EAS Newsletter for July 2020

What’s in the sky this month

For Noctilucent Clouds (NLC), ISS passes, the Moon, the planets, comets, meteor showers and Sky Charts for this summer see our Sky Notes page.

Astronomy News July 2020 – David Glass, Richard Rae & Ian Bradley

Space X and Dragon launch

Dragon crew ship Endeavour docked with the ISS. This photo was taken on June 30th by NASA astronaut Col Doug Hurley whilst on a spacewalk. Credit: Twitter feed Col Doug Hurley@ Astro_Doug
Click the image for a full-page view

SpaceX made history with the launch of NASA astronauts aboard Spacex’s Dragon vehicle for a visit to the ISS.

The last weekend in May marked a turning point in frontier space history. A private company is now providing a “taxi service” to transport astronauts to the International Space Station. SpaceX has successfully delivered 2 astronauts. I hope you were all glued to the live NASA news feeds watching this significant event unfold. Sole dependence on the ageing Russian Soyuz capsules launching from Kazakhstan system is now a thing of the past.

To put this in perspective, the last astronaut to be launched from America was nearly a decade ago in 2011 with the space shuttle. Previously SpaceX has successfully sent un-manned flights to the space station in 2019 using automated docking procedures.

SpaceX transport system for crew and cargo will now be a gamechanger in this rapidly developing industry.

SpaceX (again)

Following on from the spectacular Crew Dragon launch and rendezvous with the ISS, our attention turns back to the Starship project. You’d think that they would have learned something from their high-profile failures – well it seems they might have. Starship SN5 has apparently passed a full cryogenic proof test on 30/6 and is now being fitted with a Raptor engine for further tests.

Earlier, a section of SN7 was tested to destruction. Whether this was intentional wasn’t known at the time. This a classic example of a quasi-instantaneous release of pressurised cryogenic liquid.

Keep an eye out for live coverage of engine testing and any other tests that happen. There are some lively amateur YouTube sites that provide running commentary from their own webcams on nearby apartment blocks trained on the testing site. Here is one with an informative running commentary, local insight and buzzing live chat.

Betelgeuse (Again)

You probably remember the dimming event that affected Betelgeuse last Winter. At the time, everyone thought that the star had coughed out a cloud of dust that caused it to dim at optical wavelengths. It turns out that it was probably giant “starspots” instead. A team used observations at sub-mm wavelengths to investigate what had happened. They found that Betelgeuse dimmed by around 20% at sub-mm wavelengths, which is much more than could be achieved by external dust. The dimming must therefore have been caused by large cooler patches in the star’s photosphere, possibly covering 50 – 70% of the star’s surface.

Here’s a link to the paper describing the results.

The “Missing Link” Between Neutron Stars and Black Holes

It’s been known for a while now that when massive stars end their lives as supernovae, they can leave behind either a neutron star or a black hole. However, no neutron star with mass greater than 2.5 times the mass of the Sun has been found, or no black hole with mass less than 5 Solar masses. There is a gap in mass which nobody understood. However, in August 2019 the LIGO gravitational wave observatory detected an object with a mass of 2.6 Solar masses, as it merged with a more massive black hole. No optical counterpart to the event was detected. here is the paper for this discovery (click on the pdf button).

They conclude “we cannot firmly exclude the possibility that [the less massive object] is a neutron star, nor can we be certain that it is a black hole”.

Pluto and its Sub-Surface Ocean

Montage of enhanced colour images of Pluto (bottom left) and Charon, from the New Horizons spacecraft. (NASA/JHUAPL/SwRI)

Montage of enhanced colour images of Pluto (bottom left) and Charon, from the New Horizons spacecraft. (NASA/JHUAPL/SwRI)
Click the image for a full-page view

The spectacular images of Pluto sent back by the New Horizons spacecraft were just the start. Based on the data received, there is now evidence of a liquid water ocean underneath Pluto’s crust. A team examined the images for signs of stretching or compression, which is what would happen if a sub-surface liquid ocean were to freeze because ice expands when it forms. However, nothing was found even in the oldest terrains, implying that sub-surface water is in a liquid state. This and other key findings are explained if Pluto formed hot within a few tens of thousands of years, and maintained its internal heat through collisions. Sub-surface oceans on planets (dwarf or otherwise) and moons are potential locations for extraterrestrial life, and therefore attract a lot of interest. The paper is behind a paywall , but the abstract is worth a read.

 

Remote Observing with the IRAM 30m Telescope – from Windermere

After poor weather during my last trip to the IRAM 30m telescope in Spain, I was given more time to observe. However, because of Covid-19 travel restrictions, I had to do this remotely from Windermere…

This worked very well, and I managed to get everything observed for my project during the last week of June. I also invited another postgrad student to join in remotely from Preston, to get the experience of observing with this telescope. I’m very grateful to the folk at IRAM, Granada for getting the telescope operational again after the Covid-19 crisis.

Centaurs – Richard Rae

I am sure we were all intrigued to hear about extra-solar system visitors to our solar system such as the interstellar object Oumuamua that was discovered floating through our patch of space in 2017. However, would it not be quite the discovery to find we have had “visitors” from afar joining our solar system many millions of years ago!

Centaurs are small intriguing objects that have orbits that cross those of the outer planets.

New research examining the past orbits of these Centaur objects focuses on their origin and whether or not they could have been present at the formation period of our solar system. The paper by Fathi Namouni (Observatoire de la Côte d’Azur, France) and Maria Helena Morais (Universidade Estadual Paulista, Brazil) suggest that 19 obects have been captured by our solar system that were previously orbiting other stellar systems.

Who would have believed we had so many interstellar objects within our midst?

For the full MNRAS paper click this link.

Neutrinos from the Sun confirm stellar physics theory – Ian Bradley

For many years, the lack of the expected neutrinos from the Sun puzzled astrophysicists. In the 1960’s, Ray Davis’ huge tank of cleaning fluid detected far fewer neutrinos than expected.

The Borexino experiment, Gran Sasso, Italy. A researcher stands in a spherical vessel that 278 tonnes of liquid hydrocarbons Credit: Volker Steger/SPL

The Borexino experiment, Gran Sasso, Italy. A researcher stands in a spherical vessel that 278 tonnes of liquid hydrocarbons Credit: Volker Steger/SPL

Neutrinos are released by fusion reactions inside the core of stars and provide a direct way to measure those processes. They are extremely difficult to detect despite thousands of millions passing through your fingernail each bsecond. The rate of neutrinos detected from the Sun, indicates the rate of fusion inside the core of the Sun. Davis’s experiment only measured 30% of the expected rate. That problem was solved when it was discovered in the early 2000’s that neutrinos can change in their passage from the Sun to detectors on Earth into ones the detectors couldn’t detect. Detectors have improved enormously, both in efficiency and size, since Ray Davis’s day.

nside the core of the Sun, the main fusion process is 4 protons fuse together (in a multistage process) to produce helium and energy [plus two neutrinos]. This proton-proton chain reaction dominates in low mass stars like our Sun. In higher mass stars, a different process dominates – the carbon-nitrogen (CN or CNO) reaction. The nett result is the same, 4 hydrogen nuclei fuse together releasing helium, energy and two neutrinos. In stars like our Sun, the core is too cool for this process to be dominant and only about 1% of the Sun’s energy is produced by this process.

