Space Sunday: an eclipse, a space ship, lasers and a birthday

The total lunar eclipse as seen over the columns of the acropolis. Greece, on July 27th, 2018. Credit: Valerie Gache / AFP Getty Images

Friday, July 27th marked the longest lunar eclipse of the 21st century, which was visible from southern Africa, Australia, and Madagascar, Europe, South Asia and South America. Although many of us in the UK largely (and typically!) missed out, as the summer heat wave gave way to rain and clouds, a bit of a double blow, given we were just outside the reach of totality.

For about half the world, the Moon was partly or fully in Earth’s shadow from 17:14 to 23:28 GMT; six hours and 14 minutes in all, with the period of totality – when the Moon lies entirely within the Earth’s shadow, and so is at its darkest – lasting from 19:30 to 21:13 GMT.

Another view of the eclipse from Greece: the Moon appears between the ancient gods Apollo and Hera in Athens. Credit: Aris Messinisaris / AFP / Getty Images

In a special treat, Mars, which is currently at opposition, sitting on the same side of the Sun as Earth, and thus at its closest to Earth (roughly 92 million km /  57 million mi), was visible just below the eclipsed Moon, appearing as a bright “star”. Those blessed with clear skies also had the treat of Saturn, Jupiter and Venus being visible in the sky as well.

The reason the eclipse lasted so long was that the alignment between Sun, Earth and Moon meant that the Moon was passing right across the middle of the disc of shadow cast by the the Earth. This also meant this eclipse created a particularly strong blood Moon. This is a phenomena caused by the lensing effect of the Earth’s atmosphere scatters blue light from the Sun outwards, whilst refracting red light inwards, so the Moon appears rusted as  seen from Earth.

The July 2018 blood moon, seen from Siliguri, India, on July 28th, 2018 (local time). Credit: Diptendu Duttadiptendu Dutta / AFP /Getty Images

Virgin Galactic Reach Mesosphere for the 1st Time

VSS Unity took to the skies on July 26th, 2018, and reached its highest altitude yet: 52,000 metres (170,800 ft), the highest any Virgin Galactic vehicle has thus far reached.

VMS (Virgin Mother Ship) Eve, the WhiteKnightTwo carrier aircraft, took off from the Mojave Spaceport at 15:45 GMT and climbed to an altitude of 14,000 metres (46,500 ft), prior to releasing Unity, which dropped clear prior to its single rocket motor being ignited. The engine burned for some 42 seconds, powering the vehicle into a near vertical ascent and a speed that reached Mach 2.47.

This was enough to propel Unity on a parabolic flight that topped-out at 52,000 m, inside the mesosphere, which spans heights from approximately 10 km (33,000 ft; 6.2 mi) to 100 km (62 mi; 330,000 ft), representing the heights to which Virgin Galactic flights will typically carry fare-paying passengers so they can enjoy around 5 minutes of weightlessness.

VSS Unity mid-flight on July 26th, 2018, as seen from a chase plane. Credit: Virgin Galactic / / Trumbull Studios

It was a thrill from start to finish. Unity’s rocket motor performed magnificently again, and Sooch [co-pilot Mike Masucci] pulled off a smooth landing. This was a new altitude record for both of us in the cockpit, not to mention our mannequin in the back, and the views of Earth from the black sky were magnificent.

– Virgin Galactic’s chief pilot, Dave Mackay

The mesosphere is sometimes referred to the “ignorosphere”, as it sits above the range of instrument carrying balloons, but well below the height from which it can be studied from space, and so remains one of the least-studied parts of the atmosphere. As well as carrying passengers aboard their vehicles, Virgin Galactic plan to change this by also flying experiments up to the mesosphere that might be used to probe it.

VSS Unity about to touch down, July 26th, 2018. Credit: Virgin Galactic

As with previous flights, today’s test flight was designed in part to gather additional data about conditions in the cabin during flight, but it also marks a significant step closer to the company starting commercial tourist flights, which are currently earmarked to commence in 2019, or possibly the end of 2018. Before that, however, the company will make at least one flight  with Unity’s motor fuelled for a full duration burn of 60 seconds. When that might be, and whether it might follow  directly on from this flight (which represented an 11 second longer engine burn than previous flights) or be worked up to, has yet to be stated.

When operational, VSS Unity will be joined by at least two more SpaceShipTwo vehicles, and – at some point in the next couple of years – an additional WhiteKnightTwo carrier vehicle, given the company are looking to operate flights out of Italy as well.

Images Worthy of Hubble – From the Surface of the Earth

The four Unit Telescopes of the Very Large Telescope, operated by the European Southern Observatory (ESO),pictured ar sunset and about to start a night’s work. Credit: ESO

The Very Large Telescope (VLT) is perhaps the world’s most advanced ground-based optical telescope. Operated by the European Southern Observatory (ESO) high in the Atacama Desert, northern Chile. VLT comprises what are referred to four Unit Telescopes, each with a primary mirror 8.4 metres (27.6 ft) across, all working individually or in concert, and supported by four 1.8 m (6 ft) diameter Auxiliary Telescopes.

Having entered service in 2007, VLT was recently upgraded with a new instrument known as the Multi Unit Spectroscopic Explorer (MUSE), a panoramic integral-field spectrograph that works at visible wavelengths, and which can take full advantage of the VLT’s adaptive optics mode.

