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#168 - Full Exoplanet Enshrouded Lovers

This week we talk about enshrouded dust clouds around the galactic core and a new exoplanet at the centre of the milky way, plus loads more space news.




I wonder why. I wonder why.

I wonder why I wonder.

I wonder why I wonder why

I wonder why I wonder!

Richard Feynman.










OTD in 1997 January 17th the Delta II rocket carrying GPS IIR-1 - Thirteen seconds later, the rocket's flight termination system was activated by the onboard computer. detonating explosive charges aboard the rocket, only ½ Km above the launch complex. Caused by a crack in the solid rocket motor casing,

The upper stages were blasted free, and a manual destruct was activated from the ground, the payload was still intact till it hit the ground.

Some debris landed around the launch pad, in the parking lot outside the complex blockhouse, destroying twenty cars. Two hundred and fifty tons of debris fell within 3,000 feet (910 m) of the launch pad. Residents of the area around the launch site were advised to stay indoors. The explosion was reported to have been felt 25 miles (40 km) away from the launch site, and damage to store windows 10 miles (16 km) away was reported




THIS WEEK



The $10billion SLS core stage finished and packed up and ready for transport down to Stennis in Mississippi on a barge called the Pegasus all 64 metres of it!! It is a beast, and the photos of the behemoth were pretty cool.


UK SPACE ORBEX NEWS


A well-respected launch integration provider in the US is coming into the UK space market TriSept Corporation announced on 14 January 2020 that it has procured a full mission aboard The Maiden Orbex Prime launch set to lift off in the autumn of 2022 from the UK’s first spaceport in Sutherland, Scotland. A multiple spacecraft manifest for a dedicated rideshare mission enabling the launch of more than 200 satellites on 70 different missions aboard 20 different launch vehicles from 13 launch sites across the globe. TriSept will also have a full-time presence at the Harwell Space Campus in Oxford, near the Spacestore.




Crew Dragon has a BIG test on Saturday, the in-flight abort test. A Falcon 9 on its 4th flight, will carry the crew dragon to 21Km, chosen as this is a critical time for an abort, then the Crew Dragon SuperDraco boosters will drag the capsule away, probably damaging the Falson 9 so it will break up. The second stage of which has had it’s a Merlin Engine removed and replaced with some block similar in weight. SpaceX will also send its own recovery boat to meet the crewless dragon, as in a real emergency. Two NASA astronauts, Bob Behnken and Doug Hurley will be watching intently.


Full Moon Lovers

The weird story of the week was Japanese billionaire Yusaku Maezawa launching his tinder-like a campaign to find a girlfriend for his #dearmoon flight around the moon. A contest, ala miss world, or miss out of this world, will be a Japanese reality show called “Full Moon Lovers”. Open to single women interested in going to space, over the age of 20, who want world peace. His tweet was retweeted 4 million times, with a billion yen.(£7 million) split between 1000 random tweeters!!!! So that cost £1.75 a retweet? “With that future partner of mine, I want to shout our love and world peace from outer space,”



The turtles Graduated, NASA and Canada’s newest class of astronaut candidates, “They represent the first wave of NASA’s Artemis generation astronauts,” NASA administrator Jim Bridenstine. seven men and six women down from 18300 submissions in 2016. The previous cohort the 8 balls include Christina Koch and Jessica Meir who have just completed the second all-female spacewalk.



Also in India four astronauts shortlisted for the Gaganyaan project, India’s first manned space mission, will receive training in Russia for 11 months, then the astronauts will receive module-specific training in India. trained in crew and service module designed by ISRO, learn to operate it, work around it and do simulations, India’s heaviest launch vehicle Bahubali GSLV Mark-III will carry the astronauts to space in 2022 the 75th year of Independence.



Exoplanet Delight.

Our nearest neighbouring star, Proxima Centauri,4.2ly away (a mere 25,000,000,000,000 0r 25 trillion miles away) as discussed on an early podcast hosts a temperate terrestrial planet. However, Mario Damasso and a team from all around the world, detected in radial velocities evidence of a possible second planet with a mass roughly 6 times that of earth and with its orbit taking about 5 years.

This is not certain and requires to be followed up but it’s looking pretty convincing. The scientists show that the existence of the planet can be locked in, and its true mass determined with high accuracy if astronomers can combine the Gaia astrometry and radial velocities. Proxima c could become a prime target for characterization with next-generation James Webb and the mega large terrestrial telescopes as its orbit takes it far enough away from the glare of the parent star, from our point of view, to study closely. Excitingly this candidate planet represents a challenge for the models of super-Earth formation and evolution. I don’t know why no one had done this before all they had to do was analyze the enlarged radial velocity dataset spanning 17 years by performing Monte Carlo analyses in a Bayesian framework using models based on Gaussian process regression.



Bizarre objects at the centre of the galaxy.

(Credit: Illustration: NASA/CXC/M.Weiss)

The centre of our galaxy is such an extreme place, everything is ridiculously extreme, velocities, magnetic fields, bending of spacetime, so the large hadron collider is to physics, the centre of the galaxy is to astronomers.

Some new exotic objects are examined in “A population of dust-enshrouded objects orbiting the Galactic black hole” by Anna Ciurlo and international team of scientists published in Nature.

The centre of our galaxy has a density of stars 1 billion times higher than our own suburb of the Milky way, an area that is too small to host Solar System and the Proxima system, and at the centre lurks the supermassive black hole Sagittarius A* and a cluster of young, massive stars (the S stars) and various gaseous features. .

In the last decade, two unusual objects were found to be closely orbiting Sagittarius A*: the so-called G sources, G1 and G2. These objects are unresolved and blurry having a small size of the order of 100 astronomical units, and they show both thermal dust emission and line emission from ionized gas. G2 looked like it was going to be torn to shreds when it’s orbit took it very close to the SMBH in 2014, this should have been spectacular as the material would have created a blazing blast of energy as the material was ripped into further shreds by the accretion disc of the black hole. But this never happened, and G2 passed by, in the Cosmic fizzle. and after being stretched out, appears to be becoming more ball-shaped again, so both G1 and G2 have generated attention because they appear to be tidally interacting with the supermassive Galactic black hole, possibly enhancing its accretion activity. But amazingly no broad consensus has yet been reached concerning their nature: the G objects seem to half gas/dust cloud half Star. Andrea Ghez one of the greatest astronomers working today, if not one of the greatest scientist, and co-author of the paper describes them "These objects look like gas and behave like stars,"

Using the Keck Observatory in Hawaii, the researchers have found four additional G objects, all lying within a heartbeat of the black hole and they are a type of object, that is probably unique to this environment. The widely varying orbits show the six G objects may have a formed in the same way but as separate events. They have very different paths from each other around SgrA*, with orbital periods ranging from 170 to 1,600 years.

How are they formed Anna Ciurlo said back in June 2018 that it starts with binary stars orbiting an SMBH, the black hole perturbs them so they move close enough to touch, "they kiss each other" and then they merge. "Then this couple is melted together." This merger takes millions of years to complete, and the merger causes a vast cloud around the new stella object. This messy pigpen cloud is obscuring the light from the new star.

Being in this extreme corner of the Galaxy makes this process far more likely, so we should see more objects like this.

Stefan Gillesson who works at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany who discovered G2 in the first place, thinks this paper is ace but is less sure about the merging star hypothesis. “Out of the 40 stars we are seeing in the galactic centre, we have six mergers,” he says. “That means that unless these mergers are very long-lived, you immediately start overproducing the number of stars which should be there.” So to be seeing the shortlived (million year) aftermath of 6 of the 40 seems very unlikely considering the galactic scale of time of billions of years.

Ciurlo counters that the most recent burst of star formation near SgrA* is thought to have occurred about 5 million years ago. “These types of mergers tend to happen quite early once you form stars,” Ciurlo says. “So we only see the mergers that happened at the beginning, soon after the stellar population formed.”

Gillessen thinks we may have the answer to the conundrum soon if indeed this is a star hidden in a gas cloud, G2 stellar Core will be rolling it’s way around the deep gravity well of SgrA* in a very different way to the shroud of gas that surrounds it, so they will pull apart leaving the case clear for a Ciurlo win.


Space Fact - Is the Solar system stable!!

The Solar System is far from the static clockwork imagined by the ancients moving forever from the infinite past to the infinite future. The moon may be the most stunning testament to that.

The dynamics of the Solar System change over time close encounters and regular orbital similarities (Resonances, like the chords strum on a guitar) can amplify these changes:

Close encounters re-arrange orbits giving huge and quick changes, maybe flinging bodies out of the Solar System. The resonances destabilize small-body orbits, depopulating some orbits, for example, the Ring Gaps around Saturn. Some resonances are stable, Pluto is in a 2:3 Resonance with Neptune ie Pluto completes 2 orbits for every 3 orbits of Neptune another effect of resonance is objects swept into them can form distinct dynamical "families" of objects. All of these effects have helped "shape" the Solar System over its long history.

So Sven sent in this little article from a german blog. Which shows that although the solar system seams stable chaos may lurk around the corner.



Using an equation of Orbital parameters of two planets, in relationship to the change in the semi-major axis of a planet's orbit, the mean distance between the star and the celestial body. If this mean-distance changes too much over time, the orbit of the planets can cross and collisions are possible.

Although this is a really gnarly and pretty unsolvable differential equation, you can use the power series to get estimations for it. Looking at the Equation you can see n1 and n2 which are the mean orbital periods of the 2 planets are extremely important because if these values add up to be a tiny number the dreaded change in mean semi-major axis becomes dangerously large, we are gonna get the orbits swinging out into the path of other planets!! Of course, this happens when you have resonances, orbital periods are related by a ratio of small integers of the orbits, and at some point, these integers sum to zero as you iterate through.. Fortunately, in our solar system, these "resonances" in recent years have not created problems. But because they can always occur in principle and because the orbits change slightly over time, you can never completely rule out that the disruptions will extend beyond all limits, even for very long periods of time. Chaos always lurks behind order

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