Welcome and Notices Ian Bradley

Ian welcomed members and announced notices:

• A 4″ refractor has been offered sale – contact for details through the website
• An all-day, Saturday 7th of September, Astronomical event hosted by the Preston and District Astronomical Society see our calendar for neighbouring events.
• Our EAS monthly meetings are moving to the first Thursday of the month after the New Year.

Sky Notes for September 2019 – David Glass

See our Sky Notes for September 2019

David’s proposal of a visit to Alston Observatory, Preston was accepted. Meet at 7:30 PM on Tuesday 29th October. A meal at the Black Bull immediately before will be optional.

Astronomy News Phil Morris

Hayabusa2 on the Asteroid Ryugu

The Mobile Asteroid Surface Scout (MASCOT) has been deployed 41m above the surface on a 17-hour mission to measure the structure, distribution and texture of the surface of asteroid Ryugu. See also What asteroid Ryugu told us

Jupiter

The Juno spacecraft orbiting Jupiter has discovered a new spot (aka Great Blue Spot) beneath the opaque clouds on the first definite detection of an extra-terrestrial planetary, magnetic field. The Juno mission will end in 2021 after which the next mission to Jupiter, to Jupiter’s moons in fact) may well be called JUICE (JUpiter ICy moon Explorer) .

Hubble Space Telescope

The Hubble space telescope has been involved in measuring the rate of expansion of the universe, the Hubble Parameter, H . Current measurements from

• the Cosmic microwave background (CMB) give H = 67.4
• the apparent brightness of Supernovae Type 1a gives H = 72
• Hubble recently measuring the distances to red giant stars H = 68.8

Steps are underway to measure the value using gravitational waves – see our Guest Speaker’s talk in October.

Supernovae

The Gaia galaxy-mapping telescope has detected a new type of exploding Supernovae. It seems to be on the periphery of the galaxy, not at its heart. Its mass has been calculated as 200 times that of the sun Its spectrum is different from that of any other supernovae yet detected It seemed to explode twice.

Such massive supernovae have been predicted and the final explosion may involve anti-matter obliterating the star without leaving a black hole .

Dalby Star Camp – Moira Greenhalgh and Richard Rae

Moira and Richard had returned from the Dalby Start Camp on the day of the meeting. A weekend star camp was highly recommended for:

• dark skies
• lectures
• access to many types of equipment
• with your own equipment

Volcanic Processes on Mars Professor Lionel Wilson

Professor Wilson gave an illustrated talk on volcanism Mars often comparing the processes with the volcanism on the Earth. Differences in the Mars environment such as:

• lower gravity field
• lower air pressure
• lack of mobile plate tectonics

explain many of the martian features such as higher and more massive volcanoes (on average twice the size) and the predominance of low profile Shield volcanoes that have a 10 -100 million year history – being less mobile and less degraded by weather – and occur to be in non-linear formations. The evidence of large scale lava flows, in both quantity and flow rates, needs more geological causes, such as low viscosity of the lava. Recent work has been on the distant rills similar to glacial rills on the continent of Antarctica and the discovery of bulges higher, than the volcano caldera , that are being pushed upwards by the large, underground magma chambers that also create subsidiary, lateral outflows and eruptions. For more information see:

• depressed blocks of crust from Graben collapse
• higher plasticity on Martian Pyroclastic flows
• Martian soil characteristics
• Geology of Mars