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NEAF is back for 2023! The world's largest telescope and astro equipment expo back for the first in-person event since the pandemic. BINTEL is attending NEAF (Northeast Astronomy Forum and Space Expo) in the USA and will be reporting from the exhibition.  Check in here from Sunday 16th April for all the latest news and cool gizmos.   Celestron StarSense Autoguider Handles polar alignment and then guides your mount! Celestron SkyMaster Pro Binoculars These new ED binoculars allow you to use standard 1.25 inch filters for Lunar viewing. Tele Vue stand ZWO   John from BINTEL with Memory Li from ZWO going through the new ZWO mounts, refractors and Seestar S50 smart telescope.

More magic from the James Webb Space Telescope (JWST) The planet Uranus and its rings. First observed via telescope in 1781 by astronomer William Herschel, Uranus is the seventh planet in the Solar System was the first one we learned about in modern times. The others - Mercury, Venus, Mars, Jupiter, and Saturn - had all been familiar to ancient peoples across the world. Uranus is visible in telescopes as a small, greenish-blue hue and under ideal conditions, might be able to be spotted under a dark sky if you have great eyesight. Like all the gas giants in the Solar System, Uranus has a ring system surrounding the planet. The rings around Uranus were discovered by accident in 1977 by astronomers who were looking into the planet's atmosphere. They've been imaged from Earth once before using the Keck telescope and from space as Voyager 2 flew past the planet, but never in such detail as this recent JWST image. Apart from the amazing image of the rings themselves, JWST has also captured the polar cap which unlike anywhere in the Solar System is on the side of the planet - not at the poles. This is because Uranus orbits the Sun tilted on its side, resulting in the longest and most extreme seasons of anywhere in the Solar System. It's thought that Uranus is tilted this way due to an impact with a rocky body about one to three time the size of the Earth sometime in the early formation of Solar System. While JWST is delivering groundbreaking data which will help us better understand and, in some cases, rethink the nature of the large scale structure of the Universe, our largest space-based telescope will also help us learn about our Solar System. Supernova remnant Cassiopeia A (Cas A) When stars over certain size reach the end of their lives, they explode in a massive event called a Supernova. The evolution of a star leading up to this event are fascinating and the leftover remnants are some of the more spectacular objects in the sky. Our own Sun will explode as Supernova in about 10 billion years, after becoming a Red Giant in some 5 billion years. (Note to self - add both dates to the BINTEL Astro Calendar....) The striking colours in this JWST image of Cas A are infrared light which has been translated to the visual colours we can see with our eyes.  Cas A has been studied with ground-based telescopes as well as Hubble and is the closest Supernova remnant to the Earth resulting from the explosion of a massive star. Why Supernova remnants are important.  One of the reasons we observe Supernova remnants is to learn about cosmic "dust". This is made up of heavier elements than hydrogen and helium and tiny particles of it are distributed into interstellar space during a supernova. It then clumps together over vast periods of time under the influence of gravity, where it forms planets and even us! Yes - the hard matter around you was once part of a supernova explosion.  One problem we hope to solve is that we can't reconcile the amount of dust we see in early galaxies. Careful studies of objects like Cas A might help us understand how the world around us came into existence. New Star Formation and Galactic Evolution In the weeks leading up to January 2004, the Hubble Space Telescope carefully photographed a small spot in the sky, capturing faint photons for a total of over 11 days taken over 400 orbits. The image produced by combining some 800 exposures is called the Hubble Ultra Deep Field. It shows a vast collection of galaxies of all types, with some of the smaller, red coloured galaxies already formed when the Universe was only about 800 million years old.  Like the earlier Hubble Deep Field image produced in the middle 1990's, the field of view is so narrow, there's almost no stars from our own Milky Way in the foreground. It's basically entirely composed of galaxies. What came from these and subsequent deep-field images - including one taken of the southern skies - was a better appreciation of the early structure of the Universe, that it looks similar in all directions, and that we live a typical place. Now the JWST has imaged the Hubble Ultra Deep Field (UDF) in less than a day instead of the 11 days it took Hubble. By using the JWST NIRCam’s medium-band image filters, it was able to capture more information for better spectroscopic analysis across almost the entire field.  The original Hubble deep field images have been intensely studied over the years and these new JWST images will help add to our knowledge. Plus the fact they were captured in only a fraction of time points to even more amazing views in the coming years. Cheers, Earl White BINTEL 14th APril 2023