However, the new detectors have allowed this weak process to be detected despite the high background from p-p chain neutrinos. This detection confirms for the first time the decades- old theoretical predictions that some of the Sun’s energy is made by this process and that our understanding of the fundamental fusion processes is correct. More details in this full article [free].

A simple project: a right-angle polarscope viewer – by David Glass

Some of us at least have had the joy of trying to use a polarscope to align a telescope at our latitude. I don’t know anyone with a sufficiently flexible neck or back to do it properly. The solution – make a right-angle viewer. A good recipe is here.

…and I thought I’d give it a go.

I managed to get an old Pentacon (East German) right-angle camera finder on Ebay – it was grubby but it cleaned up very well. I then cut up an old 35mm film canister and made a shaped slot at the back to fit the adapter – and voilà! No more wet/dented knees and sore neck. The viewer is not that heavy and doesn’t affect the polarscope. The film canister provides a snug fit and can be removed without harming the polarscope.

Making a right angle viewfinder for a Skywatcher Star Adventurer camera tracker (Image Credit: David Glass)

Making a right angle viewfinder for a Skywatcher Star Adventurer camera tracker Image Credit: David Glass

Recent Photographs

The Eagle Nebula, M16 and the Pillars of Creation. A real challenge as always less than 20 degrees maximum altitude from my backyard and directly over central Kendal on 31st May.

The Eagle Nebula, M16 and the Pillars of Creation. A real challenge as always less than 20 degrees maximum altitude from my backyard and directly over central Kendal on 31st May.
Click the image for a full-page view.

This shows just how short the night is at the end of May. The sky brightness was measured using data from the same imaging run used for the picture of M16. The detected brightness in a region with no stars was measured. Pre-dawn is seen by the rapid brightening around 0230. Only date from within the blue region was used to create the M16 image.

This shows just how short the night is at the end of May. The sky brightness was measured using data from the same imaging run used for the picture of M16. The detected brightness in a region with no stars was measured. Pre-dawn is seen by the rapid brightening around 0230. Only date from within the blue region was used to create the M16 image.

The Crescent Nebula in Cygnus powered by a Wolf-Rayet star. Imaged from Kendal.

The Crescent Nebula in Cygnus powered by a Wolf-Rayet star. Imaged from Kendal.
Click the image for a full-page view

M61 in Virgo with supernova SN2020jfo indicated on May13th. This supernova was first detected May 6 2020, so a week earlier. Imaged from Kendal.

M61 in Virgo with supernova SN2020jfo indicated on May13th. This supernova was first detected May 6 2020, so a weekearlier. Imaged
Click the image for a full-page viewfrom Kendal.

Globular cluster M13 in Hercules. Imaged from Kendal

Globular cluster M13 in Hercules. Imaged from Kendal.
Click the image for a full-page view

M5 in Serpens. Imaged from Kendal.

M5 in Serpens. Imaged from Kendal.
Click the image for a full-page view

M10 in Ophiuchus. Imaged from Kendal

M10 in Ophiuchus. Imaged from Kendal.
Click the image for a full-page view

M12 in Ophiucus. Imaged from Kendal.

M12 in Ophiucus. Imaged from Kendal.
Click the image for a full-page view

EAS Newsletter for June 2020

What’s in the sky this month

For Noctilucent Clouds (NLC), ISS passes, the Moon, the planets, comets, meteor showers and Sky Charts for this summer see our Sky Notes page.

Astronomy News – Richard Rae

SpaceX makes history with NASA astronaut launch

This last weekend in May marks a turning point in frontier space history. A private company is now providing a “taxi service” to transport astronauts to the International Space Station. SpaceX has successfully delivered 2 astronauts to the International space station. I hope you were all glued to the live NASA news feeds over the weekend watching this significant event unfold. Sole dependence on the ageing Russian Soyuz capsules launching from Kazakhstan system is now a thing of the past

Here is what Stuart Atkinson had to say 

The launch of the first crewed (and it is “crewed”, not “manned”; NASA stopped using that term years ago) SpaceX Dragon capsule to the International Space Station last weekend was both a technological triumph and a fascinating combination of amazing technology and Hollywood hype. Although it will never take the place in my heart left by the sleek Space Shuttle orbiters, with its shiny white hull, its glowing blue, swinging touchscreens and its roomy cabin the Dragon capsule is a thing of beauty, and comparing it to the Soyuz capsules US astronauts have been flying in since Shuttle was retired is like comparing a Formula 1 Ferrari to Del Boy’s ride. Although it might look like a pimped-up version of the old Apollo capsules – and comes back to Earth in the same way, splashing down in the ocean beneath a trio of red and white parachutes – it is much more than that. Make no mistake, the Crew Dragon is a proper spacecraft. The future is here, and it doesn’t have wings.

It was a shame the launch was delayed a few days because of the weather. Not just because it meant all the exciting build-up of the original launch day was wasted – they very generously showed us everything, hours of uninterrupted coverage, from the two astronauts suiting up to the aftermath of the launch cancellation – but because I was at work when the Falcon 9 eventually did leap into the sky, and could only watch snippets of the coverage during my break. But when the Falcon did eventually fly if you listened very, very carefully you could just hear, above the roar of its engines and behind the whoops and cheers and chants of “USA! USA! USA!”, NASA’s bosses letting out a deep sigh of relief. Not just because the risky decision to pay a private company, run by a brilliant but egotistical billionaire, to design, build and launch a crewed spacecraft had paid off, but also because it meant the days of having to cadge lifts up to the ISS from the Russians were finally over. As they mentioned just a few times during the NASA TV coverage America had entered a new age, a new golden age of American astronauts flying an American spacecraft! From American soil! Yeah!

So is this a big deal? Really? Well, yes, it is, although it’s not the spaceflight revolution some are claiming. Crew Dragon isn’t the first reusable spacecraft – hello? Space Shuttle? – but it is a great piece of kit, and will hopefully give the US crewed space program a much-needed kick up the water-cooled backside and allow NASA to let SpaceX (and Boeing, if they get their act together and stop their Starliner capsule’s computers from having HAL-like breakdowns) take care of ferrying people to and from the ISS and start to plan seriously how to send expeditions to the Moon and Mars.

This was a real triumph for SpaceX, no doubt about that. Elon Musk isn’t God, despite what some of his army of worshippers think. He’s not Tony Stark either. But he doesn’t just talk the talk, he walks the walk, and every ambitious goal he sets himself and SpaceX he reaches, eventually, even if his timetables can be unrealistic and his Starship rockets have a habit of blowing up. His thousands of night sky-ruining Starlink satellites might be an abomination, but with Crew Dragon he might just have taken the shackles off NASA’s wrists and given it a chance to explore again.

