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## A new dwarf planet found

It was announced last week that the Canada-France-Hawaii Telescope (CFHT) had discovered a new dwarf planet beyond the orbit of Neptune. The planet, provisionally named 2015 RR245 by the International Astronomical Union (IAU), has had its orbit measured over several months and from this it has been determined to have a highly elliptical orbit which brings it to within 34 AUs from the Sun, but takes it out as far as 120 AUs. By comparison, Neptune’s orbit is far closer to circular and at about 30 AUs (varying between 29.8 and 30.3 AUs).

From its current distance and brightness, its size has been estimated to be about 700km in diameter (Pluto, in comparison, has a diameter of 2374 km). This is based on an assumed albedo (reflectivity), so if it is more reflective than assumed it could be smaller, if it is less reflective it could be larger.

The Canada-France-Hawaii Telescope has discovered a new dwarf planet beyond the orbit of Neptune.

2015 RR245 was discovered as part of the Outer Solar System Origins Survey (OSSOS), and was spotted in February 2016 on an image taken in September 2015. We thus have images of it spanning nearly 10 months of its orbit, enough to get a decent idea of its orbital parameters.

If 2015 RR245 is as large as 700km in diameter then it will be amongst the largest dwarf planets known.

As of yet, the IAU has not admitted 2015 RR245 to the select club of official dwarf planets. At the moment, there are only five dwarf planets in this ‘official list’; namely Pluto, Eris, Ceres (in the asteroid belt), Makemake and Haumea. Since the creation of the dwarf planet category in 2006, these five are the only objects which have been classified as such. Haumea was the latest object to be added to the list, in September 2008. We shall have to see whether 2015 RR245 makes the list at some point in the future.

## Robert Kennedy – the mindless menace of violence (speech)

Just over 7 years ago, in early 2009, I bought a CD of some of Robert Kennedy’s greatest speeches. Whilst his brother John F. Kennedy gave some memorable speeches, for me Bobby Kennedy possibly surpassed JFK with his eloquence. One of his most moving and wonderful speeches has been passing through my mind these last two weeks or so; with the senseless shootings of innocent black people by police in the United States, the killing of the five policemen by an assassin in Houston, the horrific terrorist attack in Nice on Bastille Day which has killed at least 84 people, many of them children, and the failed coup in Turkey with over 100 dead. And, just as I was putting this blog together yesterday, the shooting of 3 more police officers in Baton Rouge.

Robert Kennedy (RFK) served as Attonery General under his brother’s Prisidency, but in 1965 he entered the Senate as one of the senators for New York. On 16 March 1968, RFK announced that he would run for the presidency, and set about touring the USA to garner support for his campaign. On the evening of 4 April, he was due to give a speech in Indianapolis when he learnt en-route of the assassination of Martin Luther King. He broke the news to the gathered crowd, many of whom had not heard the news until Bobby Kennedy told them. He gave a very moving and powerful speech on that evening, and I may blog about that particular speech another time.

But, today I am going to share the speech that he gave the day after MLK’s assassination, on 5 April 1968. The speech is entitled “The mindless menace of violence“, and it was delivered at the Cleveland Club in Ohio.

Kennedy toured the country as part of his campaign to become President of the United States, concentrating to a large part on some of the poorest communities in the country, where he met with dissaffected whites, blacks and latinos who had been left behind by the ‘American Dream’.

“this mindless menace of violence in America which again stains our land and every one of our lives.”

It is quite a long speech, nearly 10 minutes long, but bear with it and I think you will be struck by its eloquence. Bobby Kennedy wrote the speech himself, putting it together in the hours after the horror of MLK’s assassination had sunk into his mind.

The speech opens with these lines….

This is a time of shame and sorrow. It is not a day for politics. I have saved this one opportunity to speak briefly to you about this mindless menace of violence in America which again stains our land and every one of our lives.