The four GALACSI lasers see “first light” – the first time they are fired – following their installation and calibration on UT4 of the VLT. Credit; ESO

Adaptive optics is an astronomical technique that allows instruments to compensate for the influence of the Earth’s atmosphere in scattering and distorting light, resulting in blurred images of distance objects (as well as causing the stars to “twinkle” to the naked eye). Images captured using adaptive optics are far clearer and more focused that otherwise would be the case.

The new MUSE instrument adds a new capability to VLT, referred to as GALACSI, mounted on one of the four Unit Telescopes. Comprising four lasers fixed to the Unit Telescope to fire intense orange light into the sky. These beams simulate sodium atoms high in the atmosphere to create artificial “Laser Guide Stars”. Light from these artificial stars is then used to determine the turbulence in the atmosphere and calculate corrections, which are then used to correct atmospheric distortions in the light captured by the telescope.

Neptune as seen by the VLT using the narrow field adaptive optics mode of MUSE / GALACSI in mid-July 2018. Credit: ESO / P. Weilbacher (AIP)

The system can be operated in two modes: wide field and narrow field, the latter of which allows the system to almost completely eliminate all effects of atmospheric distortion, producing remarkably clear and striking images of solar and stellar objects. Just how  striking can be seen in the image of Neptune, above, released by ESO earlier in July 2018. It reveals Neptune’s atmosphere in startling detail.

Using MUSE with GALACSI, the VLT can not only produce images like the one of Neptune, it can  probe deep space, the spectrograph able to dissemble the visible light of distant objects, allowing scientists to further probe their secrets.

Comparative images: a 1994 image of Neptune by the Hubble Space Telescope in 1994 (NASA / ESA), and the image captured by the VLT using MUSE / GALACSI (ESO)

The technique is referred to as laser tomography, and VLT will not be the only ESO telescope to gain it. ESO’s Extremely Large Telescope (ELT), currently under construction will also be equipped with the capability, based on the work done at the VLT. ELT will use laser tomography as a central means of accomplishing its scientific goals, which include the study of super-massive black holes (SMBHs) at the centres of distant galaxies, the jets from young stars, globular clusters, supernovae, the planets and moons of the Solar System, and extra-solar planets.

Comparative images by VLT. On the left, Neptune as seen by the telescope with the adaptive optics capability turned off. On the right, Neptune seen with the MUSE/GALACSI adaptive optics system active in its narrow field mode. Credit: ESO

Happy 60th Birthday NASA!

On  on July 29th, 1958, sixty years ago from the date of this article, President Dwight D. Eisenhower signed the National Aeronautics and Space Act, calling into existence the US National Aeronautics and Space Administration, NASA – although the agency did not become operational on October 1st, 1958 (which might be regarded as its “official” birthday).

NASA’s 60th anniversary logo. Credit: NASA

While NASA has led the US government’s civilian space endeavours, it originally came into being as a matter of national security. In 1957, Russia launch the Sputnik satellite, to be followed by two more in 1957 and 1958.

One of the key players in NASA’s formation was Legislative Reference Service analyst Eilene Galloway. She was tasked by (then) Senate Majority Leader (and later President) Lyndon B. Johnson to summarise Congressional hearings on America’s approach to space in the wake of fears concerning Soviet dominance.

Her report,  The Problems of Congress in Formulating Outer Space Legislation provided testimony from both the military and – particularly – civilian scientists who were concerned that space might become the preserve of the military to the exclusion of scientific research. It held several recommendations, but pointed towards the creation of a new civilian agency to lead America’s space efforts, helping to pave the way for NASA to come into existence.

Galloway went on to be regarded as America’s “Grand Dame of Space”, becoming an influential force in the development and analysis of US domestic and international space law and policy.

It was almost as if a bomb had fallen on Capitol Hill. We were so surprised that the Soviet Union was first. Both the United States and the Soviet Union had space projects in the International Geophysical Year, but our project was very small. It was a satellite that weighed a little more than three pounds, and the Soviet satellite [weighing around 184 lbs /83.5 kg] really opened up outer space as the new environment, added to land, sea and air.

– Legislative Reference Service analyst Eilene Galloway

The bill Eisenhower signed on July 29th, 1958 established eight objectives for the new National Aeronautics and Space Administration, namely:

  1. The expansion of human knowledge of phenomena in the atmosphere and space;
  2. The improvement of the usefulness, performance, speed, safety, and efficiency of aeronautical and space vehicles; Tea
  3. The development and operation of vehicles capable of carrying instruments, equipment, supplies, and living organisms through space;
  4. The establishment of long-range studies of the potential benefits to be gained from, the opportunities for, and the problems involved in the utilisation of aeronautical and space activities for peaceful and scientific purposes;
  5. The preservation of the role of the United States as a leader in aeronautical and space science and technology and in the application thereof to the conduct of peaceful activities within and outside the atmosphere;
  6. The making available to agencies directly concerned with national defence of discoveries that have military value or significance, and the furnishing by such agencies, to the civilian agency established to direct and control non-military aeronautical and space activities, of information as to discoveries which have value or significance to that agency;
  7. Cooperation by the United States with other nations and groups of nations in work done pursuant to this Act and in the peaceful application of the results thereof;
  8. The most effective utilization of the scientific and engineering resources of the United States, with close cooperation among all interested agencies of the United States in order to avoid unnecessary duplication of effort, facilities and equipment

Although the Act has been amended over the years, these eight objectives still describe the major functions of NASA today.

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