I hope so.

History

The last astronaut to be launched from America was nearly a decade ago in 2011 with the space shuttle. Previously SpaceX has successfully sent un-manned flights to the space station in 2019 using automated docking procedures.

SpaceX transport system for crew and cargo will now be a gamechanger in this rapidly developing industry.

NASA Space-X Launch transports 2 astronauts to the ISS. Saturday 30th May 2020


NASA Space-X Launch transports 2 astronauts to the ISS. Saturday 30th May 2020

The Dragon spacecraft is capable of carrying 7 passengers into space. Source: (https://www.spacex.com/vehicles/dragon/)


The Dragon spacecraft is capable of carrying 7 passengers into space. Source:
(https://www.spacex.com/vehicles/dragon/)

A unique feature of the Space X Falcon 9 Engine is its ability to land and be used again after delivering its payload into orbit.


A unique feature of the Space X Falcon 9 Engine is its ability to land and be used again after delivering its payload
into orbit.

This video capturing the Saturday landing of the Falcon 9 rocket on a ship in the ocean is well worth reviewing.

The "zero-G indicator" is deployed by a crew member with the Dragon module shortly after second-stage engine shutdown!

The “zero-G indicator” was deployed within the module shortly after second-stage engine shutdown!

Ups and downs of the SpaceX Industry

And just a day before the launch, SpaceX struck disaster at the test facility in Texas. On Friday a SpaceX prototype engine exploded after a couple of minutes of testing. This project is developing propulsion systems for the heavy lift Starship rocket to be used in future piloted and cargo flights to the Moon and beyond.

The Starships prototype engine being tested. The raptor engine is lying horizontally during testing.

The Starships prototype engine being tested. The raptor engine is lying horizontally during testing.

No reported injuries as a fireball engulfs the test site in Boca Chica Texas.

No reported injuries as a fireball engulfs the test site in Boca Chica Texas.

Artemis

ESA – The European Space Agency in signing this contract last week with Airbus to build the third European Service Module (ESM) drives forward the Artemis III project that will be used to transport astronauts to the Moon. A large project involving a collaboration of commercial and international partners.

Exciting developments in the Artmis mission can be followed here.

 

James Webb Telescope Fully Stowed

The James Webb Space Telescopes is said to re-write textbooks after it launches next year (NASA)

The James Webb Space Telescopes is said to re-write textbooks after it launches next year (NASA)

News recently from the James Webb Space Telescopes reports the largest and most complex space science telescope ever built has been successfully folded to the position it must be in when it is inserted into an Ariane 5 rocket. The project has been plagued by delays is set to launch next year.

This most interesting 10-minute video explaining how this huge space telescope will be deployed after its launch next year.

ESPRESSO confirms “Earth-sized” planet orbiting our closest star Proxima b

This is an artists impression of an Earth sized planet orbiting our closest star Proxima b which is around four light years from the sun.

This is an artists impression of an Earth sized planet orbiting our closest star Proxima b which is around four light years from the sun.

The Earth sized planet (1.17 times the mass of the Earth) that orbits our closest star has been CONFIRMED by the unprecedented precision of a Swiss made spectrograph.

The Swiss instrument termed ESPRESSO is installed on the VLT (Very Large Telescope) that operates in Chile. Although the HARPS instrument, an older type spectrograph detected the planet 4 years ago the newer instrument improves upon the previous measurements by a factor of three.

Although the orbit is much closer than the Earth is to the Sun, Proxima b is much cooler. This means being closer to a cooler object the radiation received is comparable to the energy received here on Earth. It is thought liquid water could exist here and the planet would be a candidate for future biomarker research.

And finally, we end on a Supernova …

The first detection was on May 6th 2020 and AT2020jfo is described as a young , rising supernova in the nearby spiral galaxy M61.

Many thanks to Ian Bradley EAS for sending the attached photograph of Supernova 2020jfo.

Many thanks to Ian Bradley EAS for sending the attached photograph of Supernova 2020jfo.

Ian comments – “Supernova 2020jfo In M61, only the second one I’ve ever captured, a supernova indicated by the yellow lines – SN2020jfo – captured May 13 2020. “

Further information on this recent outburst.

EAS Newsletter for May 2020

What’s in the sky this month

For Noctilucent Clouds (NLC), ISS passes, the Moon, the planets, comets, meteor showers and Sky Charts for this summer see our Sky Notes page.

Astronomy News – David Glass

SpaceX

Very recently, SpaceX announced that they are to test a “VisorSat” when they next launch a batch of Starlink satellites. The aim is to reduce their reflection to the point where astronomers can cope with their presence. They should work better than the “DarkSat” they launched as a test a while ago. They won’t remove all streaking on images, though.

Whether this is enough to preserve the night skies and allow quality images for both amateur and professional astronomers remains to be seen.

SpaceX’s prototype Starship

SpaceX’s Starship has just managed to pass a cryogenic proof test without bursting, after another dramatic failure early in April. The next stages are to test-fire the associated Raptor rocket, which may happen very soon, and then try a “Hop”. See film footage of the proof test.

The Mk1 Starship 2nd stage module. It is fully reusable, 9m in diameter and 50m high. This will be launched on the top of a SpaceX’s super- heavy lifter, itself 68m high. The combined rocket will be slightly taller than the Apollo Saturn 5’s 111m.

Here is some footage of an earlier test which was not quite as successful but more dramatic…they have learned a lot since then.

Watch out for press conferences about their launch of Crew Dragon, carrying personnel to the ISS – the first crewed launch from the US for quite a while! SpaceX and NASA are targeting May 27th. NASA Administrator Jim Bridenstine says he is “fairly confident that this launch will be at the end of May, beginning of June.

Fomalhaut b Disappears

Back in 2008, astronomers managed to get the first optical image ever of a A jupiter-sized exoplanet orbiting Fomalhaut, named Fomalhaut b. Unfortunately, new observations using HST show that it wasn’t an exoplanet, and was probably the highly reflective remnants of a collision between two icy bodies. NASA have released a movie to show what happened to the object:

Our own Solar system has lots of icy dwarf planets in its outer reaches, but none have been observed in a collision yet. Catching such a collision in another stellar system is quite an achievement, even if it isn’t a proper exoplanet!

Hubble Space Telescope

he Hubble Space Telescope (HST) reached its 30th year of operation on 24/4/20, and will continue to do amazing work until at least 2025. To celebrate this milestone, NASA, ESA and STSci released a stunning image of a star forming region in the Large Magellanic Cloud (LMC), with NGC2014 on the right and NGC2020 on the left. The region is known as the “Cosmic Reef”. The blue colour is emitted by oxygen atoms and the red by hydrogen and nitrogen atoms, which are very hot or are blasted by ultraviolet radiation from giant newly-formed stars. NGC2020 is associated with a massive Wolf- Rayet star (think back to Joanne Pledger’s talk in February), and is an outer layer of the star that has been ejected.

