First Ever Photograph of a Black Hole

In another great step forward for astronomical science, we now have the first ever image of a black hole. This tremendous feat has been difficult to achieve because one of the crucial characteristics of a black hole is that gravity is so strong that not even light can escape. And if light cannot escape, there is no way for us humans to “see” it.

Also, black holes are millions of light years away, so any possibility of observing anything which could give away the existence of a black hole would be very faint and difficult to spot.

The problem was solved by using the Event Horizon Telescope (EHT), a network of radio telescopes based all around the Earth. Eight different telescope arrays were used: from Hawaii in the west to the IRAM 30 metre telescope in Europe to the east; and from Alaska in the north to the Atacama Desert in Chile and the polar observatory in Antarctica, which is as far south as it’s possible to get. This technique effectively uses the whole planet as one big telescope to create a gigantic lens.

Observers have long suspected from the behaviour of its stars that the galaxy M87, 55 light years away from Earth, had a black hole at its centre. So all the telescopes were organised to point at this distant spot in the sky to try to photograph the phenomenon. The experiment also required every location to take their observations at precisely the same time, and for weather conditions in every place to be ideal, with clear overhead visibility.

The amount of information required was also immense. Around five petabytes was collected in total. This is equivalent to around 5,000 years’ worth of MP3 files.

This was far too much data to send over the internet. Instead, it had to be stored on hundreds of unique hard drives (there was too much data to back them up). These had to be couriered to the experiment HQ in Boston in the United States. The scientists even had to wait six months for the data from the South Pole, which could not be transported until the polar winter was over. It took nearly two years to compile, analyse and assemble all the information.

What these scientists were hoping to capture was radio waves sent from the very edge of the black hole. As gas and dust which surrounds the hole begins to be sucked in, it revolves around the hole very quickly, a bit like bath water approaching a plughole. This causes the gas to become superheated, which sends out the radio waves.

This is precisely what was observed when the EHT scientists triumphantly announced their photograph to the world on Wednesday 10th April. The image shows a bright yellow / orange ring, a bit like a doughnut, where the black hole is represented by the dark “hole in the middle”.

Based on its observations, the EHT team estimate the M87 black hole’s mass to be roughly equivalent to around 6.5 billion suns. Its estimated size means that if it were placed where our sun is, the event horizon would be situated far beyond the orbit of Pluto.

SpaceX Falcon Heavy successful launch

Elon Musk’s SpaceX company successfully launched its Falcon Heavy rocket on April 11th. This is currently the most powerful launch system available anywhere in the world – the most powerful rocket since NASA’s Saturn V, used to launch the Apollo missions. This flight was also the Falcon Heavy’s first commercial launch: a Saudi Arabian telecommunication satellite, Arabsat 6A was the payload.

The mission was also notable for the stunning footage of all three booster rockets being successfully returned to Earth for future re-use. The side boosters were safely landed at their designated landing pads, while the main centre rocket was returned to a drone ship stationed on the Atlantic Ocean.

More milestones for UK space technology

Oxfordshire based company Reaction Engines has been developing a new prototype air-breathing rocket called Sabre, which is designed to be capable of putting space planes into orbit. More importantly from an aviation point of view, the new rocket would also be capable of carrying passengers across the world in just a few hours. Theoretically, this would even make day trips to Australia a feasible (if expensive) possibility.

The prototype engine is a kind of jet / rocket hybrid. It uses a jet engine to fly at conventional speeds, then switches to rocket power to accelerate beyond the sound barrier (Mach 1).

The biggest problem for such a propulsion system is the heat that is produced: generating temperatures which would be sufficient to melt the insides of a normal engine. The good news is that the latest tests have proved successful. A rocket was fired on the ground at the company’s testing facilities in Colorado in the United States. The test simulated speeds of around Mach 3.

The new engine contains some nifty pre-cooling technology: chilled helium is used to keep temperatures down. The company is confident that this technique will work at speeds of up to Mach 5. The engine has also passed a design review by the European Space Agency (ESA)

Reaction Engines is developing its Sabre engine in conjunction with some big name aerospace companies, like Boeing, BAE Systems and Rolls Royce. These companies are providing the financial muscle and technical back up which could well make this technology a practical possibility in the near future.

Meanwhile, another Oxfordshire based outfit called Oxford Space Systems and its partners Surrey Satellite Technology are developing a new satellite radar system. This is scheduled for a test launch in 2021.

This new technology has two major advantages. It has the ability to image the ground surface in any conditions: day or night, cloudy or clear. It is also very low cost. Using the latest miniaturisation techniques, it may be able to reduce satellite weight to just a couple of hundred kilograms or even less, greatly reducing manufacture and launch costs.

Israeli Moon landing crash

The privately funded mission was attempting to enable Israel to become just the fourth nation to successfully soft land a spacecraft on the Moon after the United States, Russia and China. Unfortunately, the Beresheet lander crash landed on the lunar surface on April 11th.

The UK manufactured engine was at first thought to be to blame for the failure, but it now appears that a software or technical glitch was the cause. Initial investigations suggest a sensor misread the altitude of the craft and shut the engine down early. By the time the systems were re-set and the engine re-fired, it was too late. The craft was estimated to have hit the lunar surface at around 300 mph – not really the soft landing the spacecraft was designed for.

First “Marsquake” detected

NASA’s InSight lander has detected a seismic event on Mars. The tremor, which was picked up by the craft’s seismometer on April 6th, is the first quake to be detected on a planetary body other than on Earth or the Moon. The vibrations were slight – it would not register very highly on an Earth type Richter scale. But Mars is not very geologically active and is generally very quiet, so the tremor produced a clear unmistakeable signal.

It is difficult to be sure of the cause of the quake from the data collected, but possibilities include movement of a fault within the planet, a meteorite strike or possible shifting of the surface due to temperature changes as the planet revolves.