Robert Inventor

Short summary: it's an entertaining but rather far fetched proposal in an arxiv preprint not published anywhere but mentioned in a Scientific American op ed. Implausible for many reasons including its spectrum which is not the shiny spectrum you'd expect from a solar sail but the red of tholins mixed with rock and metal as you'd expect from an asteroid / comet.

I am getting many people contacting me scared of this asteroid, which was proved to miss Earth back on 1st August 2002! Right now, it is coming from below Earth's orbit, but not directly towards us. We are circling the sun at the same time. It crosses Earth's orbit ahead of us. By the time we get to the place where our orbits cross, it is already high above our orbit and moving away. It will be closest on 13th January, but even then it is at a vast distance of 61 million kilometers away. We already knew this back on 29 July, 2002,

This is a rather fun idea by Peter Koch originally suggested in the Moon Miner's Manifest Classics - 1987-1988 (see page 31). It's not so likely in the early stages, because of the large amounts of water needed to construct it, but it may perhaps be of great value at a later stage, especially for bases that have a lot of traffic in and out. If the liquid is water, it has to be over sixty meters deep (62.3 meters), to equalize the pressure inside and outside the habitat. The depth can be much less, if it is a denser fluid. You then don't need any doors but can just dive through it and come out on the surface of the Moon.

The basic message of the IPCC report is that we need to act now before 2040, to avoid more expensive mitigation measures in the last 60 years of the century. The worst effects are for 2100. And that if we aim for 1.5°C, it is far better than 2 °C.

Just before the flyby of Pluto by New Horizons I wrote a speculative fun article about whether it could spot moonlets of Pluto’s moons. Can Moons Have Moons? Or Rings? Theoretically it seems possible that moonlets just possibly might be dynamically stable, there as with many of the moons of our solar system such as the more distant moons in the Saturn system.

Does this discovery of 'The Goblin make 'Planet 9' more likely? Yes I’d say so. It’s looking really strange. I’m beginning to be won around to the idea :). There is plenty of space for planets to exist beyond Neptune. No known big gas giants to get in their way. And - objects get far far fainter the further they are from the sun. It was hard to find, even though it was only 80 au from the Sun - at it's furhest it would be 2300 au away. They spotted it first in 2015 and it's taken since then to figure out its orbit.

People often ask, "How close are we to sending humans to Mars" and it's not surprising given the optimistic presentations by Elon Musk and others. However, Mars is just too far away to send humans at this stage.

This originated as my answer to a question on the Quora question and answer site: "In what general knowledge domains do alternatives to Wikipedia exist that are significantly superior?". Of course there are examples of much better specialist encyclopedias for various knowledge domains. But you can also do better than Wikipedia using content derived from Wikipedia itself. I think my own new wikis are an example of this, for a simple reason. Because we can fix various errors that can't be fixed there and add new content that can't be added there.

If you search Wikipedia for present day habitats on Mars, then you will find many articles about Mars colonization, but on the idea that there might be microhabitats for present day life there, you'll find almost nothing. You'll find my Present day Mars habitability analogue environments on Earth but nothing about the possible habitats they are analogues of. So why is this? Well there was an article on this until just a week or two ago, but it is now deleted.

This is scaring some people - because they describe dramatic things that could happen like floods tens of meters deep, and the world too hot for humans. Most of this is for far into the future. The sea rising 10s of meters would be thousands of years into the future - many of the news stories didn’t make that clear.

Trump has had a lot of criticism after the summit, with many saying he conceded too much to Kim. I don’t think he did at all myself. The main thing he gave him was a meeting with him, and a couple of days of his time. And he built trust. He thinks that’s important. Previous presidents didn’t think it was important, they proceeded on a basis of distrust. He is trying something new.

Short summary: This is a first paper in what they hope to be a long term study. It’s an interesting project, but it should not be used to predict what will happen to Earth in the future. Instead we should rely on projections by the scientists who are studying the effects of climate change, our population growth, predicting food security and looking at the intricate details of how our world works. The UN population division says as its middle of range projection that we level off at 11 billion people by 2100 and experts say we can feed everyone too, if we continue on target with the things we are doing to make sure it happens.