Notes and Links from the September Meeting

Chairman’s announcements

The chairman welcomed the Dark Skies Project Officer for the Friends of the Lake District and asked for volunteers to be a liaison to work for dark Sky Accreditation. A communication from Ullswater Yacht Club who are looking to open their grounds for the use of members. Members were notified of UCLAN public lectures in Lancaster and Preston during October 2018. Members asked to finalise their requests to visit Alston Observatory after the next meeting on Tuesday 2nd October.

Astronomical News

Two news roundups were given by two members. Galaxy news links: Solar Orbiters: Miscellaneous items

More Astronomical News

The Ecliptic

Arising from question Why Mars farther than other planets from Ecliptic last year. Planetary orbits are inclined to the ecliptic plane by up to 6° (maximum reached by the planet Mercury). The Ecliptic coordinate system, Celestial equator, Ecliptic and Celestial poles were covered as well as equinoxes.

Not to be confused with the orbit shape ‘ecliptic’ the word comes from the fact that when the moon crosses the ecliptic we experience an eclipse.

Sky Notes for September

From the Ecliptic the meeting was focused to the constellations near to the Zenith, where starlight travels through the minimum depth of atmosphere to the telescope. By the middle of September, we will be experiencing 7 hours of Astronomical Dark from 9 PM. See Sky Notes in particular.

Guest speaker, Stuart Atkinson Famous Fake Astrophotos

Stuart gave an entertaining but informative talk that also warned of the dangers of false attribution of astrophotographs taken by members. Since the advent of digital cameras and post-processing software images are not only easy to fake, as opposed to the valid enhancement of target features. In addition, the internet has released a Pandora’s Box where the distribution fake images become impossible to control. Images were illustrated from obvious Artistic impressions being passed off as factual to the deliberate stealing of images. For the latter, defences were outlined such as ‘Watermark’ signing to the proven method of introducing errors.

Notes and Links from the August Meeting

Chairman’s reports

This Saturday, 11th August the Perseid meteor shower will occur on a moonless night. However, the forecast at the moment is poor.

Astronomical News

  • Members may still join arrangements for a second visit to Alston Observatory is being organised for Tuesday 2nd October
  • The NASA Parker Solar Probe is due to be launched this Saturday 11th August. The probe will fly into the solar corona and will investigate the Solar wind and the heating of the solar corona to very high temperatures.
  • A pair of images of Neptune illustrated the gain in using new Adaptive Optics by the VLT. The images demonstrate that the VLT with the latest adaptive optics can be competitive with the Hubble Space Telescope. The new technology is also applicable to the future 40m-class telescopes (e.g. the E-ELT) and is essential to get the best out of these new assets.
  • The MeerKAT interferometric radio telescope in South Africa can now produce science images. An image of the centre of the Milky Way was shown, which reveals new detail of unexplained filaments in the region.

Orbital Physics and Spacecraft Manoeuvring

A member gave an Illustrated talk and demonstration to explain an orbit: throw hard enough until your ball goes over the horizon and continues to fall towards the planet at the same rate as the ground ‘falls away’ due to the curvature of the planet resulting in a circular orbit. The problem of manoeuvring without changing orbits was illustrated with the failed docking scheduled for Gemini 4 before their first spacewalk. From a distance, increasing speed by the trailing vehicle changes the vehicle’s trajectory into a higher and more elliptical orbit.

Olber’s Paradox

  Why is the night sky dark?   A member’s talk described the paradox attributed to  Heinrich Wilhelm Olbers ( 1758–1840).  Given an infinite number of stars that compensate intensity decrease with distance, the night sky should light. Although the Big Bang specifies that the material in the universe is finite, there are more than enough galaxies to cover one per a pixel on telescopes in the foreseeable future making the paradox still valid. The currently the solution accepted is that space is expanding: thus, cooling radiation and shifting radiation towards the red and radio. Other explanations are also mooted.

Explanatory solution addendum added by a member:

Infinite or not, the universe is of a size that means that even travelling as fast as they do, photons from some distant stars have yet to reach us. There will certainly be some redshift arising from the expansion of the universe, but this effect can be ignored by recasting the paradox in terms of radiation generally, rather than the much smaller visible spectrum. So irrespective of wavelength, the paradox is why there is not an infinite bath of radiation. The “fractal” explanation is a way round the homogeneous assumption inherent in the paradox, and as in the talk, the fractal calculations of the universe diverge from the required dimension. So I think we’re left with the “it hasn’t reached us yet” solution. And, of course, it never will reach us – but that’s a different talk.

