Europa's Seafloor Volcanoes

SpaceTime S24E63 AI Transcript

[00:00:00] Stuart: [00:00:00] This is time series 24, episode 63, four broadcast on the 4th of June, 2021. Coming up on space time and you study suggest the Jovian ice moon Europa could have undersea, volcanoes, NASA launches, a house that you'd plasma experiment and the U S space force takes over the Vanderberg air force space, all that, and more coming up.

Um, space time.

VO Guy: [00:00:25] Welcome

to space time with

steward, Gary

Stuart: [00:00:45] You research shows volcanic activity may have occurred on the sea floor of Jupiters ice moon Europa in the recent past, and may still be happening today. Scientists have strong evidence that you Roper, harbors and enormous global [00:01:00] subsurface ocean beneath kilometers. A thick IC crossed. The new findings reported in the journal.

Geophysical research letters shows how the moon may have enough internal heat to partially melt this Rocky layer, a process that could feed volcanoes on the ocean floor. The new three dimensional computer modeling of how this internal aid is produced and transferred is the most detailed examination yet of the effect of this internal heating on the moon.

The Katy Europa's Rocky metal being hot enough to melt lies with a massive gravitational pull chip. It has on its moons as Xi robot orbits around the guests, giant huge gravitational tidal forces generated by the massive planet causes the tiny moon to literally flex stretching and compressing as it orbits this the largest planet solar system.

All this flexing generates lots of hate in the moon's interior enough, eight to melt, water ice, giving you Roper it's subsurface oceans, and maybe even enough heat to melt rocks [00:02:00] as well. The research shows where this heat dissipates and how it melts rope Rocky matter, increasing the likelihood of volcanoes on the sea floor.

Volcanic activity. Deep under Europa's icy crust has been a topic of speculation for astronomers for decades. The new studies predicted the volcanic activity. Most likely occurs knee ropers polls. The latitudes with the most hits generated. Now, if they exist, these underwater volcanoes could be pairing a hydrothermal system just like that, which feels life at the bottom of Earth's oceans on earth.

When the seawater comes into contact with hot magma at the mid-ocean ridges, the interaction results in chemical energy. And it's this chemical energy from the hydrothermal systems rather than sunlight from the surface, which helps support life, deep inner associations of volcanic activity on Europa C4 would therefore be one way to support a potential habitable environment in that moon's oceans.

Then you findings come as NASA [00:03:00] continues its preparations for its upcoming Europa clipper mission, which is targeting at 2024 launch date and a 2030 arrival time at Europa. Europa clipper will orbit Jupiter and perform dozens of flybys of Europa mapping the moon and investigating its composition among the science data.

It collects a spacecraft will survey the surface in detail and sample the moon's thin atmosphere. The surface and atmospheric observations will give scientists the chance to learn more about the moods interior ocean. If the ocean water percolates up through the icy crust. This Italian Eisman Enceladus also generates powerful guises from its south pole tiger stripes.

These eruptions are constantly spewing water, ice, and possibly salts far into space. Scientists believe the exchange of material between the ocean and the crust would leave traces of the sea water on the surface. They also believe the exchange may emit gases and possibly even plumes of water vapor with injected particles that could contain materials [00:04:00] coming from the sea floor.

As Europa clipper measures the moon's gravity and magnetic field anomalies in those areas, especially towards the polls, could help confirm the volcanic activity predicted by the new research search. This is space-time still the com NASA launches, a high-altitude plasma experiment, and the Vandenberg air force base gets a new name.

All that is more sort of calm. Um, space time.

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VO Guy: [00:06:35] This is space time

Stuart: [00:06:37] with Stuart. Gary NASA has launched a signing rocket on a mission to better understand the interaction between charged particles from the sun and those in near-Earth space.

The four stage black brand 12 suborbital flight was launched from NASA Wallops island flight facility on the Virginia Mid-Atlantic coast, flying on a broad arc into the artist's fear over the Atlantic ocean, and then [00:07:00] descending me Bermuda. The mission came on the final day of a 10 day launch window, which had been plagued by bad weather and high altitude wins.

