Gfamily

A recent xkcd (if you're not familiar with xkcd, you can thank me later) https://xkcd.com/2849/

The campsite at Bellingham in Northumbria is being converted to being astro friendly with lighting being reduced where possible. They occasionally run star gazing weekends, though I understand they're very popular and book out quickly. There's a small Dob in the reception that can be borrowed. Our nights there were very wet, though we had one evening where were we chasing stars and planets through gaps in the clouds; never more than 2 or 3 minutes viewing for any single target though. But very dark skies (as you'd expect from a site near to Keilder).

Lol - I was going to say "Oh, and look out for the grazing occultation of that star (HD104864) " - but ... it's only 10th magnitude it's a blooming daytime occultation. Probably not then.

Yes, Venus should be easily visible - and I suspect that the surface brightness may be even brighter than the Moon's occulting edge* *The moon's surface is fairly dark - with an albedo of about 12% it's similar to used asphalt in reflectivity - whereas Venus' clouds have a much higher albedo, reflecting up to 70% of the Sun's light.

I know the pinned post from @Stu suggests that this forum is for 'less predictable' events, but looking at other threads, I see that's a guideline rather than a rule (apologies). Just to flag up that there's a daytime occultation of Venus by the Moon on the morning of Thursday 9th November. In my location it starts at about 9.40am and Venus will re-emerge about an hour later. Totally predictable and totally off topic, but might be of interest if people are free. Helpfully, Venus will be easy to find just beforehand as the Moon will be right next to it

Unless there has been a process to differentiate and concentrate the gold from the mix, having to extract the gold is where the problem would lie. On Earth, economic extraction depends on finding veins created where subterranean hydrothermal flows have different metallic elements dropping out of the superheated water at specific pressure and temperature ranges. We know that there's billions of tonnes of gold in the oceans, but it's having a cost effective means of extraction (i.e. differentiation) that determines whether it's a valuable ore or not.

The issue as I see it, is that measuring density of individual asteroids is more than a bit tricky. It essentially comes down to measuring the perturbation of the asteroid as it is approached by other asteroids or planets (assuming you know the mass of the other). There are some asteroids for which we do have reliable masses, which are generally consistent - S type asteroids having lower density than M type asteroids. Of course, those to which we have sent missions have very precise masses - and Dawn visited both Ceres and Vesta (S type and M type respectively). On the basis that we have meteor remains that have densities that correspond to those of well established asteroids, we don't have a problem with most of them. Nothing so far suggests that there is anything to support the idea of 'elements unknown to science' being part of asteroid 33 Polyhymnia.

As far as I can tell, there is no good knowledge of the mass of the asteroid. The best estimate comes from a mathematical model of the solar system that interprets ephemeris data to determine how interactions between Asteroids allow calculations of masses The asteroid itself is included in the paper for the 2010 version of the model (though that itself notes that the mass is 'unrealistic'). Later iterations of the paper do not include the asteroid in their tabulations. Using a clearly unreasonable value for the mass as a basis for hypothesising the existence of ultradense matter (almost 4x the density of the most dense element) is umm, a stretch! A paper containing the density calculation https://arxiv.org/pdf/1203.4336.pdf Another paper giving the tabulated mass (not included in later versions) https://arxiv.org/pdf/1011.4419.pdf

I believe the film (not necessarily the best film ever, but one of many people's top 5) is available on the Channel 4 Catch Up service for the next few days. Spoiler for the Film Name under this link ETA - Ooops, accidentally given away that it's associated with a film.

Can you find some elsewhere? They look similar to those used in better made cassette tapes.

Not sure about whether people take their own scopes I understand that High Legh openng depends on the weather, but if you go to their website you can send them your phone number and they'll put you on a list to be messaged if they're running a Friday evening session. It's a bit further away for you, but I know that Liverpool AS always meet at Pex Hill (Widnes) observatory on Wednesday evenings, and people do take their own gear.

Hi Rob Depending on where you are in Cheshire, you may well find yourself local to one of several Astronomy Societies, which can be a good way of finding fellow astronomy enthusiasts. There are clubs in - Chester, Macclesfield, High Legh, Wincham & Pickmere and South Cheshire and my own club, the Mid Cheshire Astro Group who meet near Delamere Forest. If you look on the excellent GoStargazing.co.uk website you can see where and when they meet. https://gostargazing.co.uk/stargazing-events-future/

The RSPB are looking to know more about the practice, and have set up a website where you can let them know about where there have been heather burns. https://upland-burning-rspb.hub.arcgis.com/pages/report-a-burn

It looks like the Brian Cox / Jeff Forshaw book is down to 99p on Google Play Books for today anyway.

No problem - BTW, well done on the 'place appropriate' name of your observatory - like like like !

The interview includes a comment that the number of PNs is significantly lower than would be expected given the population of suitably sized red giant stars. If I heard it correctly, if almost all red giants of the right size were to generate a PN, we'd expect to see far more of them. Also, (admittedly less convincingly) the observation is made that if the first two PNs studied by JWST show that a multiple star system is required to explain their structure (structure that was not previously obvious), then it may be more than a coincidence. But given the populations argument above, it may indeed be more than a coincidence. Hence, further analysis is required.

Details from the Liverpool AS website https://liverpoolas.org/event/martin-mere-wwt-star-party/ Details from the WWT/Martin Mere website https://www.wwt.org.uk/wetland-centres/martin-mere/whats-on/star-party-with-liverpool-astronomical-society Booking required - tickets £10.

When do Planetary Nebulae form? I've always read of them as being the last stage of smaller Red Giant stars; their outer layers being puffed off at their end of life. However, a listen to a recent Awesome Astronomy Podcast seems to suggest that 'it's a bit more complicated than that'. An interview with Dr Robert Wesson covered the results of the JWST imaging of the Southern Ring Nebula (one of the Initial Release images) and more recent imaging of M57 'our' Ring Nebula. An article here about the JWST results that Dr Robert Wesson worked on, suggesting that PNs form within multiple star systems. https://scitechdaily.com/webb-space-telescope-reveals-mysterious-arcs-intricate-details-in-the-remains-of-a-dying-star/ and a copy of the recent paper on Arxiv. https://arxiv.org/pdf/2308.09027.pdf Further investigations are clearly required

Ok I've used astrometry to identify the three brightest stars as HD199770 HD197407 HD197559

Can you give the RA/Dec ?

Photo on PC desktop (imaged after a Lovell Lecture talk) Image on Laptop (using an 'oil painting' filter)

Yes, took advantage of an offer a couple of years ago and look forward to getting the bi-monthly magazine, which has articles for the different special groups as well as a section for young astronomers. It usually has up-to-date news on research etc, so is valuable in that regard. One difference to the 'newsagent' monthly magazines is that it's very light on adverts - which, is likely to appeal to some readers.

Just to be clear, (and apologies if this is obvious), the t adapter has two parts - one is a ring with the internal t-thread, the other will be specific to your camera mount. You buy them both together If you do an ebay search for " t mount for <insert camera make and model here>" you will get the one you want.

It makes more sense (or at least, it's easier to see what's going on) if you use this ESA slider image that shows both the NIRCam image (as above) and the MIRI image. https://esawebb.org/images/comparisons/potm2307/