Go to the website to see the image in all its stunning glory.

C/2019 Y4 (ATLAS)

As mentioned earlier, at the end of April HST was used to capture the disintegrating comet C/2019 Y4 (ATLAS). The outflow of gases from the comet as it approached the Sun might have led to its breakup into about 30 fragments. So, what might have become a comet visible to the naked eye sadly won’t.

Comet /2019 Y4 (ATLAS) as imaged by HST on two days documenting the breakup. In addition, see a good discussion

The Great Debate

It’s 100 years since a major debate took place to decide whether the Milky Way was the entirety of the Universe and all nebulae existed within it, or whether nebulae were other “island universes” outside of the Milky Way. We take the latter as fact today, but only 100 years ago it was still a hot topic with a lot at stake for the champions of both views. For a lively account of what happened and who was involved, go to: https://astronomy.com/news/2020/04/the-great-debate-of-shapley-and-curtis–100-years-later

Access to Astronomy Papers

The astronomy and astrophysics community is fortunate in having access to loads of free academic publications. Many fields of science have their papers behind paywalls, so it’s difficult for people outside of institutions to do research. Two of the most important ones for us are given below.

The Astrophysics Data System (ADS) is a database of published papers going back centuries and is right up to date.

To use it, try clicking on First Author and entering a name in the field that appears (e.g. Hubble). Then click on date and enter 1926-1930 in the field that appears. Then click on the magnifying glass, and you’ll get a list of papers that fit the criteria. Click on a paper, and you’ll get the details (with an abstract if one exists), and on the right you can access the actual paper (subject to certain paywalls!) using the small icons e.g. Publisher, pdf symbol. Try the 1929 paper (no. 6 in the list) – you’ll see the first evidence that the Universe is expanding! You could also try seeing just how far the database goes back – try searching on Herschel 1770 – 1790 and see if you can find a paper entitled “Account of a Comet”. What had he actually discovered? You can also search on specific keywords e.g. pulsar, supernova, M31.

Another highly valuable resource is ArXiv This is where people put their papers that are on the verge of publication, free of paywalls. While it is cutting-edge and free, the papers aren’t necessarily peer-reviewed and a few may not stand up to scrutiny. Some April 1st postings are brilliant (e.g. explaining the severe and long Winters in Westeros!). You can search on specific authors or topics of interest to see the latest papers on a topic. You will see an Astrophysics category link lower down the page, to make the search more specific.

A simple project – star trails

This is possibly the simplest astrophotography thing you can try bar a single shot. I haven’t done this for many years until a few days ago, so it was all guesswork. I was very pleased with the result.

  • A reasonable digital camera, DSLR or mirrorless
  • A fairly wide-angle lens. The typical kit lens that most DSLR cameras come with would suffice – these are usually 18-55mm or similar at its widest [smallest number]
  • A tripod
  • A remote release of some form – maybe the camera software or it might even be possible with a modern camera to use a mobile app. [I haven’t tried this .] I just use a simple switch that plugs into the 2.5mm socket in the side of my Canon DSLR
  • A fully charged battery and a memory card with sufficient space
  • A reasonably dark site – better without a strong Moon
  • An interesting foreground makes a better picture e.g. a church tower, an interesting building, a tree…

Turn off the autofocus and image stabilisation. Set the camera to manual and open up the lens to its biggest aperture – smallest f-number. Set exposure to 30 seconds and a reasonable iso – not too low or too few stars will be visible, equally not too high or it becomes cluttered. Some experimenting is required to get these right. There is no right – just does it look good! If 30 seconds exposure isn’t enough for your lens, try longer although without an intervaometer, that could be rather tedious.

The hardest bit is getting a reasonable focus. Autofocus will not work. Looking at a realtime image, Liveview, on the back screen helps a lot. Initially manully focus on a distant object and then find a bright star. Zoom right in [on the Liveview screen and not the lens zoom!] on the star [or even the Moon or Venus] and manually adjust the focus until the star is as small as possible. If your camera doesn’t have the Liveview facility, just take a shot, look at it zoomed in, and repeat. That is just a bit slower and more fiddly.

Take lots of sequential photographs for about an hour or so. To get the trails image, simply use the free startrails software available from , add the jpeg images [RAW files are not required which saves space on the memory card] and ‘press’ the button. It even sorts out the foreground for you an can give you a timelapse video if you want one.

The picture above was taken on my Canon EOS 750D with a Tokina 11-16mm wide angle lens, set to 11mm and f2.8. 76 exposures of 30 seconds each at ISO800. I set the camera to repeatedly take pictures, this symbol on my Canon and triggered the shutter. It continues to take images until I released the trigger – hence the switch. I was laid on the side of the River Kent, 50m or so from my house, with a bottle of beer in one hand, being buzzed by hunting bats whilst I stared at the sky… many satellites and one solitary late Lyriad meteor. A few minutes later at home, I had that picture.

Go on, have a go.

Recent Photographs

M97 the Owl Nebula and M108. Imaged from Kendal

M97 the Owl Nebula and M108. Imaged from Kendal

M51, the Whirlpool Galaxy. Imaged from Kendal

M51, the Whirlpool Galaxy. Imaged from Kendal

M94 in Canes Venatici. Imaged from Kendal

M94 in Canes Venatici. Imaged from Kendal

 
M63 The Sunflower Galaxy. Imaged from Kendal.

M63 The Sunflower Galaxy. Imaged from Kendal.

 M104 The Sombrero Galaxy A bit of a challenge as only 20° above the horizon and directly over central Kendal. M63 The Sunflower Galaxy. Imaged from Kendal

M104 The Sombrero Galaxy
A bit of a challenge as only 20° above the horizon and directly over central Kendal.

NGC4565, the Needle Galaxy in Coma Berenices. Imaged from Kendal.

NGC4565, the Needle Galaxy in Coma Berenices. Imaged from Kendal.

EAS Newsletter for April 2020

What’s in the sky this month

For the moon, planets, Comet C/2019 Y4 (Atlas) and deep-sky objects, see Ian Bradley’s notes, links and illustrations on our Sky Notes page.

Astronomy News – David Glass

A quick round-up of just a few fascinating things that have been publicised during March and early April!

Betelgeuse

Our neighbourhood red supergiant star Betelgeuse has caused quite a stir recently, thanks to a relatively rapid dimming event monitored by (amongst others) the Association of Amateur Variable Star Observers (AAVSO). Is it building up to go supernova? Probably not. At our March meeting, we saw evidence that it is brightening up again. Pop outside when the sun has gone down, and (cloud permitting) you can see for yourself that Orion is looking as it should again.


Thiscomparison image shows the star Betelgeuse before and after its unprecedented dimming. The observations, taken
withthe SPHERE instrument on ESO’s Very Large Telescope in January and December 2019, show how much the star has faded
andhow its apparent shape has changed.

