Astronomy: New telescope enables observations even in the middle of the day
The giant star Betelgeuse cannot be observed at night for months every year. A new telescope is to provide a remedy and fulfill an old dream.
Das Huntsman Telescope
(Image: Macquarie University)
A group led by astronomer Sarah Caddy has used a special telescope to prove that astronomy can be successfully carried out in daylight for certain celestial objects. The Australian Macquarie University, which operates the Huntsman Telescope at the Siding Spring Observatory, has made this public. The device is made up of ten standard Canon digital cameras and achieves an absolute photometric accuracy of one to ten percent for astronomical observations during the day. Even if this is not sufficient for state-of-the-art research, it can be used to keep an eye on bright stars such as Betelgeuse from the ground when they disappear from the night sky, sometimes for months at a time.
(Image: Macquarie University)
Enabling long-term observations
With the telescope and the astronomical conditions during the day, a centuries-old dream has been realized, writes the team. Astronomy in the visible wave range is very difficult because of the sun and the bright Earth's atmosphere. The problem was solved not only with the special design of the telescope and the light-sensitive cameras, but also with special broadband filters. According to the university, these filter out most of the sunlight but allow specific wavelengths of astronomical objects to pass through. A comparison of data collected in this way with that of other observatories and space telescopes has shown that they match.
A telescope for astronomical images during the day could add important aspects to the research, the team explains. For example, Betelgeuse, one of the brightest and most interesting stars for research, is regularly so close to the sun for months at a time that it cannot be observed from the Earth's surface at night. At the same time, however, it is - in astronomical terms - on the verge of the final supernova. It is therefore at least conceivable that the star will explode and we will not notice it for months. Space telescopes that could see this usually only focus on small sections of the sky and therefore do not provide an overview of the night sky. This is where devices such as the Huntsman Telescope could help.
The research work now published on the validation of the telescope in daylight paves the way for uninterrupted long-term observations of stars such as Betelgeuse, which are approaching the end of their lives, writes the university. In addition, such observations would also offer a huge advantage when it comes to keeping track of satellites, space debris and other man-made objects in Earth orbit. With tens of thousands of satellites soon to be orbiting the Earth, telescopes are needed to keep an eye out for possible collisions around the clock. As a test for this next era of space travel, the team also kept an eye on the International Space Station (ISS) during the day.
(mho)