prototypes such as the pioneering FLAIR system of the early 1980s.
The 6dF system was used from 2001 to 2005 to carry out the 6dF Galaxy Survey(link is external), which measured the redshifts of more than 120,000 galaxies over the whole southern sky, with more detailed measurements being made for the brightest 10,000 of them.
From 2003-2013 the UKST was operated by the AAO under funding from the internationalRAVE(link is external) (RAdial Velocity Experiment) project. Using 6dF, RAVE measured radial velocities (with an accuracy of ~1km/s) and physical parameters for about half a million stars in our Galaxy.
The UKST is undergoing refurbishment during 2014-15 in order to allow remote operations, and to install a new spectrograph and fibre positioning system using the AAO’s novel “starbug(link is external)” technology. The upgraded system will be used from 2016 for two new survey projects, called Taipan(link is external) and Funnelweb(link is external).
The characteristics of UKST and the AAT complement each other perfectly and many AAT projects depend on the wide field capabilities of the UKST. For example, the telescopes of the Anglo-Australian Observatory have together discovered and confirmed a large number of distant quasars, the most energetic but often the most distant objects in the Universe.
Parkes Observatory, just outside the central-west NSW town of Parkes, hosts the 64-metre Parkes radio telescope, one of the telescopes comprising CSIRO’s Australia Telescope National Facility.
An icon of Australian science, the Parkes radio telescope has been in operation since 1961 and continues to be at the forefront of astronomical discovery thanks to regular upgrades.
Astronomers from across Australia and around the world utilise the Parkes radio telescope to undertake world-class astronomical science. Affectionately known as ’the Dish’, the telescope operates 24 hours a day, every day of the year.
During the nights we will be taking some images with the equipment we are taking away with us. To make the process easier, we need to select the targets before we head off.
Preparing for a Telescope Observing Run
Observing with a telescope is the primary way astronomers learn about the universe. This practical is designed to prepare you for an observing run using the Macquarie Observatory. It is normally very difficult to get time on large telescopes, so professional astronomers will prepare their astronomical targets they want to observe many months in advance of the actual telescope observing run. They also have to build a convincing scientific case that a committee of other astronomers will review and determine if they should get time to observe their programme.
There are a number of technical factors that you must consider when selecting a target at the telescope:
|Apparent magnitude of target||How long you must observe it|
|Wavelength of observations||Telescope, camera/instrument, filter|
|Angular size of target||Telescope, camera/instrument|
|Location of target||When and where you can observe it|
|Objective of observations||Filters, wavelengths, exposure time|
But of course, the most interesting factor is the reason you are observing the target. Is it scientifically interesting? Will the image just look great? Just curious?
Choose 3 targets: star clusters, nebulae, galaxies or whatever you’d like. Wikipedia has some convenient lists:
- See also: http://www.atscope.com.au/astrophoto.html
You can get more information about individual targets here: http://ned.ipac.caltech.edu/forms/byname.html
Click on the ‘phot’ link to get apparent magnitudes for your object.
Coordinate transformations can be performed here:
To make sure your targets are observable this week, use: http://catserver.ing.iac.es/staralt/. You need to select Siding Springs Observatory as the location. Be sure you are using Equatorial (J2000.0) coordinates for your targets. For example:
NGC5128 201.3650633 -43.0191125
Select the output chart mode (staralt) that plots airmass/altitude against time. This is a visibility chart, which shows how high above the horizon your targets are at SSO on the date you selected during the night. Make sure your target has an airmass of 1.5 or smaller when you expect to observe the target.
Print out your object visibility chart for your 3 objects. Note, you can put multiple targets onto one chart.
Next, we’ll make finding charts for your targets. Finding charts are images of the piece of sky that you plan to observe. They help you determine if you are pointing at the right location when you are at the telescope. This is especially important if your target is very faint and will be difficult to see in a single image you take at the telescope.
To make a finding chart, go to this website and enter in the name of your target (you might need to find the target’s NGC number or Messier name for it to work):
Click on the ChangeSize link under the Size column. Specify the correct field of view (height & width of image) for the camera we are using: 21.5 arcmin by 16.2 arcmin. Click and download the Preview image.
Next do the following:
- Print the finding charts for each of your targets.
- Record the information listed in Table 1 for each target.
- Finally, select your favourite target from the 3 you have selected.
Diprotodon, meaning “two forward teeth”, is the largest known marsupial ever to have lived. Along with many other members of a group of unusual species collectively called the “Australian megafauna“, it existed from approximately 1.6 million years ago until extinction some 46,000 years ago (through most of the Pleistocene epoch).
Diprotodon species fossils have been found in sites across mainland Australia, including complete skulls and skeletons, as well as hair and foot impressions. Female skeletons have been found with babies located where the mother’s pouch would have been. The largest specimens were hippopotamus-sized: about 3 metres (9.8 ft) from nose to tail, standing 2 metres (6.6 ft) tall at the shoulder and weighing about 2,790 kilograms (6,150 lb).[n 1] Aboriginal rock art images in Quinkan traditional country (Queensland, Australia) have been claimed to depict diprotodonts. They inhabited open forest, woodlands, and grasslands, possibly staying close to water, and eating leaves, shrubs, and some grasses.
The closest surviving relatives of Diprotodon are the wombats and the koala. It is suggested that diprotodonts may have been an inspiration for the legends of the bunyip, as some Aboriginal tribes identify Diprotodonbones as those of “bunyips”.
The Warrumbungles are a mountain range in the Orana region of New South Wales, Australia. The nearest town is Coonabarabran. The area is easiest accessed from the Newell Highway which is the major road link directly between Melbourne, Victoria and Brisbane,Queensland and cuts across inland New South Wales from the north to the south.
As the range is between the moist eastern coastal zone and the dryer plains to the west, it has provided protection for flora and fauna suited to both habitats. There are over 120 bird species identified on the range, including lories and lorikeets, rosellas and parrots. The centre of the range has served as an area of protection for a healthy and content colony of grey kangaroos. These animals have become fairly tame due to constant visitor attention and are easily approached.
The main features of the Warrumbungle mountains are a series of huge jagged outcrops in a roughly circular pattern, surrounded by hilly bush and woodland forest. Dykes, plugs and domes are common and mostly made from trachyte. The Grand High Tops is a section of the range where volcanic remnants are especially clustered. These vents and rocky formations are all named – Belougery Spire, Belougery Split Rock, Crater Bluff, Bluff Mountain, The Breadknife and Mount Exmouth. Pyroclastic rock is found in this area. The Breadknife, a straight wall of jagged rock nearly 100 metres (330 ft) high, is particularly rare. There is an extensive network of nine walkingtracks across the central peaks.
Towards the southeast a broad belt of basalt outcrops extends towards the Liverpool Range. Near Chalk Mountain are outcrops ofdiatomite. Outer stretches of the volcano are made up of hawaiite and mugearite.