It is not the concern of any one race. The victims of the violence are black and white, rich and poor, young and old, famous and unknown. They are, most important of all, human beings whom other human beings loved and needed. No one – no matter where he lives or what he does – can be certain who will suffer from some senseless act of bloodshed. And yet it goes on and on.

Why? What has violence ever accomplished? What has it ever created? No martyr’s cause has ever been stilled by his assassin’s bullet.

No wrongs have ever been righted by riots and civil disorders. A sniper is only a coward, not a hero; and an uncontrolled, uncontrollable mob is only the voice of madness, not the voice of the people……

But, Bobby Kennedy was also deeply concerned with the economic disparities in the United States, and with the sickening racism which had profoundly disturbed him. He later goes on to say…

……

For there is another kind of violence, slower but just as deadly, destructive as the shot or the bomb in the night. This is the violence of institutions; indifference and inaction and slow decay. This is the violence that afflicts the poor, that poisons relations between men because their skin has different colors. This is a slow destruction of a child by hunger, and schools without books and homes without heat in the winter.

This is the breaking of a man’s spirit by denying him the chance to stand as a father and as a man among other men. And this too afflicts us all. I have not come here to propose a set of specific remedies nor is there a single set. For a broad and adequate outline we know what must be done.

Followed immediately by these words…

When you teach a man to hate and fear his brother, when you teach that he is a lesser man because of his color or his beliefs or the policies he pursues, when you teach that those who differ from you threaten your freedom or your job or your family, then you also learn to confront others not as fellow citizens but as enemies – to be met not with cooperation but with conquest, to be subjugated and mastered.

The entire text can be found here at the John F. Kennedy presidential library website.

There are several versions of this mesmerising speech on YouTube, but many seem to have had an annoying soundtrack of some music added. I feel the added music detracts from hearing Bobby Kennedy’s words, which are powerful enough and do not need any music to make them more dramatic. So, the version I have included here is just RFK’s incredible words.

What strikes me most when I hear or read these words of Bobby Kennedy is how little progress we have made. One could argue that we have digressed; there are more mass shootings now in the USA than in the 1960s when these words were spoken. There is more terrorism and conflict than ever. And, in the presumptive Republican Party presidential nominee Donald Trump, we have a man who is the very antithesis of the wonderful ideals for which Bobby Kennedy stood.

I would say “enjoy” this video, but I am not sure that one can enjoy this speech. It is moving, harrowing, thought-provoking, upsetting, but also uplifting. To think that RFK was himself assassinated within a few months of giving this speech, it only adds poignancy to his words and highlights even more the truth and sadness of the mindless menace of violence

## The Prettiest Eyes – The Beautiful South (song)

Today I thought I would share this wonderful song by The Beautiful South – “The Prettiest Eyes”. It is from their fourth studio album Miaow, and is the fifth track on the CD. It is also on their compilation album Carry On up the Charts. The album was recorded in the spring of 1993, and released in March 1994. I don’t have any more detail about the song itself, but if someone reading this knows more feel free to add more information in the comments section below.

“The Prettiest Eyes” is a song by The Beautiful South which appears on their fourth studio album Miaow.

The song is a lovely love song, the lyrics speak for themselves.

Line one is the time
That you, you first stayed over at mine
And we drank our first bottle of wine
And we cried

Line two, we’re away
And we both, we both had nowhere to stay
Well, the bus shelter’s always OK
When you’re young

Now you’re older and I look at your face
Every wrinkle is so easy to place
And I only write them down just in case
That you die

Let’s take a look at these crow’s feet, just look
Sitting on the prettiest eyes
60 25th of Decembers
59 4th of Julys
Not through the age or the failure, children
Not through the hate or despise
Take a good look at these crow’s feet
Sitting on the prettiest eyes

Line three I forget
But I think, I think it was our first ever bet
And the horse we backed was short of a leg
Never mind

Line four in a park
And the things, the things that people do in the dark
I could hear the faintest beat of your heart
Then we did

Now you’re older and I look at your face
Every wrinkle is so easy to place
And I only write them down just in case
You should die

Lets take a look at these crow’s feet, just look
Sitting on the prettiest eyes
60 25th of Decembers
59 4th of Julys
You can’t have too many good times, children
You can’t have too many lines
Take a good look at these crow’s feet
Sitting on the prettiest eyes

Well, my eyes look like a map of the town
And my teeth are either yellow or they’re brown
But you’ll never hear the crack of a frown
When you are here
You’ll never hear the crack
Of a frown
Of a frown
Of a frown
Of a frown

Here is the official video of this lovely song. Enjoy!

