4th January 2017
It´s the Welcome Back Social Evening once again.
It was a quiet affair this time around - plenty of folk to have a chat to, but not a patch on last year when we had four new people come along.
We are all looking forward with anticipation to another excellent year.
Next week we may have observing if we are very lucky, but typically the forecast is iffy it more likely to be Mike filling in with one of his excellent talks - Explorers of the Universe.
11th January 2017
Mike got started by asking Peter for any observing updates.
Peter said that Venus was stunning in the SW as soon as it´s dark and there was a comet to look at he´ll give us the details next week.
Mike had a number of flyers for the SPA Convention on 1st April. It is a must to have a ticket as they are not available on the day.
There were loads of Sky at Night mags and CDs for grabs.
It being too cloudy for observing Mike gave us the first part of his talk on:
Explorers of the Universe
Thomas Harriot 1560 - 2nd July 1621
Was an English astronomer, mathematician, ethnographer and translator. He is sometimes credited with the introduction of the potato to the British Isles. Harriot was the first person to make a drawing of the Moon through a telescope, on 26 July 1609, over four months before Galileo.
He worked for Sir Walter Rayleigh and later for Henry Percy.
He got his first telescope in 1609 - a Dutch Trunk - as they were known. He looked at the Moon and is credited with the first ever astronomical drawing, of the Moon. He also drew some sun spots and saw the moons of Jupiter.
He invented the mathematical sign ">" meaning more than and round the other way less than.
John Goodricke 17th September 1764 - 20th April 1786
Was an English amateur astronomer. He is best known for his observations of the variable star Algol (Beta Persei) in 1782.
He became deaf in early childhood due to a severe illness. His parents sent him to Thomas Braidwood´s Academy, a school for deaf pupils in Edinburgh and in 1778 to the Warrington Academy.
After leaving Warrington, Goodricke returned to live with his parents in York. There, he became friends with his neighbour Edward Pigott, whose father Nathaniel Pigott had built a sophisticated private observatory. Edward was already interested in variable stars, and he gave Goodricke a list of those that he thought were worthy of observation.
He observed Algol a variable star in Persius, noting it to have a period of 2.77 days. He was the first to explain that this phenomenon was due to it being a double star. He also found other variable stars such as Delta Cephei (5.4 days) and Beta Lyrae.
He was made a member of the Royal Society.
He achieved such a lot in his short life.
Vesto Slipher November 11, 1875 - November 8, 1969
Vesto Melvin Slipher was an American astronomer who performed the first measurements of radial velocities for galaxies, providing the empirical basis for the expansion of the Universe.
He worked under Percival Lowell and spent his entire career at Lowell Observatory in Flagstaff, Arizona, where he was promoted to assistant director in 1915, acting director from 1916, and finally director from 1926 until his retirement in 1952.
Slipher used spectroscopy to investigate the rotation periods of planets and the composition of planetary atmospheres. In 1912 he was the first to observe the shift of spectral lines of galaxies, making him the discoverer of galactic redshifts. In 1914 Slipher also made the first discovery of the rotation of spiral galaxies. He discovered the sodium layer around the Earth in 1929. This is used by modern day observatories who direct lasers onto it to measure distortions in the atmosphere caused by turbulence such that their adaptive optics can be adjusted. He was responsible for hiring Clyde Tombaugh and supervised the work that led to the discovery of Pluto in 1930.
Mike moved on to talk about:
Hot off the press this one - the Catalina Sky Survey yesterday reported a NEO that passed the Earth at half the Lunar Distance it was between 50 and 100 miles in diameter.
Next we saw an unusual image of the Earth and Moon in space - the Mars Reconnaissance Orbiter which is studying Mars took a break and looked at us briefly. Mike said the image of the Moon had to be enhanced as it was in the original a bit dim; it has a lower albedo than the Earth.
Dark Matter and Gamma Rays - It has been known for quite a while that we can only see a small percentage of the matter that makes up the Universe. A study was undertaken to try to explain this phenomena as to being in some way due to Gamma Rays. So far there are no conclusive results!
Lucy and Psyche
Lucy will launch in 2021 and will arrive at the L4 Trojan cloud (a group of asteroids that orbits about 60° ahead of Jupiter) in 2027, where it will fly by four Trojans 3548 Eurybates, 15094 Polymele, 11351 Leucus and 21900 Orus. After these flybys Lucy will return to the vicinity of the Earth whereupon it will receive a gravity assist to take it to the L5 Trojan cloud (which trails about 60° behind Jupiter), where it will to visit two more Trojans, the binary pair 617 Patroclus-Menoetius. Lucy will also fly by the Main Belt asteroid 52246 Donaldjohanson which is named for the discoverer of the Lucy hominine fossil.
Lucy will go on to visit Psyche an asteroid that is almost 1% of the mass of the whole asteroid belt - it is thought to be metallic.
Is very big and has been found to be spinning very quickly there is conjecture that it may have swallowed a companion star some time ago and that star´s energy would have been transferred to Betelgeuse.
Ice on Ceres
NASA´s Dawn spacecraft has been studying Ceres, the largest asteroid, and has discovered that at the poles in permanent shadow there may be ice.