Will an asteroid really hit the Earth on Valentine's Day in 2046? Probably not! There's been a lot of press coverage recently about the likelihood of an asteroid impact, like this article from CNN. The short is answer is probably not - but let's look at how we classify dangerous space rocks. What's the Torino Scale?  Following on from some of the articles we're run recently about meteorites, we've been asked some questions about are there any space rocks currently on a collision course with Earth. Until a couple of months ago, there were none. Then a pesky one popped up and we thought it would be a good time to cover how we track asteroids and comets that pose a danger to us. First up - there's nothing immediate to worry about! The Torino scale is a way to measure the threat level that a particular space object poses to the Earth and the various human and non-human critters that live here. It was adopted in 1999. It's rated from 0 to 10. All comets and all asteroids bar one that are whizzing around the Solar System are rated as a 0. This means that there's no chance of them impacting the Earth in a way that would cause damage of any concern. An objected rated as a 10 is a large object that will definitely hit Earth and cause immense damage on a planet wide scale.  This is the sort of impact that caused the extinction of the non-flying dinosaurs. Just how dangerous an object is between 0 and 10 depends on two main factors. One is the chance of hitting the Earth. This is calculated by observing the object over a period of time and then refining its predicted orbit.  Objects initially found on path to hit the Earth that was calculated shortly after their discovery might end up missing us once further observations are made. The other factor that makes up an object's Torino score is the likely energy released by the potential impact. This is stated in Megatons (millions of tonnes of TNT) - the same unit used to describe the power of humanity's most powerful weapon, the Hydrogen or H-Bomb.  Recent impacts such as the Asteroid 2023 CX1 that we wrote about here and which hit on the 13th of February 2023 had an energy of some 300-400 kilotons (.3 to 4. of a Megaton).  The meteor that exploded over Tunguska in Russia in 1908 released about 20-30 Megatons. The event that wiped out the non-flying dinosaurs approx. 65 million years released some 100 million Megatons of energy. 2023 DW - Torino Score of 1 As I'm writing this - 12th March 2023 - there is one object that has a "1" rating on the Torino scale. This means there's a small chance it will hit the Earth and if it does - and there's only a tiny chance it will - the impact event will be significant.  Objects are placed as a level 1 on the Torino Scale a few times a year and always bumped back down to 0 once we learn more about them. Asteroid 2032 DW - if it were to hit the Earth - would impact us on the 14th of February 2046. (NASA supplied illustration of an asteroid.) Based on current orbital data, the chance of 2023 DW hitting Earth on Valentine's Day 2046 is around 600 to 1. This is small chance of happening, but if were to occur, the asteroid would impact us with a similar amount of energy that was released by the Tunguska event in 1908. This asteroid (or possibly small comet fragment) hit a remote area of Siberia where it flattened over 2,000 square kilometres of forest. If it had struck the Earth a few hours later, it might have destroyed Paris or London. Why aren't we more concerned about 2023 DW? First of all, the chance of impact is remote. But more importantly, astro objects that end up at 1 or more on the Torino scale are more likely to be moved back to 0 once more data and observations have been gathered about their movement through the Solar System. This happens several times a year when we discover space rocks that might be headed our way, only to reclassify them as a totally safe, "0" once more data about their predicted orbits are worked out. 2023 DW is very likely to be back to a "0" on the Torino scale by the time you read this. Have we ever spotted anything that posed a really serious threat? There's a been a few, but one stands out in particular.  The asteroid 99942 Apophis spent several days as a "4" on the Torino scale in December 2004. Calculations at the time gave Apophis a nearly 3% chance of hitting the Earth in 2029. As this asteroid is some 370m in size, the damage such an impact could cause would be massive and widespread. Observations of Apophis in the following weeks ruled out an impact in 2029 and based on subsequent data, it's now calculated not be a danger to the Earth for at least another 100 years. The approx. size of asteroid 99942 Apophis compared to the Empire State Building and the Eiffel Tower While 99942 Apophis won't hit the Earth in 2029, it will come close enough to be a seen with just your eyes at around magnitude 3.1. We'll no doubt be mentioning more about in future BINTEL posts closer to the approach.  :) Cheers, Earl White BINTEL 13th March 2023