So, what happened? In March we thought that a large puff of dust in our direction had caused the dimming, but the evidence was still a bit sketchy. The apparent shape change is indicative of that. However, new research published in March showed that the “surface temperature” of Betelgeuse was only slightly cooler as a result of the dimming. The surface of a star is not something we could stand on but is where electromagnetic radiation from the body of a star can escape unhindered (and do useful things like warm planets and get measured by astronomers). So, the dimming wasn’t due to Betelgeuse cooling off, and it was business as usual except for something in the way of our line of sight.

An exercise:

  1. Go to the AAVSO website
  2. hover the mouse over data
  3. data access and click on Light Curve Generator v2
  4. type in Betelgeuse as the star name. use the “Select Bands” radio button and tick the box below the green square for V band (you can pick others as well if you wish, like the black circle for plentiful visual estimates)
  5. click on “Julian Day”, and select “Calendar Date” from the drop-down menu
  6. You can adjust the dates plotted. When you’re done, click “Send” – and admire the result!

SpaceX Starship SN3

Hot on the heels of SpaceX Starship SN1 launch and second stage separation (unintentional!), Starship SN3 was put in position for testing. For some great footage of this happening

A live webcam is also available.

Live Webcams

There are some fascinating astronomy-webcams to explore if you’re stuck at home. Here are three to be going on with:

Satellite and Telescope Models to make at home

If you’ve got access to a printer, it’s easy to get the designs to make some impressive 3D models of your favourite satellites or spacecraft and some ground-based telescopes. Here are some of the designs out there:

There are quite a few others out there – if you go to the home page of a satellite (in Earth orbit) or spacecraft (away from Earth Orbit) and look in the outreach sections, you should find something to build. Send us the photos of what you built!

Astronomy Podcasts – Clive Rowland

You may be interested in listening to podcasts on astronomy – here are a couple

Recent Photographs – Ian Bradley


Venus on 20th March. From a video taken with a Meade LX200R a, x2 Barlow and a Philips SPC900NC webcam


M51, the Whirlpool Galaxy. Imaged from Kendal

101 The Pinwheel Galaxy. Imaged from Kendal


M101 The Pinwheel Galaxy. Imaged from Kendal

M97 the Owl Nebula. Imaged from Kendal


M97 the Owl Nebula. Imaged from Kendal

M81 & M82 in Ursa Major. Imaged from Kendal


M81 & M82 in Ursa Major. Imaged from Kendal

 

Notes and links from the March 2020 meeting

Welcome and Notices Ian Bradley EAS

The society has been notified of two reflector telescopes for sale, one a 5″ Sky-Watcher with an equatorial drive for £60 the other a Meade on substantial Equatorial tripod for £300. Use the main menu EAS About Us/Contact page for details.

Astronomy News David Glass EAS

Betelgeuse

News this month started off with the latest on Betelgeuse, which is now starting to brighten according to photometry from the Association of Amateur Variable Star Observers (AAVSO). A substantial emission of dust could be responsible, based on the latest images from ESO’s Very Large Telescope (VLT). One very high-resolution image shows that Betelgeuse has changed in shape and has a darker patch compared to a year ago. Another shows a substantial dust cloud around the star emitting in infra-red. We’ll keep an eye on the situation in case anything else happens!

Betelgeuse light Curve to beginning of March

Betelgeuse light Curve to the beginning of March

Launching Satellite Clusters

Next, SpaceX and their Starlink satellite clusters. The Russian Academy of Sciences is taking the issue of their impact on astronomy to the United Nations. A report from the European Southern Observatory (ESO), examining the impact of many small satellites on ground-based optical astronomy, found a limited impact on deep imaging of very small areas of sky (apart from cost) and on the visual appearance of the night sky. However, the impact on wide-field surveys is likely to be significant. They have not yet addressed radio astronomy, which will be covered in another report.

SpaceX Starship SN01 Test

The testing of the cryogenic liquid tanks for the SpaceX Starship SN01. During a cryogenic proof test using liquid nitrogen (a safer option than fuel or oxidant!), the lower liquid oxygen tank split causing the whole assembly to lift. On crash-landing, the upper liquid methane tank was propelled away. We await definitive information on the causes of this failure, but the fault could be related to welds joining the stainless steel bands and plates that form the tanks. When in service, the Starship (plus first stage) should be capable of sending payloads of over 100 tonnes (equivalent to over 3 fully-laden 40-foot containers) into low-Earth orbit. It is also intended for travel to the Moon and beyond

Earth has a New Moon

The Earth has a new moon (for now!). 2020 CD3 is about the size of a small car (not a Tesla!) and has a 47-day elliptical orbit. It is likely to leave orbit soon.

Listening to meteors

David brought to our attention a streaming service submitted by our amateur radio member, Clive Rowland: the Meteor Echoes project is now live and streaming on: meteors entering the atmosphere.

What’s in the Sky for March 2020 Ian Bradley EAS

For Constellations, Binocular objects, Deep Sky objects ISS passes visible this March see our What’s in the Sky this month by Ian.

Hide and Seek with Wolf Rayet Stars Dr Joanne Pledger Guest Speaker

Dr Pledger quickly introduced us to Wolf Rayet Stars (WR stars): massive, highly evolved and bright stars. Over 8 solar masses, over 1,000 times brighter than our sun, and extremely hot at 30,000K, compared to the sun at 6,000K, their effect on their physical environments can be extreme and lead to a number of theoretical anomalies and outstanding questions.

Image of WR 124 and the nebula M1-67 in Sagittarius. Captured by the NASA/ESA Hubble Space Telescope.

WR 124 and the nebula M1-67 in Sagittarius. Captured by the NASA/ESA Hubble Space Telescope.

First categorized in the mid-19C by the unusual broad emission-lines in their spectra that lack the element hydrogen (the fuel of most stars during their evolution). While many types of stars have mass enough to progress to the second element, helium, after burning all their hydrogen, WR stars feature not only helium but nitrogen, carbon, silicon, and even oxygen in their spectra.

Wolf–Rayet stars turn out to be a normal stage in the evolution of very massive stars. Initial categorization was into two types, WN and WC, depending on whether the spectrum was dominated by lines of nitrogen or carbon-oxygen respectively. Some show traces of hydrogen in their spectrum suspected of being either older Wolf–Rayet stars (WNL stars) with dust envelopes (WN stars) or, on the other hand, young massive stars evolving through a short life cycle.

WR stars, with their high mass, are mooted as possible progenitors of supernovae, particularly the newly-discovered types Ib (lacking hydrogen) and 1c (lacking hydrogen and helium) supernovae. Nonetheless, no conclusive identification has yet been made of such a progenitor.

Before the final supernova explosion, high mass stars can survive the Red Supergiant stage, expelling their outer layers in a nova event, to retract and progress on to become WR stars – burning through the elements heavier than hydrogen and helium. The ejected high-temperature elements and interstellar dust may be energized by high radiation and stellar winds from the WR star to become a Wolf–Rayet nebula.

