BCO Labs: Projects

Robotic Astronomy Article on Robotic Astronomy

Virtual Astronomy Article on Virtual Astronomy

IAU: Minor Planet Centre IAU: Minor Planet Center

Researchers at Blackrock Castle Observatory are currently working on a number of projects. These projects require many different types of expertise and underlines the fact that science draws from many fields of knowledge to solve problems. The projects described below while driven by scientific inquiry also contribute to engineering and technology.

Robotic Telescopes - Telescopes That Think

One of the most fascinating facts about the Blackrock Castle Observatory is that the telescopes and domes must operate without any human assistance. This means the observatory has to do some "thinking" for itself. The "thinking" is done by computers that have been programmed to take specific actions under certain conditions. For example, when the weather station notifies the computers that the skies are clear and it's safe to open the domes, the computers swing into action, opening the domes and deciding which targets the telescopes should look at that night. They also have to decide on many other things, including whether the telescope is pointing at the right part of the sky and whether every piece of equipment that's needed to make successful observations is functioning ok.

It is not a simple task to get computers to "think", and researchers at the observatory have to write many new computer programmes themselves to do this. They also have to develop new electronic circuits which can sense if some piece of equipment is malfunctioning - a good example would be sensing if a dome is stuck open. An open dome can be catastrophic if it starts to rain, so it's really important to be sure that the dome can be closed when it needs to be.

The two optical telescopes at Blackrock Castle Observatory are also linked in a robotic way. Normally, the two telescopes operate separately, looking at different objects in the sky, but if one of them finds something interesting it can automatically send a signal to the second telescope to tell it to stop what it's doing and switch its attention to the interesting object. This information can even be transmitted to telescopes abroad.

Instrument Design - SFI Two Colour Photometer

Astronomers often make new discoveries by building better instruments with which to view the universe. Indeed it could be argued that many of the biggest discoveries were made because of new inventions. For example, when Galilieo invented the telescope, he was able to use it to disprove the belief, held for some 2000 years that the earth is at the center of the universe.

At Blackrock Castle Observatory we're always looking for new ideas which we can use to build better instruments. We're currently building a new type of light detector, called a photometer, which uses the best digital camera sensors available anywhere in the world. The money to build the photometer comes from Science Foundation Ireland (SFI). When the photometer is completed in 2006, it will be used to study active galaxies with unprecedented accuracy. The photometer will be used mainly on telescopes in Greece, Spain and South Africa. It will also be used by astronomers from other observatories for their own projects.

White light from objects in space enters the photometer through focusing optics which sends the light to a dichroic beam splitter, which splits the white light into two beams. Red and blue filters are used to extract the red and blue light from each beam of white light. The red and blue light is then imaged onto a CCD camera. (Image: Blackrock Castle Observatory)

Automatic Image Analysis - Computers Searching For Asteroids

Every clear night we can expect hundreds of images of the night sky to be taken by the telescopes at the observatory. This is too many to analyse individually, so we have had to develop more computer programmes which can do the job automatically. This process is called a "data pipeline" because it's a little bit like a pipe where you put in the images at one end and the results come out the other end.

Much of the time, the telescopes are searching the skies for signs of extrasolar planets, or near-earth objects, or taking pictures of distant objects in space. The techniques required to analyse these different types of images vary. As an example, consider what we do when searching for near-earth objects. One of the telescopes takes two or more pictures of a selected part of the sky, perhaps on different nights. Our computer programmes analyse the images to look for evidence of something that has moved.

The more an object moves between the two images, the more chance there is that it's close to earth, and the more important it is to track its orbit to see if there's any possibility of a collision.

Four separate images (a)(b)(c)(d) of a starfield taken at different times are shown above. An asteroid (Asteroid 1997 XF11) is also present in the field. (Images: SpaceWatch Project)

The images above show a starfield taken at four different times in which an asteroid is present. The asteroid moves relative to the background stars which appear fixed. You can see for a human to look at even these four images and find an object moving is quite difficult, it would be an impossible task for a human if there were thousands of these images. For a computer however, running specialised software (which we develop at Blackrock Castle Observatory), the task can be done quickly and accurately. With software, it is possible to instruct the computer to look at the images in a different way to us, a way which shows the asteroid clearly. The software used to search these images only notices differences between the images. Remember, the background stars will always appear in the same locations in the image, because they don't move (thats what the tracking function of a telescope does). So instead of seeing these four images, our software only looks at one image, showing the differences. The computer sees the image below (a red crosshair is placed where there is the most difference, the image is larger for clarity).

Our software reduces these four images to one single image which only shows the differences between the images. Since the asteroid moves relative to the fixed background stars, its path becomes apparent in the difference image.

Using this image, the computer can now see the asteroid moving and show us where it is. The computer can then redisplay a new image which shows where the asteroid is in the starfield.

Once the asteroid location has been determined, its path can be superimposed on any one of the original images to show us its location in the image.

It can also show us the direction in which the asteroid is moving.

As well as the location, the software can also determine the direction the asteroid is moving.

Radio Telescopes

A radio telescope detects a type of light that cannot be seen by the human eye, or indeed the eye of any animal. We are all familiar with radio waves, even if we don't know it - both televisions and mobile phones use radio waves to operate, for example.

Many objects in the universe emit radio waves. Indeed radio emissions can often tell us more about an object than the visible light they give off and radio images can look dramatically different to optical ones. Also, radio waves can penetrate clouds and radio telescopes can be used both night and day. At Blackrock Castle Observatory, we will install a radio telescope to detect radio emissions from different objects in space, including the Sun and the planet Jupiter. These emissions will be displayed on this website. Its main function will be as a useful tool for teaching more about radio astronomy.

Optical image of Centaurus A. (Image: NOAO)

Radio image of Centaurus A. (Image: Jack O. Burns (University of Missouri) & David Clarke (St. Mary's University, Nova Scotia))

Further Reading

How the Arecibo radio telescope works

The StarDial Project