## More on NASA’s Juno space probe

I have done a few interviews on the BBC in the last week about NASA’s Juno space probe; it is great to see the mission getting such press coverage. You can listen to my BBC Radio Cymru interview here, and my BBC Radio Wales interview here. With all the press coverage there have inevitably been a few misunderstandings, so I thought I would try and explain as clearly as I can what Juno hopes to accomplish and how it will do it.

Artist’s impression of the Juno spacecraft. Juno is the first space probe sent to such a large distance in the Solar System (5 AUs) to be powered entirely by its solar panels.

## Some background on Jupiter

Jupiter is by far the largest planet in the Solar System. All the other planets together would fit into it, and the Earth would fit into it over 1,300 times! Because it is the largest planet in  the Solar System, we believe that it would have dominated the formation of the planets. Once the gas in the central part of the solar nebula (the cloud of gas and dust from which the Sun and Solar System formed) had collapsed to form a nascent star, the disk of material around the still-forming Sun would have started clumping together under gravity and collisions to form the planets.

Because Jupiter is the largest planet, it sucked up most of the material in the disk of the solar nebula. It is mainly hydrogen and helium, as that is what the Sun and most of the Universe is made up of; about 75% hydrogen and 24% helium. But, the details of Jupiter’s composition are mainly based on theory rather than any hard observations.

## What are Juno’s (main) scientific goals?

According to NASA’s Juno webpage (click here to go to it), the main objectives of Juno are

• Determine how much water is in Jupiter’s atmosphere
• Look deep into Jupiter’s atmosphere to measure composition, temperature, cloud motions and other properties
• Map Jupiter’s magnetic and gravity fields, which will reveal the deep structure of the planet
• Explore and study Jupiter’s magnetosphere near the planet’s poles, especially the aurorae, and provide new insights into how the planet’s enormous magnetic field is generated and how it affects the planet’s atmosphere

I will blog about each of these four points over the next few weeks, so let me start with the determination of how much water is in Jupiter’s atmosphere.

## How much water is there in Jupiter’s atmosphere?

The reason this is an important question is that the two most popular theories for how Jupiter formed predict different amounts of water. Jupiter is thought to have either formed (i) from the collapse of a massive fragment of the Solar nebula, or (ii) from the build-up of planetesimals. In the first theory, the amount of water would be less than in the second theory, as the rocky planetesimals in the second theory would have been been coated in water-ice and ammonia-ice.

If you look at an astronomy textbook the interior model of Jupiter shows a solid core, but we have never actually observed this core.

A model of the interior of Jupiter. We believe that it has a rocky core, with a region of hydrogen under such extreme pressure that it takes on metallic properties and can conduct electricity. But, we have no direct observations of the interior.

Therefore, measuring the amount of both water and ammonia should help us decide which theory is closer to the truth. Water, ammonia, carbon dioxide and methane are examples of what we call ‘ices’ in astronomy, as in the environment of the Solar System all of these compounds can exist as gases but also as solids.

The water and ammonia will be measured by a microwave radiometer. This instrument consists of six antennae measuring the radiation at 600 MHz, 1.2, 2.4, 4.8, 9.6 and 22 GHz. These are the only microwave frequencies which are able to pass through the thick Jovian atmosphere. These radiometers will measure the abundance of water and ammonia down to a pressure of 200 bar, which corresponds to a depth below the cloud tops of 500 to 600 km. This is a small fraction of the radius of Jupiter, which is about 70,000 km, but it is still further below the cloud-tops than we have so far been able to study.