WR 31a with a Wolf–Rayet nebula Credit:by the NASA/ESA Hubble Space Telescope.

WR 31a with a Wolf–Rayet nebula Credit: NASA/ESA Hubble Space Telescope.

Notes and links from the February 2020 meeting

Welcome and Notices David Glass EAS

Neighbouring events

David Glass welcomed everyone to the meeting and described the Moonwatch that took place on 1st Feb, Brewery Arts Centre. David, Graham Fell and Ian Bradley attended. In spite of poor forecasts, the half-moon put in an appearance for about an hour and several people looked through David’s 20cm SCT (28mm eyepiece with Lunar filter) at the terminator – and were all seriously impressed. Next one is the 29th of this month.

David also publicised the Dark Skies Festival run by the Friends of the Lake District and encouraged people to get involved. FoLD is leading a campaign to get the Lake District accredited as a Dark Skies Reserve, which deserves our support. David also gave a quick summary of his observing visit to the IRAM 30m telescope, Spain – a warm welcome there as ever.

Sky Notes for February 2020 Phil Morris EAS

For the Moon phenomena, February planets, the winter constellation, Orion, and more see our Sky notes for this month. for this month by Phil:

Astronomy News for January 2020 part 1 David Glass EAS

Betelgeuse

One item which hit the headlines recently is Betelgeuse – it has dimmed significantly over the last few weeks, and there is speculation that it is about to go supernova. On 6th January this year, AAVSO put out a bulletin urging their observers to get photometric and spectroscopic observations urgently. Looking at the light curve from AAVSO over the last 10 years, Betelgeuse has definitely dimmed and is less than 30% as bright as it was early in 2019. Whether this indicates that it is about to blow is not certain though. Another explanation is that it has puffed out stellar winds in our direction that are laden with dust (this type of star is known to do that). Watch this space!

Betelgeuse and Minimum graph

Betelgeuse and Minimum graph

Launching Satellite Clusters

Another significant item is the recent launch of a cluster of 60 250kg satellites, as part of an eventual network of thousands to provide broadband across the planet. Early examples are already affecting astrophotography and are visible to the naked eye. The longer-term effect on ground-based astronomy and astrophotography is not looking good at the moment. On 8th of this month, the American Astronomical Society (AAS) held a meeting to discuss the scheme and its implications, and it is understood that the Royal Astronomical Society (RAS) has put together a working group with a similar aim. Whether this is in time to mitigate the worst impacts remains to be seen.

The Transiting Exoplanet Survey Satellite (TESS)

On a brighter note, the TESS satellite has discovered a rocky planet (TOI 700d) around an M-class dwarf star about 100 ly distant, which orbits within the star’s habitable zone. This star was mistaken for a The sun-like star initially, but a team including a high-school student, have put this right. The star appears to suffer fewer violent flares than other similar stars, so the prospects for conditions favourable to life on this planet are greater.

Alston observatory workshop and lectures

Closer to home, UCLAN is running free astrophotography workshops at their Alston observatory. The official closing date for applications is 16th January. See details.

Also, UCLAN is holding their next public astronomy lecture on Friday 24th January. Details to follow.

Astronomy News for January 2020 part 2 Richard Rae EAS

Richard Rae gave a report from Astrofest 2020 that was held in London. There were many new exciting missions to report, including the comet intercept and Asteroid deflection projects. Jan Worner the head of the European Space Agency came to give a talk on ESA and all the missions and partnerships in which it is involved. He ended by commenting ESA will not go back to the Moon but it must be seen as going forward to the Moon.

Astrofest poster

Things to Come Stuart Atkinson EAS

Stuart gave a very informative talk entitled “Things to come”

The talk focused on the companies and partnerships that would take humans into space and highlighted the possibility of space tourism in the not too distant future.

Virgin Galactic may be one option for tourists to gain access to space albeit for about three minutes!

EAS meeting and Virgin Galactic impression

Blue Origin is a rival to Virgin Galactic and may offer longer and cheaper trips into sub-orbital space

Boeing`s Starliner project is a serious attempt at providing a route for a crew to travel to the ISS. Although this project has had some recent setbacks.

The main contender to Boeing`s Starliner is Elon Musk`s Crew Dragon. This is ahead of development and has recently successfully tested its escape pod mechanism.

Crew Dragon’s first crewed test flight to the ISS is due in March 2020.

Crew Dragon’s badge

The SpaceX Starship proposed project is huge! It will be able to put 100 people into space and travel to the Moon and Mars.

SpaceX Starship project

Other projects briefly covered were:-

Artemis 2028 impression

Stuart ended by saying that Elon Musk considers by the end his life he will be living on Mars.

Notes and links from the January 2020 meeting

Welcome and Notices Ian Bradley EAS

Neighbouring event

As part of Cumbria Dark Skies Festival 2020, Cockermouth Astronomical Society will be holding two events on Saturday 22nd February 2020:

  1. from 1- 4pm in Keswick’s iconic Moot Hall “An afternoon of talks by some of the UK’s top astrophotographers” Speakers:
    • Jeremy Hunt – Astrophotographer and author of “Astrophotography and the lifecycle of stars”
    • Stephen Cheatley – Blackpool based professional photographer with beautiful images of the night sky and famous UK landmarks
    • Pete Williamson – FRAS, broadcaster, astronomer and consultant on the Faulkes Telescope Educational Project
    Booking: contact Jeremy Hunt (07535540499) or via the Cockermouth Astronomy Society Facebook page Capacity 45 – so there may not be seats available on the day £5 per talk; or £10 for the entire session.
  2. from 6:30pm a Public stargazing session that evening 18:30 – 21:30 in Crow’s Park, Keswick – free See our Neighbouring Events page

Observing Session

Weather permitting we hope to hold an Observing Session Thursday 16th January.

Sky Notes for January 2020 Ian Bradley EAS

This January will be a good time to follow the comet Comet/2017 T2 (Panstarrs) with binoculars moving through the Milky Way between the constellations of Perseus and Cassiopia

On January 27th at sunset, Venus and Neptune very close together. Venus – the unmissable bright ‘star’ in the South West at 6pm. Neptune is magnitude 7.9 – so you will need binoculars at least.

Moon compared to Venus and Neptune




The Moon compared to Venus and Neptune

For Orion and more on our EAS Sky notes for this month.

Astronomy News for January 2020 David Glass EAS

Betelgeuse

One item which hit the headlines recently is Betelgeuse – it has dimmed significantly over the last few weeks, and there is speculation that it is about to go supernova. On 6th January this year, AAVSO put out a bulletin urging their observers to get photometric and spectroscopic observations urgently. Looking at the light curve from AAVSO over the last 10 years, Betelgeuse has definitely dimmed and is less than 30% as bright as it was early in 2019. Whether this indicates that it is about to blow is not certain though. Another explanation is that it has puffed out stellar winds in our direction that are laden with dust (this type of star is known to do that). Watch this space!