Telescope Mount Alignment

The types of astronomical telescope mounts were explained by a member:  Altazimuth  and  Equatorial . Current ‘GoTo’ software offers the opportunity to iterate polar re-alignment. How accurately does the polar alignment need to be for time exposure photography? After much work and many calculations , our member discovered that the error reported by the software, for the polar misalignment, may be used as the drift across the image in 24 hours. Hence the rate of drift can be quickly calculated. The pixel coverage for a given camera together with the focal length of the system can be used to determine the sky coverage per pixel, eg 2 arc seconds/pixel. The rate of drift can then be used to determine the time to drift across one pixel (or maybe more) to find the maximum exposure time for the reported polar alignment error. In summary, tolerance for the error in polar alignment can be calculated beforehand. The telescope polar alignment procedure can then cease when within the desired tolerance.  

Notes and Links from the July Meeting

Chairman’s reports and sky notes

See Sky Notes. In particular:

  • There will be no actual astronomical darkness until August as the sun skims under our South Lakes horizon.
  • The moon will rise on Friday 27th July at 21:12 already in the maximum phase of a total lunar eclipse – see data for the lunar eclipse for Kendal 27th July
  • During the latter part of July, all the visible planets will be in the night sky from Kendal although Mercury will be too close to the sun to observe

Astronomical News

A second visit to Alston Observatory is being organised for Tuesday 2nd October

The JAXA spacecraft Hayabusa 2 successfully arrived at the asteroid 162173 Ryugu, on 27 June due to return material from the asteroid to Earth by the end of 2020. See also: Astro Bob.

Two new methods of detecting exoplanets in the news:

  • by detecting disturbances in the molecular gas (carbon monoxide) within the protoplanetary disc using ALMA
  • by direct imaging using a occulting coronagraph and adaptive optics with the  ESO’s Very Large Telescope (VLT) discovered the first planetary accretion disc 

Comet imaging in Stereo

One of our members presented images of comets which may be viewed through a Stereograph. The main obstacle to Astro-stereo images is determining an adequate separation between two simultaneous images. Images were displayed that had used overlapping times from a telescope in Spain and a telescope in South America. Also, a stereograph was available during the break to view a video gif of the displacement of a close-approach comet imaged from the Earth at two different times. 

Guest speaker Professor Jim Wild, Weathering Solar Storms

Professor Wild gave an illustrated talk that progressed from the physics of solar storms, through a history of destructive storms to current developments to defend against the effects of a violent storm of electrically  charged particles on our society dependent on electricity, electronics and satellite transmissions not forgetting long-distance space travel out of the Earths protecting magnetic field..

A sequence of early photographs of a comet showed the effects of a solar storm passing by in the background. Current forecasting of the arrival of one of the many storms from the sun is made difficult by only be able to view an approaching storm head-on, compared with the numerous meteorological stations used for weather forecasting, A number of satellites are planned to be placed in the Lagrangian points (parking places) relative to the Earth and the Sun that would be able to detect approaching storms from side-on.

Implications for exoplanets were highlighted.  A necessary condition for a planet to sustain life (see Goldilocks Zone) is that the planet must have a magnetic field – that will protect from charged particles released from the parent star.

Notes and Links from the June Meeting

Chairman’s reports and sky notes

See Sky Notes. In particular:

  • There will be no actual astronomical darkness until August as the sun skims under our South Lakes horizon.
  • Venus, just after about 10:30 PM, is at the bright magnitude -4 above the western horizon near the crescent moon on the 16th June.
  • Jupiter is visible from sunset to sunrise, starting low in the south-east.
  • Saturn will rise with the full moon late in the month.

Astronomical News

Links to the items raised:

Variable star photometry

One of our members presented results taken over two nights of measuring the light detected from two stars, using a QHY163c CMOS astro camera connected to a 10″ telescope, compared to the light received from nearby comparison stars of known magnitude – the technique known as differential photometry. The first star was a well known contact binary star system V523Cas (with a magnitude change of ~0.9 magnitudes) which acted as a useful and successful testbed for the photometry system. The low noise permitted the second study – the attempt to detect the transit of planet across the face of a distant star from a Kendal backyard. An online search (http://var2.astro.cz/ETD/predictions.php) on the next clear night, 10 December 2017, suggested the excitingly labeled XO-6b with a relatively large magnitude change of 0.013 magnitudes. This 10 magnitude star, 270 light years away, was measured over an evening of deteriorating conditions. The sky conditions deteriorated so badly that all stars dimmed by 50%!

