London's most powerful telescope will hunt oxygen far beyond our solar system

A new £40,000 spectrometer attachment will measure the mass and energy of particles
This “firework galaxy" with its exploding supernovae, catalogued as NGC6946, was captured by London students from 22.5 million light years away
UCL Observatory
Mark Blunden @_MarkBlunden18 September 2020

Scientists are customising London's most powerful telescope to hunt for traces of life-supporting gases far, far away across the universe.

A £320,000 remote-controlled robot telescope at UCL's Mill Hill observatory will soon be fitted with a new spectrometer able to measure oxygen and nitrogen in other galaxies.

But astronomers fear their view of the night sky risks being polluted by thousands of satellites launched by ventures such as Elon Musk’s Starlink, which plans a “constellation” of orbiting transmitters beaming down broadband.

The new £40,000 spectrometer attachment measures the mass and energy of particles but requires calibration on to its host telescope.

It is due for delivery this month before being ready for use by students early next year at the teaching facility sandwiched between the M1 and Watford Way.

The Perren telescope is the most powerful in London - and will become even more sensitive with the fitting of a custom spectrometer (UCL Observatory)
UCL

Its blue host telescope, called Perren, is controlled by computer and already captures moving objects such as near-Earth asteroids to help understand the evolution of exoplanets - planets outside of our solar system.

The observatory’s two other telescopes - including a bronze and brass model dating from 1862 that would be at home in a Jules Verne novel - have also produced images of spiral and bar galaxies 30 million light-years away, double the size of our own Milky Way.

Professor Giorgio Savini, the observatory’s director, said: “Finding the capability to support life is not something you can do with a simple telescope, you need to detect the presence of oxygen and nitrogen.

“We need spectroscopy to start doing those kinds of measurements.”

This M1 "crab supernovae" shows remnants of an explosion in 1054 - 12 years before the Battle of Hastings (UCL Observatory)
UCL

London students are also able to remotely capture even higher resolution galactic images via super-powerful optical instruments on a mountainside in Chile as part of the Telescope Live project.

But Professor Savini is among astronomers concerned about increasing levels of light pollution from commercial satellites in low-Earth orbits, which produce “streaks” in images due to reflections off the device’s body and solar panels during long-exposure photographs using colour filters.

Photographing distant galaxies can take hours of exposure, meaning the slightest movement ruins the shot.

Musk’s Starlink project is launching scores of satellites in batches using SpaceX rockets with aim of providing blanket broadband access, with plans to launch around 12,000 of them in a “constellation”.

Professor Giorgio Savini with the Fry telescope, which was built in 1862 using brass and bronze components
Matt Writtle

Amazon founder Jeff Bezos also plans to launch more than 3,200 satellites for a similar internet project.

Professor Savini said: “Astronomers and astrophotographers are all generally worried.

“The concern is that the pictures we take for studying and teaching purposes will be contaminated with streaks of satellites.

The M8 "lagoon nebula" is about 5,000 light years away and was captured by London students using a remote-controlled telescope in Chile (UCL Observatory)
UCL

“It’s great to have the capability of having thousands of satellites and internet available to everyone.

"But there is a worry because the night sky is an asset, something which should be protected.

“We’re so much in a hurry we don’t know if there’s animal species that use the starry sky for certain purposes, is it going to confuse insects or birds?

Centaurus A, an edge-on galaxy, has a super-massive black hole at its centre equivalent to 50 million suns. This image was captured by UCL students using a remote telescope in Chile (UCL Observatory)
UCL

“SpaceX has been discussing with astronomers how to mitigate the effect.

“Painting certain parts of a satellite black, they say, will reduce the reflection but in astronomy we observe things that are one part in 10 million, so even if you reduce it by 90 per cent that's not going to make a huge difference.”

Professor Savini added that Londoners are able to glimpse planets with the naked eye and a clear-ish sky, including Venus at dawn or twilight and potentially Mercury if it is in the right position.