Betelgeuse and Minimum graph




Betelgeuse and Minimum graph

Launching Satellite Clusters

Another significant item is the recent launch of a cluster of 60 250kg satellites, as part of an eventual network of thousands to provide broadband across the planet. Early examples are already affecting astrophotography and are visible to the naked eye. The longer-term effect on ground-based astronomy and astrophotography is not looking good at the moment. On 8th of this month, the American Astronomical Society (AAS) held a meeting to discuss the scheme and its implications, and it is understood that the Royal Astronomical Society (RAS) has put together a working group with a similar aim. Whether this is in time to mitigate the worst impacts remains to be seen.

The Transiting Exoplanet Survey Satellite (TESS)

On a brighter note, the TESS satellite has discovered a rocky planet (TOI 700d) around an M-class dwarf star about 100 ly distant, which orbits within the star’s habitable zone. This star was mistaken for a The sun-like star initially, but a team including a high-school student put this right. The star appears to suffer fewer violent flares than other similar stars, so the prospects for conditions favourable to life on this planet are greater.

Alston observatory workshop and lectures

Closer to home, UCLAN is running free astrophotography workshops at their Alston observatory. The official closing date for applications is 16th January. See details.

Also, UCLAN is holding their next public astronomy lecture on Friday 24th January. Details to follow.

Meteorite Zoo by guest speaker Mike Armstrong LaMAS

Mike Armstrong began with a brief history of meteorites. They have been recognised in the history of most cultures. Except for Europe, surprisingly, a meteorite was appreciated as being from beyond the sky. American Indians venerated a Meteorite from the sky despite its having fallen pre-ice-age. The issue in Europe would seem to be that nothing could stray from perfect heaven down to corrupt earth before the Copernican Revolution.

A modern definition is a piece of rock from outer space (a meteoroid) that survives an entry through the atmosphere (a meteor) to land on the surface of the Earth when it becomes a Meteorite. If less than 2mm a meteorite is classified as a micrometeorite. An average two will be found in the dust and debris on a roof.

Chondrite Meteorite

Chondrite Meteorite

Mike illustrated the breakdown of meteorite categories. Most meteorites are stony chondrites originating in the formation of the solar system. A full classification is complex.

All can be identified by the evidently melted surface from vaporisation during entry. The shape most often can fit into three categories resulting from the dynamics of the entry; spin will be conical (similar to a nose-cone heat shield), an unperturbed fall leaves less melting on the top whereas a tumbling rock will show erratic melting marks like a thumbprint.

Mike went on to illustrate famous meteorites and meteor craters. Surprisingly, the Barringer Meteorite Crater in Arizona and the Tunguska event in Russia was most probably airborne vaporising, explosions leaving no solid remains.

Barringer Crater, Arizona


Barringer Crater, Arizona

Russian Meteor explosion Site




Russian Meteor explosion Site

The best chance of finding a meteor is after a witnessing a fireball and a sonic bang (up to 20 miles distant). An elliptical, Strewn Field fall area may be evident where the smaller meteorites are to one end indicating the direction of fall.

Otherwise, meteorites may be purchased from £30.

Only two direct hits on humans have been recorded though property has been damaged.

Notes and links from the December 2019 meeting

Welcome and Notices Ian Bradley EAS

Ian welcomed members, new members and made a presentation:

Presentation to Anna Hall

Ian made a presentation to our host Museum Curator of long service. Anna has opened up the premises, making tea, sitting through meetings to lock up after we leave for more than a decade until recently.

Anna Hall

Announcements

  • A Skywatcher HEQ5 Pro mount and tripod are for sale – please express your interest through our EAS Contact Page.

Sky Notes for December 2019 – Moira Greenhalgh EAS

After sunset at around 7 pm the Moon, Saturn and Jupiter float in a line above the southern horizon. Moira guided us to the location of the 5.7 magnitude planet Uranus that is worth the effort even with low-powered equipment for its pure colour:


Uranus – NASA/JPL-Caltech

Moira drew our attention to The Square of Pegasus which still rides high in the sky in the evening before Orion becomes prominent in midwinter. In particular, the local galaxy Andromeda, the only galaxy visible to the average person’s unaided eye (See quiz, below).

See also our EAS Sky notes for December.

Quiz – set by David Glass and Richard Rae EAS

David organised use into teams of three and challenged the meeting to two sets of 20 questions. Contrary to the fear that David would challenge us with solutions to his latest research, there was a distinct orientation in favour of practical astronomy, previous EAS talks and what ought to be common knowledge.

So, what is the farthest object visible to the unaided eye? Before going through a list the thousands of visible stars (which are all in our own galaxy)- see Sky Notes above.

Social Evening

While David calculated the overall winners the second half of the meeting broke up into a social evening with fare kindly laid on by hardworking members and the museum curator.

Notes and links from the November 2019 meeting

Welcome and Notices Moira Greenhalgh EAS

Moira welcomed members, new members and announced notices:

Sky Notes for November 2019 – Richard Rae EAS

After sunset at around 7 pm the Moon, Saturn and Jupiter float in a line above the southern horizon. Inside the Summer Triangle, the constellation of Cygnus holds numerous interesting objects – see our Sky Notes for October 2019 for more detail and an October challenge.

Astronomy News Phil Morris EAS

SpaceBit founder Pavlo Tanasyuk holding a life-size working model of the rover

SpaceBit founder Pavlo Tanasyuk holding a life-size working model of the rover

SpaceBit – UK’s first lunar rover

The UK’s first moon rover – and the world’s smallest – will blast off into space in 2021.

Equipped with four legs rather than wheels or tracks, the rover will hitch a ride off of a NASA launch and be able to explore parts of the moon other landers cannot reach.

See Sky News on UK’s first moon rover.

Boris

The first interstellar (from outside the Solar System) comet has been discovered by Ukrainian amateur astronomer Gennady Borisov with a 650mm telescope. Closest approach will be at perihelion on the 8th of December.

The trajectory of comet C/2019 Q4.

The trajectory of comet C/2019 Q4.

See Comet 2IBorisov

Exoplanet

In a paper published at the end of October, an Italian team have used the radial velocity technique to identify another exoplanet in the red-dwarf binary system known as Groombridge 34 about 11.6 light years away from Earth. This one is 36 times the mass of the Earth, and has a period of 21 years. A Super Neptune.

A new category of Black Hole?

We currently theorise two types of black hole: stellar and supermassive. A new discovery by two teams of astronomers, including one from NASA’s Goddard Space Flight Centre, suggests there may be a third type. Called an “intermediate black hole” its mass is somewhere between the other two, but there is no known process that that would form a black hole of this size.

See also: NASA’s Goddard Space Centre’s New Kind of Black Hole

The origin of the heavy elements in neutron star merges

In our last meeting, we heard from Dr Sue Bowler of the University of Leeds about gravitational waves. Phil spotted an update about how that research enables us to test our theories.