The mission payload was the university of Alaska Fairbanks, kinetic scale energy momentum, transport experiment. It's designed to study how plasma, energy and momentum, uh, transported between different regions of space, which are magnetically connected. Principal investigator paid a Della Mae says the Aurora Australis and Aurora Borealis Southern and Northern lights are formed with ionized particles from the sun flowing in the solar wind and coronal mass ejections are captured by Earth's magnetosphere and transported down magnetic field lines at earth atmosphere, where they collide with atoms and molecules, releasing photons and putting on their spectacular light displays.

Telomere. He says that electrons in earth, local space environment out of the solar wind have relatively low energies, but the Aurora, uh, generated by very high energy electrons. And he wants [00:08:00] to understand this energization mechanism. Another example of energy momentum transport is interaction between Iowa's atmosphere and Jupiter's local space environment, which leads to an Aon juiced auroral spotting Jupiter's atmosphere.

Let's turn on, know the power generated by iOS interaction and the auroral power from the spot, but they don't know how the energy and momentum is transported along the connecting magnetic field lines between the two to try to work this out, the kinetics experiments. So the how that you'd release of two candidates, there's a barium thermite producing purple green plasma clouds.

These plasma clouds then generated their own electromagnetic fields and waves, which then interacted with the existing plasma in its ionosphere. This space-time still to come. The Vandenberg air force base gets a new name and the June solstice, the constellation Virgo and the towards media or shower among the highlights of the June night skies on sky.

Watch [00:09:00] all that and much more still to come. On space time.

The Vandenberg air force base in California has been renamed the Vandenberg space for space. The name change took place at a special salmon in the parade grounds of the sprawling facility. 230 kilometers north of Los Angeles. Vanderburg is used for ballistic missile and orbital rocket launches, and was also being equipped to launch space shuttles from the west coast.

It's geographical location made it ideal for launches into polar orbits. Vanderburg's hosted at the 30th space wing has been renamed space, launched Delta under the new space operations command. The United States space force was created the sixth uniform military branch in [00:10:00] 2019 by us president Donald Trump personnel, formally assigned to the air force space command have been reassigned to the space force.

Vanderberg was originally established back in 1941 during the second world war as camp cook a us army Garrison for tank infantry and artillery training. This is space time.

And Tom had to check out the night skies of June on sky. Watch. June is the fourth month of the old Roman calendar. And he's named after Juno. It was the wife of Jupiter and also the equivalent to the Greek goddess. Hara. Another belief is that the month name actually comes from the Latin word. You , which means younger ones, cheer in is a great time to look up at the night skies and Marvel at the [00:11:00] majesty of the Milky way, which puts on a spectacular display this time of year.

And of course, June also max, the June solstice. Which this year happens at 1330, two Australian Eastern standard time on the afternoon of Monday, June the 21st. That's 2332 on the night of Sunday, June the 20th, us Eastern daylight time at three 32 in the morning, June the 21st Greenwich meantime here in the Southern hemisphere.

It's the time of the winter solstice. Of course it means the arrival of summer for our lucky listeners north of the equator. The June solstice occurs when the sun reaches its most northerly point in the sky as seen from earth Zenith appearing to be directly over the Tropic of cancer, contrary to popular belief that the seasons on earth occur when the earth orbit around the sun is at its nearest or furthest points.

They're actually governed by the tilt of earth axis as a journeys around the sun in a year. So on the day of the June solstice, the earth south pole [00:12:00] is tilted by 23 and a half degrees away from the sun. The sun rises north of east and sets north of west six months later when the south pole is tilted towards the sun, it's the Southern hemisphere summer.

And in between we have the autumn and spring equinoxes almost overhead. This time of year, we have the constellation Virgo. The constellations named after Virgo, the goddess of justice and the harvest in ancient Greek mythology. They used her scales to weigh good and evil. However, she became SODIS and chatted with the evil deeds of men.

He threw away his scales and retreated to the heavens. Interestingly, the ancient Egyptians also associated Virgo with agriculture there. She was the goddess ISIS who sprinkled the heads of wheat across the sky, forming the Milky way. To science. Virgo is a tightly packed region of space containing some 2000 galaxies, all gravitationally bound into a gigantic galaxy cluster located some 60 million light years away [00:13:00] of which our local group of galaxies simply an outlying member, a light year is 10 trillion kilometers that distance of photon can travel in a year at the speed of light, which is about 300,000 kilometers per second in a vacuum.