In the next blogpost on Juno, I will talk about how it will measure the gravitational and magnetic fields of Jupiter.

## The 100 best Beatles songs – number 16 – I Saw Her Standing There

At number 16 in Rolling Stone Magazine’s list of the 100 greatest Beatles songs is “I Saw Her Standing There”. This song was recorded in February 1963 and released on their debut album Please Please Me in March 1963. It is the opening track on their debut album, and was never released as a single in the Disunited Kingdom. However, in the USA it was the B-side of their debut single released by Capitol Records, with “I Want to Hold Your Hand” on the A-side. This single was The Beatles’ breakthrough in the USA, getting to number 1 in January 1964 and staying at number 1 for 7 weeks.

At number 16 in Rolling Stone Magazine’s list of the 100 greatest Beatles songs is “I Saw Her Standing There”

The song, written mainly by Paul McCartney but with some contribution from John Lennon, was written in 1962. McCartney scribbled the lyrics in a notebook from the grammar school that he had attended as a teenager.

(1,2,3,4!)

Well, she was just 17
You know what I mean
And the way she looked was way beyond compare
So how could I dance with another (Ooh)
When I saw her standing there

Well she looked at me, and I, I could see
That before too long I’d fall in love with her
She wouldn’t dance with another (Whooh)
When I saw her standing there

Well, my heart went “boom”
When I crossed that room
And I held her hand in mine…

Whoah, we danced through the night
And we held each other tight
And before too long I fell in love with her
Now I’ll never dance with another (Whooh)
Since I saw her standing there

Well, my heart went “boom”
When I crossed that room
And I held her hand in mine…

Whoah, we danced through the night
And we held each other tight
And before too long I fell in love with her
Now I’ll never dance with another (Whooh)
Since I saw her standing there

Here are The Beatles performing “I Saw Her Standing There” live. Enjoy!

## Discovery of largest solar system

This story caught my attention a few months ago, so I thought I would share it in a blogpost. I’m not sure why it has taken me so long to blog about it, but it is still a newsworthy story.

Astronomers have discovered the exoplanet (which goes by the name 2MASS J21265040−8140293) with the longest period orbit, the planet takes about 1 million years to orbit its parent star. It has been found in orbit about a red dwarf star (a star with a lower mass than the Sun), which affects the calculated size of the orbit. Based on Newton’s form of Kepler’s 3rd law, which I blogged about here, the period of orbit of a planet is given by

$T^{2}(m_{1} + m_{2}) = a^{3}$

where $T$ is the period of the orbit (expressed in Earth-years), $m_{1}$ and $m_{2}$ are the masses of the star and the planet (expressed in terms of the mass of our Sun), and $a$ is the size of the orbit, expressed in Astronomical Units (AUs). An astronomical unit is the average distance between the Earth and the Sun, and is just under 150 million kilometres.

As the parent star for this exoplanet has a lower mass than the Sun, and as the orbiting planet has a mass of about the mass of Jupiter, it has been calculated that its orbit is about 4,500 AUs! For comparison, Pluto orbits at about 40 AUs from our Sun. So, it is a truly huge orbit.

Astronomers have discovered a solar system where

You can read the submitted paper here, it was published in Monthly Notices of the Royal Astronomical Society in

Both the parent star and the exoplanet were previously observed, this discovery has been made by looking through data archives. The parent star was discovered in 2006 as part of a programme to observe associations of stars which contained young stars. The exoplanet 2MASS J21265040−8140293 was, as the name implies, observed as part of the 2MASS project, which ran from 1997 to 2001. The exoplanet was identified from the 2MASS images in 2008.

To me this piece of news shows a few things

1. That solar systems come in all shapes and sizes. This shouldn’t really be a surprise.
2. Trawling through the huge amounts of archived data we have accumulated over the last few decades can lead to exciting discoveries. As most of these archives are freely available, this means that you do not necessarily need to be working at a university with lots of telescope access to make astronomical discoveries.