香港六合彩中特网

carries out a wide range of research in the area of space weather. From looking at how the Sun produces the most energetic eruptions and explosions in the Solar System to studying how these events drive processes such as the aurora and ultimately cause disruptions to our satellite services, communications and electricity distribution.

Popularised in the 1990s, the term 鈥淪pace Weather鈥� describes the conditions in space, near the Earth, governed by the Sun鈥檚 constant release of charged particles known as the 鈥榮olar wind鈥�. Periods of peak solar activity give rise to what are called 鈥榮evere space weather events鈥�, where the Sun produces phenomena such as solar flares and coronal mass ejections (CMEs) that interact with the Earth鈥檚 upper atmosphere and surrounding magnetic field, often to dramatic effect.

Professor Louise Harra, Head of the Solar Physics Group at MSSL, is currently working on Hinode (a Japan/US/UK space mission) as Principal Investigator for the Extreme-Ultraviolet Imaging Spectrometer (EIS). Built by an MSSL-led consortium, the EIS measures the flow velocity of solar particles, as well as the temperature and density of the solar wind.

鈥淗inode, which means sunrise in Japanese, has been described as the Hubble telescope of the Sun,鈥� says Harra. 鈥淚t observes the surface of the Sun in great detail, seeing where magnetic fields have been created and how those produce the activity that we see.鈥�

鈥淪olar flares are very fast releases of energy across pretty much the whole electromagnetic spectrum, while coronal mass ejections are these huge bursts of mass and magnetic field.鈥�

Together, Harra explains, the two phenomena are the most dramatic aspects of space weather in terms of their effect on Earth. 鈥淪olar flares happen quickly and they鈥檙e very energetic, so you will get an impact from one within tens of minutes potentially. You鈥檒l get particles accelerated to close to the speed of light that can come and hit the near-Earth environment.

鈥淐oronal mass ejections take a couple of days to get here, but, again, those can have a big effect in the near-Earth environment where there are spacecraft orbiting the Earth.鈥�

And should solar flares or CMEs reach Earth, a different scientific skillset will be required. This is where Dr Robert Wicks, joint lecturer at MSSL and the , comes in.

鈥淲e have a lot of expertise in space physics, the activity of the Sun and its impact on the Earth at MSSL,鈥� he says. 鈥淏ut at MSSL we generally don鈥檛 have a huge amount of expertise in resilience, planning and risk鈥娾�斺�奍RDR does have such expertise. So I鈥檓 trying to form that link to enable us to be leaders in the UK on preparedness and resilience for space weather.鈥�

MSSL is also involved with a European Space Agency (ESA) mission to help reduce the global risk of damage caused by space weather, which will be worked on by teams from across the UK with 香港六合彩中特网 playing a pivotal role in developing instruments on board the spacecraft.

The Lagrange mission would have a 鈥榮ide view鈥� of the Sun and provide advance warning hours or days before solar active regions 鈥� often the source of energetic flares or CMEs 鈥� rotate into view of Earth. MSSL is leading the development of a set of instruments to assess the environment around the Lagrange spacecraft, including a sensor that will measure the charged particle plasma ejected by the Sun.

In 2017 香港六合彩中特网 launched their first satellite, CubeSat, which will orbit from between six months to two years聽at a height of 375 - 500 km.聽

Until now, Earth's thermosphere has only been studied in situ for minutes at a time using rockets. This is because the thermosphere is too near to the surface to send expensive satellites that would get pulled down by drag within six months, and it is too high for balloons and planes.

CubeSats, such as 香港六合彩中特网Sat, are an ideal solution as they are relatively cheap (a hundred thousand dollars compared to a few hundred million dollars of traditional space agency satellites) and are small enough to stay in orbit for up to two years. Together they will monitor the thermosphere over a range of altitudes. While in their decaying orbits, they will measure the chemical composition and particle and electron densities.

Dr Anasuya Aruliah (香港六合彩中特网 Astrophysics) who will be analysing the data collected from 香港六合彩中特网Sat, explained: "Scientifically this is a unique experiment. For the first time we will have several months of simultaneous measurements of the thermosphere from many locations. We hope for detailed investigations of how solar flares and the solar wind influence the dynamics and chemistry of the upper atmosphere, and the risk to satellites and technology."

Links

• Mullard Space Science Laboratory
• 香港六合彩中特网's first satellite '香港六合彩中特网Sat' launched
• Space Risk and Disaster Reduction MSc

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