Tabby´s Star or KIC 8462852 as it´s more formally known, made headlines last year when Tabetha Boyajian, then a postdoc at Yale University announced the discovery of this system´s strange patterns in brightness. The star´s weird dips have defied explanation and even prompted theories about extraterrestrial life.
The story keeps getting better: as astronomers called for more data and SETI searched for alien radio signals, archival investigations for historical context stirred up controversy on the star´s long-term trends. Now, with the release of a new study last week that finds that the star has long been fading, it looks like Tabby´s star is even weirder than we knew.
18th January 2017
Mike announced that Tim had to go on a business trip to Cologne and his talk on Dew Heaters has been postponed until 8th March.
Mike mentioned that the spring Astro Camp would be open to other astronomers. MikeB is organizing it at £12 per night so let him know if you intend to go.
Andrew said that he was already on the third version of our Programme!
Mike introduced Peter for his:
Update on Observing Highlights for January and February 2017
He recommended having a look at M45 the Pleiades Cluster. He advised where to find it with a finder chart of the Orion area. He said that this was the first object he remembers looking at with his small reflector balanced on a kitchen chair!
He said that Orion's belt stars could be used by following their line up to the right to get to Aldebaran in the Hyades and then on to M45.
We saw a very deep image showing M45 plus its surrounding nebulosity which is illuminated by the light from the cluster and is referred to as a reflection nebula. Peter explained that the current thinking is that the nebula is not part of the cluster it is just being passed through. M45 is 115 million years old and 444 light years away. He pointed out the California Nebula which is an Emission Nebula.
Peter explained that The Merope Nebula is a diffuse reflection nebula, possibly a supernova remnant, in the Pleiades star cluster, surrounding the 4th magnitude star Merope. Nearby is diffuse nebula IC 349, a reflection nebula called Barnard's Merope Nebula.
Peter said on 10/11th Feb. There would be a Penumbral Lunar eclipse from 22.30 until 03.00. It will be at its best at 00.45. Look for the colour change. He explained with a chart that the Moon passes through the outer part of the Earth´s shadow.
Peter said that Comet 45P Honda-Mrkos-Pajdusakova was already visible but not easily at present. We saw a lovely image of it - the tail is 20 long. He took the time to explain what a comet was - often with an orbit that took them way out into the far reaches of our solar system. It is low in SW in the evening but will become a morning object. With aid of a chart he explained where it was on a range of dates.
He said that Venus was terrific at -4.8 mag. with Mars to its left. Venus is visible in daylight if you know where to look. He stressed that you must stand in the shade of a building to avoid accidentally looking at the Sun.
In mid Feb at about 05.00 in the predawn sky Jupiter will be close to Spica and the Moon with Saturn low in the SE.
Mike introduced Andrew for his talk:
Splendid Stuff especially for new people.
25th January 2017
Peter said there was to be a BAA Deep Sky Meeting on 4th March. It will be an all-day event - he has spare seats in his car if you are interested - cost is £20 which includes food.
He added that Venus will be within 3° of the Moon on 31st.
Ted said he had secured the hall for another year the cost now was £16 per hour.
Mike reminded us that we should book a pitch through MikeB - cost £12 per night - for our next Astro Camp.
Mike introduced Andrew for his talk:
How the Sky Works Part 1
He began by asking Mike to set up his Sky software to show the sky at 22.00 - it showed Orion in the centre. He advanced the time to noon so we could appreciate the change then he advanced it 6 months. He then asked Mike to 'turn off the Sun'. It was amazingly the same as the earlier night sky with Orion in the centre.
Then he set the sky rotating and we could see that the point of rotation was Polaris. He said the Earth´s rotation causes everything to rise in the East and set in the West. He also explained that Polaris is at an angle that is equal to our latitude.
Circumpolar stars are stars that never set and showed us how the view of the sky changes dependant on the latitude.
Orion´s belt stars are roughly on the celestial equator which is 900 from the pole so 90 - 52 (our latitude) gives 380 which is the height of the celestial equator.
He explained Altitude and Azimuth - altitude (or ´alt´) and azimuth (or ´az´), are centred on the observer. Altitude is the angular distance of an object above the local horizon. It ranges from 00 at the horizon to 90° at the zenith.
He used Orion to by turning it so we could see it from the side and showed the stars in the relative positions and there are vast differences in distance from us.
He also said that what we call The Plough is actually an asterism of stars within the constellation of Ursa Major.
He moved on again to talk about the Signs of the Zodiac. As we learnt above the Sun moves through the background star field. Astrologers are of the view that the position of the sun at the time of a person's birth influences them. Andrew said he has a different view: - Astrology is a bit if fun uses the stars to tell someone's fortune. Whereas Astronomy is a lot of fun and causes someone to spend a fortune looking at the stars.
He explained that the basic problem is that the charts are based on where the sun was 2000 years ago. The Earth precesses and the wobble changes our position by 20 minutes per year. Therefore the zodiac signs are now one sign wrong. This happens every 2167 years!
Excellent science tempered with fun.