The change in brightness signal of the target star, blue, and three potential comparison stars during the night of the observations.

Nevertheless, comparisons with light levels from neighbouring stars indicated a 1.2% diminution of the light from the target star. The diminution is caused by an exoplanet, twice the size of Jupiter at 8% of Earth’s orbit radius, that transits the star approximately every four days. The timing and dip in brightness occurred at both the right time and expected size.          

Smoothed magnitude change for the exoplanet transit across the face of the star XO-6b.

Telescope Night (outside)

The second half of the evening was spent outside in the Museum grounds under a blue sky. Members and guests milled around asking questions and demonstrating their own telescopes, mounts and software.

Notes and Links from the May Meeting

Guest speaker: Professor Ian Robson Confessions of an Astronomer”

Professor Ian Robson gave a light-hearted talk covering his career in astronomy from a telescope on the top of Queen Mary University above a London street in the 1960’s to the top of a snow-drifted Mauna Kea, Hawaii – including frequent, confessional asides. Some aspects may have been expected, such as bids for project finance and student and graduate applications on a professor’s desk. Less expected were the thousands of air miles accumulated over a lifetime in astronomy.

Prof Robson has written a book demonstrating the connections between observations and theory: Active Galactic Nuclei

Member’s Talks

Sky and Society Notes for May

See Sky Notes. In particular:

  • Venus at the bright magnitude -3.9 in the evening presents a three-parts, waxing gibbous phase visible in small telescopes.
  • Jupiter is visible from sunset, starting low in the south east.
  • Full astronomical darkness will not occur again until August.

Major night sky imaging proposal

The society has been offered the opportunity to participate in a world wide public outreach project using the Las Cumbres Global Telescope Network. Our choice of target is likely to be the Hyades cluster in Taurus. Of significance to EAS, the displaced positions of Hyades stars were those measured by Sir Arthur Eddington during the 1919 Solar Eclipse  confirming Einstein’s General Theory of Relativity.

Kendal Outreach

Volunteers to present are just about enough to hold the proposed Solar System in Kendal event on Saturday 18th August.

The Constellation of the Month

Our regular member’s presentation of Constellation of the Month featured the low, summer constellation of Virgo. Leo was also included.

Astronomical News

NASA successfully launched their Insight Mission a week ago to arrive on Mars in two months time. Over the following Mars-year (approximately 1.5 Earth years) the mission lander will probe the surface with a seismometer and then wait to measure the vibrations from any subsequent seismic events.

The upper atmosphere of an exoplanet (WASP-107b) has been analysed using the light filtered through it during a transit, revealing the (not unexpected) presence of Helium. Work to test the method on Earth’s atmosphere (Yan et al. 2014) proved that atmospheric compositions can be studied in this way and that significant biomarkers (oxygen, water, NO2) can be detected. They analysed the light that passed through Earth’s atmosphere and bounced off the moon during a lunar eclipse.

The universe expands with distance at a rate which is given by the Hubble Constant – or are there two Hubble Constants? 68 km/sec or 73 km/sec – or, even, both. Measurements have been made using the structure of the early Universe and using ‘standard candles’ in galaxies as in our February guest speaker’s research. The values obtained by the two methods appear to be different, and the chance that the difference is a fluke is currently less than 0.01%. This is nearly at ‘discovery’ level but not quite. If the difference is true, it may point the way to new physics or an overhaul of cosmological models. In the words of our member: ‘Over to the Cosmologists to sort this one out’.

Notes and Links from the April Meeting

Sky and Society Notes for April

See Sky Notes in particular.

Major night sky imaging proposal

The society has been offered a one-hour imaging session of an astronomical object of their choice on the  Las Cumbres Global Telescope Network . The offer has come from Carl Pennypacker, one of the teams whose studies of supernovae led them to infer in 1998 the existence of dark energy driving the expansion of the universe.    The society is keen to involve any members who wish to engage with this imaging project, including local schools if appropriate.  We have until December to choose an object and conduct the imaging. Please get in touch here if you would like to be part of this project, or if you have any suggestions for imaging targets.

UCLAN lecture

The meeting was reminded that the upcoming event at UCLAN in Preston:  The Jeremiah Horrocks Spring Lecture Comets, Asteroids and Impacts. Should we worry and what can we do? Tuesday 15th May 2018 – 6:30 pm.

Kendal outreach

More volunteers are required for a few hours during the proposed Solar System in Kendal  event on Saturday 18th August.

Other events

The next Member’s Observing evening will be in autumn when dark nights return.

The next public Moonwatch will be on Saturday 24th November

Member’s photographs

The Horsehead Nebula in Orion One member demonstrated an impressive difference in colour hues using  Pixinsight on the Horsehead Nebula  Not cheap software package but highly recommended for colour correction using a star catalogue. Now listed on our Links page under  Software used by members

Astronomical News

The farthest star ever detected has been imaged by the Hubble telescope, a Blue Giant in a galaxy nine billion light years distant:  Hubble Uncovers the Farthest Star Ever Seen. Forget the  Kepler space mission , a  recent paper  encourages more enthusiastic, if not radical, members to use their standard DLSR cameras to join in the search for exoplanets.

Guest speaker Robert Ince  Widefield and time-lapse astrophotography”

After answering to a professional career migrating from explosives to his lifetime interest in Astronomy, Robert Ince illustrated his personal revival of astrophotography with a camera only – without his 12″ telescope. Beginning with landscapes with star backgrounds and star trails, the talk progressed through driven exposures, including time-lapse video and panning sequences, to the use of filters.  Robert described in detail his post-exposure processing using a wide range of software. A number of useful links were listed:

The links above are now on our  Software used by members

Moon, Venus, Mercury conjunction…

19th March saw us heading for Helsington Church to catch this conjunction of three heavenly bodies, under the impression that the forecast was going to deliver a clear sky.  Well, I think this photo from Ted Woodburn sums it up – all three were visible at some point during the evening, but not necessarily at the same time!

Still, a good time was had by all who came out to see…

Notes and Links from the March Meeting

Sky Notes

See Sky Notes in particular: Sunday 11th when the Moon and Saturn rise together, Monday 19th when the Moon, Venus and Mercury set together – suitably viewed from the Scout Scar mushroom and Helsington church grounds, Saturday 24th for the EAS public Moonwatch at the Brewery when the crater Plato will be casting shadows from the terminator division between lunar night and day and see late night 27th for Astronomical gamblers.

 

Astronomical News

See SpaceX landing video for the SpaceX landing.

Astrobites has been added to our links page joining Sky & Telescope and Astronomy Now

Guest speaker Dr Anne Sansom on Dust in Early-Type Galaxies

Dr Sansom discussed the presence of dust in early-type galaxies (lenticulars and ellipticals), and what that can tell us about how these galaxies formed and evolved. Dust is an indicator of what has happened in a galaxy over its life and can be added by galaxy mergers or stars as they age, and is destroyed over time, so how much dust is present can reveal much about what has happened to a galaxy over its life.

Much of the work comes from the Herschel-ATLAS survey, the Galaxy and Mass Assembly (GAMA) project for three specific areas of the sky, and the Herschel Virgo Cluster Survey (HeVICS). The results so far show that the early-types in the GAMA regions can broadly be split into dusty, with some star formation still underway, and non-dusty. The dusty ones are “green valley” galaxies, as opposed to the “red and dead” ones on the red sequence. In contrast, galaxies in the Virgo cluster have less dust in them, but the galaxies here are closely packed together so galaxy environment could be important in how dust is generated or destroyed in a galaxy. There is still a lot of work to do with this topic, but it is an active topic and more results are on their way.

February Observing Evening

The forecast of clear skies for Tuesday 20th February had been consistent for about three days, but within an hour of announcing the observing evening at around 4pm it had completely clouded over.  Such are the frustrations of organising events in Kendal.

So it was an act of complete denial to go and set up at Boundary Bank, and I was delighted to see that I was not alone.  At about ten past seven, the security lights switched off, the clouds lifted and we had horizon-to-horizon clear dark skies.  The cold dry air brought a clarity and transparency rarely seen in Cumbria.

A relatively small turnout of about a dozen members, but with three good telescopes to share there was plenty of eyepiece time for everyone.  Special thanks go to David Glass for giving so much attention to the new members and making them feel very welcome.  One commented how delighted she was that people were willing to share the views through such amazing kit – I had never really thought of it in that way.

What did we see and do?  A round up of the constellations – with mythology from Moira – emphasising the difference between the rotating northern horizon and the ever-changing southern horizon, some double stars from David, star clusters including The Pleiades and the Perseus Double cluster, a long look at The Orion Nebula (below, my photo from 14 February) at various magnifications, a fruitless search for Uranus very close to the Moon.  

We finished with the Moon itself, an outrageously clear waxing crescent with fabulous detail around the terminator.  All in all, a very relaxed session with everyone just happy to be out.