Back in 2017 gravitational waves were detected from the merger of two neutron stars. This merger blew away an expanding shell of debris moving at nearly 30% of the speed of light. In one second 10 to the power 22 neutrons passed through an area of 1 square centimetre. This was one of the few gravitational events for which a light source was identified.

Researchers from the University of Copenhagen have now reanalysed spectroscopically the light in the 2017 data and have identified about 5-Earth masses of STRONTIUM (Atomic Number 38) produced in the explosion.

So we now have evidence to support the theory of how heavier elements form.

See more: Heavy element creation confirmed in neutron star merger

DESI

The Dark Energy Spectroscopic Instrument, DESI , will make measurements dark energy. dark energy makes up 68% of the total energy budget of the universe responsible for the accelerating expansion of the universe. By accurately measuring the expansion history over the past 11 billion years, DESI’s scientific goal is to constrain possible models of dark energy. In order to accomplish this goal, DESI will measure the position and receding velocity of about 40 million galaxies

Kielder Star camp photographs from Stuart Atkinson EAS

Stuart Atkinson displayed some of the Astro-photographs taken with a telephoto lens, some with a tripod and tracker:

The Milky Way

The Milky Way

The Pleiades

The Pleiades

The Andromeda nebula

The Andromeda nebula

Observing with IRAM 30m Telescope and JCMT David Glass EAS

JCMT, Mauna Kea, Hawaii (David Glass)

David Glass gave a talk on his observing visits to the James Clerk Maxwell Telescope (JCMT) in Hawaii and the IRAM 30m telescope in Spain. These telescopes operate at mm and sub-mm wavelengths, and David began with an explanation of what can be observed at these wavelengths and what can be learned.

Dinosaur toy looking after the observer's station at the JCMT (David Glass)

Dinosaur looking after the observer’s station at the JCMT (David Glass)

David’s research is looking at the cool interstellar medium (ISM) in early-type galaxies, which can be observed with these telescopes. David went to the JCMT in April, and after explaining how the telescope operates he took us through the practicalities of observing with this telescope.

He then did the same for his visit in July to the IRAM 30m telescope, where the visiting observer is in the “hot seat”. The observer is responsible for setting up the telescope correctly and for carrying out the observations to meet specifications. Overall, observing with these telescopes is hard work but very rewarding. David now has science data from the IRAM 30m telescope which he is examining as part of his research.

IRAM 30m telescope, Pico Veleta, Spain (David Glass)

Notes and Links from the October 2019 Meeting

Welcome and Notices Ian Bradley

Ian welcomed members and announced notices:
  • A 6″ Sky Watcher telescope and equatorial tripod has been offered sale – contact for details through the website
  • A visit to Alston Observatory, Preston will meet at the Observatory at 7:00 PM on Tuesday 29th October. A meal at the nearby White Bull immediately before will be optional.

Sky Notes for October 2019 – David Glass

After sunset at around 7 pm the Moon, Saturn and Jupiter float in a line above the southern horizon. Inside the Summer Triangle, the constellation of Cygnus holds numerous interesting objects – see our Sky Notes for October 2019 for more detail and an October challenge.

Astronomy News Phil Morris

Juno

After abandoning a manoeuvre into a 14 day orbit, NASA decided to bring the perihelion of the 53 day orbit of Juno into closer proximity to Jupiter next month. After the recent failure of the main engine, for ten hours from the 30th September NASA burned the Juno thrusters to bring the craft closer when behind Jupiter. Thus, the solar-powered craft will spend less time out of the sun with its batteries at low temperatures.

See Juno’s discovery of a Great Blue Spot in last month’s news.

Proto-galaxy SSA22

12 billion light-years away, the illumination from galaxy SSA22 is being used to detect large-scale filaments of low-density hydrogen and Dark Matter between which galaxy formation is suspected to occur.

Planet 9 or a black hole

A dozen Trans-Neptunian Objects have all been determined to have perihelions all at the same location. So could it be that a goliath planet, some 5 to 15 times the mass of the Earth is hiding far beyond Pluto, and shepherding these TNO’s into their unusual orbit? In a paper posted on 24 th September, a study claims that rather than a planet, the culprit is a primordial black hole. These are predicted to have formed within the first few fractions of a second after the big bang, but their existence has never been confirmed.

The Optical Gravitational Lensing Experiment (OGLE) is looking for gravitational microlensing events. If the alignment is perfect, a heavy foreground object acts as a lens, distorting and amplifying the light from the object behind it. After 5 years’ of observations, researchers uncovered six strange microlensing events that seem to have occurred when objects roughly 0.5 to 20 times the Earth’s mass acted as a gravitational lens.

The paper says:
“Capture of a free-floating planet is the leading explanation for the origin of Planet 9. We show that the probability of capturing a primordial black hole instead is comparable”

Such a captured black hole roaming the outer solar system would influence the orbits of TNO’s in exactly the same way as Planet 9.

The Promise of Gravitational Waves, Dr Sue Bowler, University of Leeds, RAS, editor Astronomy and Geophysics journal

Dr Bowler gave an easily understood and entertaining talk illustrated with images of Gravitational-wave detectors a Laser Interferometer Gravitational-Wave Observatory) ( LIGO ) and Virgo

Virgo Observator at Caltech.

Virgo Observatory Pisa, Italy. Credit: The Virgo Collaboration/CCO 1.0

Our current way of detecting a gravitational wave is by detecting changes in length caused by the wave stressing space-time as it passes by. Dr Bowler warned of likening the electromagnetic waves in astronomy with gravitational waves in space-time – gravitational waves are more like pressures waves, compressions of space-time. Nonetheless, the classic Michelson–Morley interferometer configuration put us on familiar ground as the basis of a LIGO layout of two mirrors at right-angles reflecting a spilt beam back to the source. The interference pattern shows any change in the distance travelled in the two directions. The interferometer arms are each 4km long but with the laser beam bouncing many times along each arm before the two beams interfere, the effective length is nearer 1200km. The system is so effective, it can detect changes in length of 10-19m, that is one 10,000th of the diameter of a proton! The technical design challenge is reducing the background noise – people, vehicles, earthquakes… – to allow such tiny changes to be seen.

Over 30 gravitational wave events have now been detected – they have to be seen by both current LIGO detectors Hanford and Livingston. All but one are believed to be created by the merger of two black holes in the final fraction of a second. The rapidly changing orbital situation before they coalesce produces a rapidly fluctuating wave with increasing frequency and amplitude. This produces the detected chirp lasting about 0.2 second. The physics of two such massive objects just before they spin into their combined event horizon is unknown and the subject of research. The other event is a much longer ‘chirp’ event, duration ~100 seconds, is believed to be the merger of two neutron stars. A burst of gamma rays was detected 1.7 seconds later from the resulting ‘kilonova’ enabling precise positional information. Additional gravitational wave detectors are necessary to provide better positional information on black-hole mergers – currently only about 10 degrees – and many are now in construction.

For more information see: