Humankind's most distant outpost was recently captured crossing the face of our enormous and gleaming Sun. The fleeting transit of the International Space Station was over in the blink of an eye, but Ian Griffin, Director at the Otago Museum of New Zealand, made sure he was in the right place to capture it.
“A transit was predicted about 130 km from my home in Dunedin on New Zealand's South Island. So, I packed my telescope into my car and drove for approximately 2 hours”, explains Ian.
“On Thursday 31 January, at 11:07 NZDT, the International Space Station crossed the Sun in less time than a human heart beats once, and I was there to witness it”.
The Space Station, slightly larger in size than a football field, orbits Earth every 92 minutes. It is one of the most remarkable endeavours our species has ever embarked upon, yet it pales in comparison to the size and power of our star.
This remarkable spectacle serves as a much needed reminder that the people and technology we send into space can be affected by solar activity, and the changing environment .
One of the largest geomagnetic storms on record, the Carrington event of 1859, was caused as a fast coronal mass ejection associated with an enormous solar flare struck Earth’s magnetosphere. The impact created auroras as far north as Queensland, Australia, and as far south as the Caribbean.
Telegraph systems across Europe and North America failed, with reports of some operators receiving electric shocks and telegraph pylons sending out sparks.
Today, a storm of this magnitude would create far greater disruption, as we become ever-more dependent on infrastructure in space and on Earth that is vulnerable to the outbursts of the Sun.
As part of ESA’s Space Safety & Security activities, the Space Weather Office is working to minimise the potential damage and disruption these events can cause. The future Lagrange mission will keep a constant eye on the Sun, sending timely warnings via the Space Weather Service Network to operators and controllers of vital infrastructure, giving them time to take protective measures.
This early warning system will also be of great importance to astronauts and future explorers to the Moon and Mars, who, vulnerable to the radiation emitted during these extreme events will need time to get to safety.
Find out more:
From 3-5 March, ESA and the Norwegian Space Agency are coming together for the #AuroraHunters SocialSpace, live from Tromso, Norway. Together with a group of 30 attendees, selected from hundreds of applicants across the globe, we will be highlighting the affects of the Sun on our infrastructure, technologies and skies – in the form of the awesome Aurora. Keep an eye on @esaoperations and follow the hastag #AuroraHunters on twitter to keep up with the event.
The Copernicus Sentinel-3A satellite takes us over the high, snow-studded Alps under clear skies.
The Alps extend 1200 km through eight different countries: France, Monaco, Italy, Switzerland, Liechtenstein, Germany, Austria and Slovenia. This mountain range, which is inhabited by some 20 million people, covers an area of approximately 200 000 sq km.
Captured on 16 February 2019, this true-colour image shows little clouds, particularly over the Alps and the surrounding flatter lands in southern France. There is an interesting contrast between this and the haze hanging over the Po valley in Italy, directly south of the Alps. The haze is most likely to be a mix of both fog and smog, trapped at the base of the Alps owing to both its topography and atmospheric conditions.
Patches of snow are also visible on the island of Corsica, to the left of mainland Italy, Croatia, to the right, and at the bottom of the Apennines in central Italy. Most of Italy’s rivers find their source in the Apennines, including the Tiber and the Arno.
The Adriatic Sea to the east of Italy is visible in turquoise, particularly the coastal area surrounding the Gargano National Park, jutting out. This light-green colour of the sea along the coast is likely to be caused by sediment carried into the sea by river discharge.
Directly to the right of the Alps, the image shows a pale-green Lake Neusiedl straddling the Austrian-Hungarian border. Neusiedl, meaning ‘swamp’ in Hungarian, is the largest endorheic lake in central Europe, meaning water flows into but not out of the lake, hence its size and level frequently fluctuates. It is a popular area for windsurfing, sailing and spotting the woolly Mangalica pig.
To the right, the freshwater Lake Balaton is visible, and is the largest lake in central Europe. It stretches for over 75 km in the southern foothills of Hungary. Its striking emerald-green colour is probably down to the presence of algae that grow in the shallow waters.
Sentinel-3 is a two-satellite mission to supply the coverage and data delivery needed for Europe’s Copernicus environmental monitoring programme. The mission provides critical information for a range of applications from marine observations to large-area vegetation monitoring. The satellite’s instrument package includes an optical sensor to monitor changes in the colour of Earth’s surfaces.
This image is also featured on the Earth from Space video programme.
This swirling palette of colours portrays the life cycle of stars in a spiral galaxy known as NGC 300.
Located some six million light-years away, NGC 300 is relatively nearby. It is one of the closest galaxies beyond the Local Group – the hub of galaxies to which our own Milky Way galaxy belongs. Due to its proximity, it is a favourite target for astronomers to study stellar processes in spiral galaxies.
The population of stars in their prime is shown in this image in green hues, based on optical observations performed with the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at La Silla, Chile. Red colours indicate the glow of cosmic dust in the interstellar medium that pervades the galaxy: this information derives from infrared observations made with NASA’s Spitzer space telescope, and can be used to trace stellar nurseries and future stellar generations across NGC 300.
A complementary perspective on this galaxy’s composition comes from data collected in X-rays by ESA’s XMM-Newton space observatory, shown in blue. These represent the end points of the stellar life cycle, including massive stars on the verge of blasting out as supernovas, remnants of supernova explosions, neutron stars, and black holes. Many of these X-ray sources are located in NGC 300, while others – especially towards the edges of the image – are foreground objects in our own Galaxy, or background galaxies even farther away.
The sizeable blue blob immediately to the left of the galaxy’s centre is especially interesting, featuring two intriguing sources that are part of NGC 300 and shine brightly in X-rays.
One of them, known as NGC 300 X-1, is in fact a binary system, consisting of a Wolf-Rayet star – an ageing hot, massive and luminous type star that drives strong winds into its surroundings – and a black hole, the compact remains of what was once another massive, hot star. As matter from the star flows towards the black hole, it is heated up to temperatures of millions of degrees or more, causing it to shine in X-rays.
The other source, dubbed NGC 300 ULX1, was originally identified as a supernova explosion in 2010. However, later observations prompted astronomers to reconsider this interpretation, indicating that this source also conceals a binary system comprising a very massive star and a compact object – a neutron star or a black hole – feeding on material from its stellar companion.
Data obtained in 2016 with ESA’s XMM-Newton and NASA’s NuSTAR observatories revealed regular variations in the X-ray signal of NGC 300 ULX1, suggesting that the compact object in this binary system is a highly magnetized, rapidly spinning neutron star, or pulsar.
The large blue blob in the upper left corner is a much more distant object: a cluster of galaxies more than one billion light years away, whose X-ray glow is caused by the hot diffuse gas interspersed between the galaxies.
Einstein predicted that time slows down the faster you travel and the time-dilation hypothesis has since been proven by flying atomic clocks on aircraft.
The three fastest human beings at the moment are NASA astronaut Anne McClain, Canadian Space Agency astronaut David Saint-Jacques (pictured) and Roscosmos astronaut Oleg Kononenko who are orbiting Earth on the International Space Station at a speed of around 28 800 km/h.
They are travelling so fast that they will return home to Earth after their six-month spaceflight 0.007 seconds younger than if they had stayed with their feet on the ground.
But how do astronauts perceive time in space? Space Station crew report that time seems to speed up in microgravity so European researchers are trying to find out more by immersing astronauts in virtual reality and testing their reaction times.
A virtual reality headset is used to block external visual cues that could influence the results. The experiment focuses on how astronauts estimate time duration as well as their reaction times. They are asked gauge how long a visual target appears on screen. Their reaction times to these prompts are recorded to process speed and attention.
The astronauts run the experiment before flight, on the International Space Station and again when they land to compare results. ESA astronaut Alexander Gerst was the first test subject to take part in this experiment in 2018. Anne and David did a session in February in ESA’s Columbus laboratory.
Understanding how time is perceived in space is important as astronauts are often required to conduct precision work where timing is everything. This research in microgravity will help reveal clues as to what helps keep our brains ticking the seconds accurately.
A colourful microscopic view of a single piece of space-quality Inconel super alloy processed using two different 3D printing techniques; this is a close-up of the boundary layer between them.
The left side was produced using ‘direct energy deposition’ based on laser melting of metal powder feedstock, while the right side was made through ‘powder bed fusion’, involving the deposition then melting of metal powder.
This micrograph of the resulting hybrid part is based on a technique called electron backscatter diffraction. An electron beam was reflected off the crystalline metallic surfaces to reveal subtle details of their composition. The patches reveal different grains and the various colours depict the differing orientations of these grains.
ESA is working with research institutes and companies across Europe on its Advanced Manufacturing initiative, harnessing 3D printing and other emerging manufacturing techniques to change the way space missions are made.
The Copernicus Sentinel-2B satellite captured this true-colour image on 5 February 2019, just three days after heavy rainfall in Rome and the surrounding area of Lazio, Italy. It shows sediment gushing into the Tyrrhenian Sea, part of the Mediterranean Sea. The downpour on 2 February led to flooded streets, the closing of the banks of the Tiber River and several roads.
The Tiber River can be seen snaking its way southwards in the image. The third longest river in Italy, it rises in the Apennine Mountains and flows around 400 km before flowing through the city of Rome and draining into the sea near the town of Ostia. The Tiber River plays an important role in sediment transport, so coastal waters here are often discoloured. However, the recent rains resulted in a large amount of sediment pouring into the Tyrrhenian Sea, as this image shows. The sediment plume can be seen stretching 28 km from the coast, carried northwest by currents.
Copernicus Sentinel-2 is a two-satellite mission. Each satellite carries a high-resolution multispectral imager to monitor changes in vegetation. It also provides information on pollution in lakes and coastal waters.
The ExoFit model of the Rosalind Franklin rover that will be sent to Mars in 2021 scouting the Atacama Desert, in Chile, following commands from mission control in the United Kingdom, over 11 000 km away.
The ExoFiT field campaign simulates ExoMars operations in every key aspect. During the trial, the rover drove from its landing platform and targets sites of interest to sample rocks in the Mars-like landscapes of the Chilean desert.
The team behind the exercise, a mix of scientists and engineers, is simulating all the challenges of a real mission on the Red Planet, including communication delays, local weather conditions and tight deadlines.
The rover is equipped with a set of cameras and proxy instruments, such as a radar, a spectrometer and a drill, to replicate martian operations.
Scientists in the UK must take decisions on the next steps with the little information they have – a combination of the data transmitted by the rover and satellite images of the terrain.
The ExoFiT teams in the UK set the exploration path and activities for the rover, which travels at a speed of two centimeters per second avoiding rocks and overcoming slopes.
ExoFiT stands for ExoMars-like Field Testing, and it is an essential step to improving European robotic operations not only for ExoMars, but also for future missions aiming to return soil from the Red Planet, such as the Mars Sample Return mission.
Globular clusters like NGC 2419, visible in this image taken with the NASA/ESA Hubble Space Telescope, are not only beautiful, but also fascinating. They are spherical groups of stars which orbit the centre of a galaxy; in the case of NGC 2419, that galaxy is the Milky Way. NGC 2419 can be found around 300 000 light-years from the Solar System, in the constellation Lynx (the Lynx).
The stars populating globular clusters are very similar to one another, with similar properties such as metallicity. The similarity of these stellar doppelgängers is due to their formation early in the history of the galaxy. As the stars in a globular cluster all formed at around the same time, they tend to display reasonably homogeneous properties. It was believed that this similarity also extended to the stellar helium content; that is, it was thought that all stars in a globular cluster would contain comparable amounts of helium.
However, Hubble’s observations of NGC 2419 have shown that this is not always the case. This surprising globular cluster turns out to be made up of two separate populations of red giant stars, one of which is unusually helium-rich. Other elements within the different stars in NGC 2419 vary too — nitrogen in particular. On top of this, these helium-rich stars were found to be predominantly in the centre of the globular cluster, and to be rotating. These observations have raised questions about the formation of globular clusters; did these two drastically different groups of stars form together? Or did this globular cluster come into being by a different route entirely?
Week in images
25 February - 1 March 2019