And the ultimate speed limit of the universe. The mass of the Virgo supercluster is so enormous that it's gravity generates the circled Virgo centric flow causing our Milky way galaxy as well as Andromeda and all the other members of our local group to move towards the supercluster at around 400 kilometers per second.

That's despite the accelerated expansion of the universe over cosmic timescales. The Virgo superclusters now thought to be nothing more than a lobe of an even bigger galaxy supercluster known as Lenea care. The center of which is known as the great attractor Lanny, a K, and the great attractor are among the largest known structures in the universe.

Despite the Virgo cluster size it's so far away, it's difficult to see without a [00:14:00] decent size backyard. Telescope you'll want something at least a hundred millimeters in diameter or larger. Located right next to Virgo and directly overhead. This time of year is the constellation Corvus. The Crow Greek mythology tells us Corvus could talk to humans, but he was a lazy bird.

And so Apollo took away his ability to speak and banished him to the heavens. One of the highlights in the constellations, Virgo and Corvus is the spectacular sombrero galaxy M one oh four. Visible with a good pair of binoculars or a small telescope. This stunning spiral galaxy is seen almost edge on providing a spectacular backlit view of its galactic, bold stars and the molecular gas and dust lanes in its arms.

And one of four is located some 31 million light years away and he's moving away from the Milky way at about a thousand kilometers per second. The sombrero galaxy is the diameter of about 50,000 light years. That's about 30% the size of our own [00:15:00] galaxy. The Milky way. It's surrounded by up to 2000 globular clusters and an active central supermassive black hole, at least a billion times, the mass of our sun by comparison Sagittarius, a star that's the supermassive black hole at the center of the Milky way has just 4.3 million times the mass of the sun.

Well, I'll be like Costas, a tight balls containing millions of stars, which were all either originally formed at the same time, from the same collapsing, molecular gas and dust cloud, or they're the surviving cause of small galaxies that have been cannibalized by larger ones. By the way, the brightest star in Virgo is spiker a spectroscopic binary located some 250 light years away.

Spectroscopic. Binary's a double star systems Albany, so close to each other, or at such an angle that they can't be visually separated. At least not from our viewpoint on earth. Under these conditions. Their spectrum will actually be a combination of the spectrum of both of the [00:16:00] stars in the system. But as the stars orbit each other, one of the stars will be moving sort of towards us.

The other will be moving sort of away from us. So the star moving towards us, we'll have a spectra that will be slightly blue shifted in the high frequencies, showed a wavelength. Well, the star moving away from us. Well, I've it spectra slightly red shifted to lower frequencies, longer wavelengths. And so the two stars in the system can be separated by their Doppler shift.

Looking about 20 degrees above the Western horizon in the early evening is the fourth brightest celestial object in the sky. The dog star Sirius. Early the sun, the moon and the planet Venus look brighter to the Northwest or right of Sirius is another fairly bright star called Prosci on the brightest star.

The constellation canis minor, the lesser dog in Greek mythology, canis, minor, and Candice major where ARIDES hunting dogs, press yawn [00:17:00] is a binary star system comprising a spectral type F main sequence, white star pro CNA, and a faint white Wolf companion. Press Yon bay main sequence stars are those undergoing hydrogen fusion into helium in there because Australia's described stars in terms of special types, a classification system based on temperature and characteristics.

The hottest most massive and most luminous stars and spectrum type old blue stars. They're followed by spectral type B blue white stars, inspector type, a white stars, special type F whitish yellow stars, spectral type G yellow stars. That's where our son fits in spectrum type K orange stars. And then the coolest and least massive of all stars are spectrum type M red stars humbly referred to as red dwarfs.

Each spectral classification is also subdivided using a numeric digit to represent temperature with zero being the hardest and nine, the coolest and a Roman [00:18:00] numeral to represent luminosity out, put all that together. And our son is officially classified as a G2 veal, G2 five yellow dwarf star. Also included in the classification system, a spectrum types, LT, and Y, which are assigned to failed stars, known as brown dwarves.

Some of which are actually born as spectra type in red Wolf stars, but became brown dwarves after losing enough of their mass. Brown dwarves fit into a category between the largest planets, which are about 13 times the mass of Jupiter and the smallest spectral type Embridge Wolf stars, which are around 75 to 80 times, the massive Jupiter or 0.08, solar masses.

The white dwarf Prosi on B has about 0.6 times the mass of the sun, and a diameter of about 8,600 kilometers. A white dwarf is the stellar corpse of a sun-like star. Haven't used up its nuclear fuel supply, fusing hydrogen into helium, and the main [00:19:00] sequence. It then expands. It will red giant and begins fusing helium into carbon and oxygen stars.

Like our sun. Aren't massive enough to fuse carbon and oxygen into heavier elements. And so they turn off their outer gaseous envelopes, float off into space as spectacular objects called planetary Nebula. What's left behind is a super dense white heart. Still a core about the size of the earth called a white dwarf, which will slowly cool over the eons of time located about 11.6 light years away, press you on a is about one and a half times the mass of the sun at about twice its radius.

It also has about seven times the sun's luminosity making it unusually bright for a star of this type. And that suggests that it started to evolve off the main sequence after having fused nearly all of its core hydrogen into helium. It means the Star's about to expand into a sub giant as it begins, fusing core helium into carbon and [00:20:00] oxygen and burning a hydrogen and its outer shell.

As it continues to expand, the star will eventually swell to somewhere between 80 and 150 times its current diameter it'll then become a red giant. This'll probably happen within the next 10 to 100 million years. The blink of an eye in astronomical terms, the two stars per se, on a and B orbit each other, every 40.82 earth years at an average distance of 15 astronomical units about the distance of Uranus's orbit around the sun and astronomical unit is the average distance between the earth and the sun, which is about 150 million kilometers or 8.3 light minutes.

Looking to the north Northwest now. And you'll see the constellation, Leo, the lion looking like a bunch of stars shaped like an upside down question, mark located just 36.7 light years away in the constellation booties. The herdsman is Arcturus a bloated aging red giant [00:21:00] about 7.1 billion years old and nearing the end of its life.

Having used that bullet's core hydrogen it's now fusing helium into carbon and oxygen. That's caused that star, which is only slightly more massive than the sun to expand outwards to around 25 times the suns diameter and become about 170 times as luminous it'll soon puff off its outer gaseous envelope is a planetary Nebula in the process revealing its white hot stellar core in Greek mythology.

Arcturus was the guardian of the bear. Now this is a reference to being next to the constellations, Ursa major Ursa, minor, the greater and lesser bears. There's some indications that actors could have a binary star companion, but the results remaining conclusive, at least for now, there's also speculation that it could have a large planet or sub stellar object orbiting it something about 12 Jupiter masses in size.

But again, the research remains inconclusive looking to the [00:22:00] east and you see the three brightest stars in the constellation of Libra at the scales of justice, visible about half way at 40 degrees above the horizon. These also represent the cause of scope is the scorpion, which is chasing a Ryan across the sky.

The brightest star in the constellation Scorpius is alpha Scorpio or Antares. Scorpion's heart easily. Seeing with the unaided eye, this red super giant is some 550 light years away. And it's one of the largest known stars in the universe. And terrorists has about 18 times the mass and an incredible 883 times that I am at her with the sun.

And it's about 10,000 times more luminous than our son too. Okay. Turn into the south east now, and then you'll see the constellation such a terrace. The Archer it's important is it marks the direction to the center of our galaxy, the Milky way. And of course located some 27,000 light is a way in that direction is the galaxy central supermassive black hole Sagittarius, a [00:23:00] star.

To the ancient Babylonians said your terrace was the God nerve all the center, a creature half man and half horse by the time Greek mythology took over Sagittarius was carrying a bow loader with an arrow and pointing directly towards Antares for heart of Scorpius the scorpion, the center of the Milky way.

And it's super massive black hole Sagittarius, a star light in the Western most part of Sagittarius. The brightest star in Sagittarius is Epsilon search at Terri or cause Australia's the Southern part of the Bo Epsilon surger. Terry's a binary system located at 143 light years away. The primary star is an evolved spectral type II blue giant at the end of its life on the main sequence, it has about three and a half times the sun's mass and about seven times its radius and is radiating around 363 times the sun's luminosity.

It's also a very strong x-ray source and he's spinning very rapidly with an estimated radio velocity of some [00:24:00] 236 kilometers per second. The system also displays an Xs of infrared radiation emissions, suggesting the presence of a circumstellar disc of dust. Now at the second star in the system appears to be inside of this debris disc astronomers.

Think it's a spectra type G yellow dwarf star with about 95%, the mass of the sun. The second brightest star in Sagittarius is Sigma Sagittarius, or non-key the name though? He's Babylonian. However its meanings are unknown. It's thought to represent the ancient Babylonian sacred city of Urdu on the Euphrates river, uh, F correct.

They would make non-key the oldest known Stein aiming current use non-key is a spectral type eat blue star located about 260 light years away. It has about eight times the sun's mass four and a half times its radius. And about 3,300 times the sun's luminosity alpha, such a Cheerio rock bat, meaning the arches ne is a spectral type B BlueStar [00:25:00] located some 182 light years away.

It has some two and a half times the diameter of the sun at about 40 times. The sun's luminosity. Astronomy think it's surrounded by a dense debris disc and a new born companion star, which is only now about the join, the main sequence, the Sagittarius constellation also hosts many star clusters Nebula, including some of the best known astronomical objects in the sky.

These included the lagoon, Nebula messier aid, a spectacular pink emission Nebula ACAD is 5,000 light years away and measuring some 140 light years by 60 light years across. The central region of the lagoon. Nebula is also known as the hourglass Nebula because of its distinctive shape caused by a, at propelled, by a massive staff warming region called Herschel 36.

One of the few staff forming Nebula that it's possible to see with the unaided eye, the lagoon Nebula was instrumental in the discovery of Bach globules. Well, then 17,000 of [00:26:00] which have been found in the Nebula. Astronomers think Bach globules contain embryonic predator stars destined to eventually become you.

Stellar generations also located in this region of space. Is the stunning messier 17, better known it pretty well. Everyone is the Horsehead Nebula. It's located at some 4,890 light years away and is a dense region of ionized, atomic hydrogen. Also known as the Amigos Swan Nebula, it spans some 15 light is a cross and has about 800 times the mass of the sun.

It's considered one of the brightest, the most massive stuff, forming regions in our galaxy with a geometry, similar to the Ryan Nebula, except that it's been viewed edge on rather than face on. European star cluster NGC 66, 18 lies embedded in the nebulosity and it scatters caused the Nebula to shine due to the intense radiation from its hot young stars.

Open star clusters, loosely bound groups of stars usually [00:27:00] containing a few hundred to thousands. They're thought to originally all been formed in the same molecular gas and dust cloud, but they're not as densely bound together as globular clusters. I've been star clusters generally survive for a few hundred million years with the most massive ones, maybe surviving for a few billion at by contrast, the more massive globular clusters exerts, such a strong gravitational attraction on their members.

They can survive for tens of billions of years or longer. The nebulous thought to contain up to 800 stars more than a thousand additional stars are also being formed in the surrounding molecular gas and dust clouds. It's also one of the youngest known classes with an age of just a million years, the cloud of interstellar material, which formed the Nebula is roughly 40 light years in diameter.

And it contains at least 30,000 solar masses. The Triffid Nebula messier 20 is another large staff forming a mission Nebula containing many young heart stars. Okay. Between 2000 [00:28:00] and 9,000 light years away, the Triffid Nebula is a diameter of around 50 light years. The outside of the Triffid is a bluish reflection Nebula or the inner region glows pink.

Thanks to ionized hydrogen. There are also two dark bands dividing the Triffid Nebula into three regions or lobes hydrogen in the nebulous being ionized by a central triple star system, which formed at the intersection of the two dark bands, creating its characteristic pink color. Another staff for me region in this part of the sky is NGC six, five, five, nine, like edit some 5,000 light years away.

Again, tanning, both red emission and blue reflection regions. Now the gripping of these three Nebula that the guru Nebula, the Triffid Nebula and  is known as the Sagittarius triplet. Another object worth looking out for is the red spider Nebula, NGC six, five 37. It's a planetary Nebula, [00:29:00] about 8,000 light years away.

It has a prominent to lobe shape. It could be G2, a binary companion, or simply magnetic fields. And it has a fascinating shaped symmetry with the lobes opposite each other, appearing similar. Again, this is believed to be due to the presence of a companion star to the central white dwarf. As for the central white dwarf, the remnant of the original star, it produces a powerful 10,000 degree hot 3000 kilometer per second, stellar wind, which is generating 100 billion kilometer high waves from supersonic sharks formed as the local gas is being compressed and heated in front of the rapidly expanding lobes.

Adam's caught up in the sharks, a radiating invisible light, giving the Nebula its unique spider like shape and also contributing to the nebulous expansion. The star at the center of the red spot, a Nebula is surrounded by a dust chill, making its exact properties hard to determine its surfaced.

Temperature is probably somewhere [00:30:00] around 250,000 degrees. Although a temperature of up to half a million degrees can't be ruled out, which would make it among the hottest white dwarf stars known. Yeah, looking directly south right now. You'll see the star Polaris Australia's or more accurately Sigma rock tatters.

It's the nearest star to the Southern celestial pole and consequently, the counterpart to the Northern star Polaris, however Sigma or tat is, is far harder to see them. Polaris is it's much fainter located some 270 light years away. It's an orange giant Regina, the end of its life. Yeah, turning to the Southwest and just above the horizon, you'll see the star.

Canopius it's the second brightest star in the night sky. After serious cannabis is located some 310 light is away. And is the brightest star, the constellation Korean or the keel Canopius is a super giant. So nine times the mass of the sun and 71 times its diameter. The month of June also marks the first of two [00:31:00] annual encounters with a towards media or shower.

The guides are generated as the earth passes through the debris stream created by the comment TUPE inky, which itself could be part of a larger comment, which broke apart about 20,000 to 30,000 years ago. Most likely following numerous interactions with the powerful gravitational field of the planet.

Jupiter as their name suggests the towards radiant or apparent point of origin is in the constellation. Tourists. The ball towards media was shower is made up of large kibble, massive material. Think of pebbles instead of dusk rains earth passes through this stream twice every year, once in June, then again in October where it's called the Halloween fireballs, the tour it's releases material birth by normal cometary activity.

And also occasionally by close encounters with a tidal gravitational force of the earth and other planets. Now all this combines to make the Torrid stream of material, the largest in the inner solar system. [00:32:00] And since the meteor stream is rather spread out in space. Yes. We'll take several weeks to pass through it causing an extended period of media activity compared with a much smaller periods of activity for other media showers now included in the tourist stream is a denser flow of gravelly.

Meteoroids called the Torrid swarm. It's thought to be a ribbon of rocks, roughly 75 million kilometers wide by 150 kilometers across and held in-orbit budgeted as gravity. Yeah, occasionally the earth will pass through some of the larger meteoroids in the denser towards swarm, and that can make things rather interesting on earth.

In fact, one of the larger chunks of the tourist swarm is now thought to have been the cause of the infamous tango SCA meteor event. The skies of a Siberia on June the 30th, 1908. The town goose girl event is now believed to have been the airburst of a 100 meter wide meteor over the dag Glusker region of Russia causing mass devastation and flattening more than 2000 square [00:33:00] kilometers of forest in the matchsticks.

In fact, the blast was so bright. It lit up the skies in London. Third of the way around the planet. 10 Gasca remains the largest known earth impact event in recorded history. It was considered a one in a thousand year event, assuming a random distribution of events over time. But new study suggests the event may have been caused by a toured swore medial and with earth passing through the swarm periodically.

It changes the OD significantly. Now, if this study is correct, the swarm heightens the possibility of a cluster of large impacts on earth over a relatively short period of time for the complicating matters. The gene towards are actually seen as two separate showers. The Southern tourists are the ones associated with the comet TUPE inky while the Northern tourists originate from the asteroid 2004, TG 10 and eccentric kilometer wide asteroid classified as an era object and a potentially hazardous asteroid of the Apollo group.

[00:34:00] Jonathan Nalli, he's the editor of Australian sky and telescope magazine. And he joins us now to continue our tour of the June night skies.

Jonathan: [00:34:09] So you have a second look, the nights go up in June for us in the Southern hemisphere, which is withdrawn. If we're heading, heading into winter over in way to now.

Sorry, this the interesting thing actually about that season. So in Australia here, we can see that window to be just three calendar months, June, July, and August. Whereas in some other parts of the world, this season will start exactly on the solstice.

Stuart: [00:34:34] That's most countries, isn't it do that? Well, we're unusual where this is a British sort of thing to not use it

Jonathan: [00:34:39] sort of thing, but look, most, most seasons sort of, um, not really correspond with the seasons. Um, I mean, talking about winter and summer to someone who lives

Stuart: [00:34:47] in the tropics I used to live in

that's right. So anyway,

Jonathan: [00:34:54] um, winter time, basically here in the Southern hemisphere where I am in summertime. North summertime of course is great for [00:35:00] viewing because you go out and position stargazing and it's nice and warm. And the weather is usually go wait a time. And it's called, uh, the one advantage you get with windows that the nights are longer.

So you do have more time of darkness, as you said, if it's. Cloudy at seven o'clock at night, you know, leave it till nine and thousand more to clear it up. So that is the one advantage I've been doing. Some start gagging during winter puddle cycle. She can see what to good things are in June, which you go outside and you have a look, you'll see our galaxy scene from the inside, which the Milky white stretching all across the sky from the east to west, that's been sort of early part of the evening after it's got dark for us down here in the south, to be able to say the Southern cross.

Yeah, two thirds of the way up from the Southern horizon and the upright, it looks a bit like a kite, pretty easy to see these four stars raise will be bright. So it's very small constellation. So people go out and they think it might be a huge thing, but it's actually smallest constellation. There is though.

Don't look for something that's really giant. It's really compact, like a little, little kite flying in the sky over in the west about to disappear for the rest of the season is the brightest star, the notch by serious and the [00:36:00] constellation kind of major and wrapped around what's lift or Southwest. Yes.

The second brightest star in the sky called Canopius that's in the constellation called Corina. If you're in a dark location and you're down here in the south, you've got clear SCADA and unobstructed view of the Southern horizon. Have a look and see if you can spot these two Magellanic clouds. We're always going on about, this is a good time to say them.

They're very fine. They just look like little faint, fuzzy clouds, but they are actually fairly sizeable galaxies. There's a named off to the Explorer, Ferdinand, Magellan, who spotted them as he was sailing around the world. You need to have dark guys. You can't see them if you're standing under a straight lot or something.

So. If you get somebody, a doc and let your eyes adapt to the darkness, that you can see faint things and look down the south and see if you can see these couple of smudges that you've got the large one and the small one, they're a little distance apart, but once you spoke them, you'll always be able to spot them.

Then once you recognize what they look like, And every time you go out and you've got some docs scholars, you should be able to say them, if they're up at that time of the year, uh, the Northern half of the sky for us down the south, this time of year Northern half of this class, seems a bit bare. A lot of the good stuff that can be saying [00:37:00] in the Northern hemisphere.

We can't see from down here, we can see the Brightstar Arcturus, which is about halfway up from the Northern horizon or the head roughly from the attitude of Sydney and cities of that latitude by you can see another Brightstar called spiker. Now Arcturus. It's a red giant star. It's a couple of bit in, he is older than half sign, about two and a half billion years older than that son.

It's the same mess as our son, but it's all older and it's ballooned up to be about 25 times bigger than half son. And that starts to become absolutely huge compared to a good old soul. The other star, I mentioned spiker. That's interesting too. It's a binary star system. Who's two stars, a pair of stars, orbit so close to each other, and it takes four days for them to orbit around each other that there, their mutual gravitational pull is so strong because they're so close.

Each of them has been stretched into an egg shape. Robin being around style. So I imagined that an enormous. One of them is big. One of them small and enormous star talking, actually that egg shaped, not just a flattened sphere, I'm actually talking egg. So, so [00:38:00] one side of it is pulled out and pointing in the direction of the other star.

And the other star is pointing in the direction of that stuff.

Stuart: [00:38:05] So the prime attentional attractions

Jonathan: [00:38:07] really strong passionately attraction is very cause they're so close to each other. They orbit around each other every four days. Can you imagine a huge star doing that? So it really interesting when you go out and look at some of these stars, when you know what you're looking at, when you do a bit of investigation and work out what scientists.

I found that I take on a bit more interesting things than just digital. Lots of light in the sky. Okay. So that's what you see in the, throughout the evening between sunset and midnight, the night goes on though. You'll see that things change and that's because the earth is spinning on the text. So different styles are coming up in the east and other stars are going down the west.

So by midnight, Sirius has gone in the west and you got the bright stars, Vega, and the Altec have appeared in the north. Pretty low down far in the north for people in the Southern hemisphere, but they're still good to look at way down south. We have another broad stuff or economic that's, um, that one economic and the sort of Southern cross and Canopius they formed this big triangle on the sky.

So it's pretty easy to [00:39:00] spot economic and the Milky way, which was stretching east to west across the sky in the early. And he now stretching north to south. So it hasn't moved. You, if it's turning on its axis, that's moving and our viewpoint is therefore changing. So let's look at the planets. So we'll start with mercury, the innermost planet.

First half of June, forget it. It's lost in this Twilight, the glare of the sun in the west and the sun's going down. But in the second half of June, it will pop up the other side of the sky over the Eastern horizon just before sunrise. And it should be fairly easy to spot. If you have a clear view of the horizon.

Metric just looks like a stock. It doesn't look like much. Even if you get a total skin up onto it. If you get a big telescope onto it, it looks a bit like the moon, but I wouldn't go pointing a telescope anywhere near the Eastern horizon. When the sun's about to come up just in case you blind yourself.

So please don't do that. The other in a planet Venus. Well, that's pretty easy to see actually, and that is above the Western horizon just after sunset. So when the sun goes down, look at the wish, see a big, bright star looking thing. That'll be Venus. And as each day goes by throughout the month, you'll see it climbing higher and higher in the sky each day.

It's just a little bit harder to get [00:40:00] hot, a little bit higher on the 12th. If you've got a clear score on the 12th, go ahead and you'll see that really, really thin Crescent moon just to Venus. Right? So that's your look, pretty speaking. You've got this bright. Styling things, Venus and really, really slender in credit.

Right? So that looks should look nice by the end of the month. If you keep an eye on Venus and much of the sky that gets higher and higher, you'll see it drawing closer to a reddish looking star. That's a bit higher up in the sky. Well, that's not a star, that's actually the planet Mars. So they're going to be reasonably close together.

I mean, not exactly side by side, but in the same part of the sky miles across. The whole flotilla of space craft on it at present or the circling in orbit above or,

Stuart: [00:40:42] yeah, that's

Jonathan: [00:40:43] another thing I like to think of when I look at these planets, I think, oh, there's a spacecraft they're doing this and that. And then it's even caught, it sent these little machines all the way there and they're working and they're sending back pictures and it's just absolutely marvelous.

Now I have a pair of binoculars, take a look on June 24th and 25th. Well, if you've got a, what they call a small wide field [00:41:00] telescope, which gives you a wide view and use that as well, but pair of binoculars or do I would look at Mars on June 24th and 25th. And you'll see behind Mars in the distance. Well, it's, it's it's right in the distance.

There's a stock class tomorrow is going to go right in front of the stock cluster. It's called the Beyhive cluster or Missy up a 44. And it should be an absolutely wonderful sight to see this red planet. With these beautiful spots when he stopped behind us, it really should look nice. So he didn't get a chance June 24th, 25th.

Now, if you want to see Jupiter and Saturn, you're going to have to stop. Get lighter. Seven comes up over the Eastern horizon, about 9:45 PM, beginning of June with Jupiter, about an hour and a quarter later, if you have a look on June the 28th, you'll see the moon right next to the seventh. And the following night, mum will have moved and it'll be right next to Jupiter.

This is a really easy way actually, to identify planets, if you don't know which planets out there, if you know, coming up that the moon as it trundles around its orbit and shifts from night to night, if you know that the moon is going to be next to one of these planets or near to one of these planets, you can go out on that night and to say, okay, there's [00:42:00] the moon.

So the nearest, bright thing to the moon must be stupid or satin or whatever. So just give that a state again, June 28th, go out and have a look for the moon. And they brought a thing near the moon will be settled. And the next month, June 29th, the brightest thing near the moon will be Jupiter. Definitely, really can't mystery, but it goes to these really, really bright, uh, what else we've got, we've only got one more thing to talk about for this month.

And that is this month, June 21st, we reached the solstice of course,

Stuart: [00:42:22] winter solstice for us in the Southern hemisphere.

Jonathan: [00:42:27] That's right. So on this day, the hours of darkness are longest in the Southern half of the planet and the hours of daylight of longest in the Northern part of the planet. So some up

Stuart: [00:42:36] there, down here, The editor of sky telescope magazine.

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