This is Spacetime Series twenty six, Episode fifty four, for broadcast on the fifth of May twenty twenty three. Coming up on Spacetime, changing our view of the nature of dark matter, Europe's Integral Spacecraft, Safer Last and Rocket Labs, New Electrons Sounding Rocket, All that and more coming up on Spacetime. Welcome to Spacetime with Stewart Garry. A new study claims that ultra lightweight particles based on the hypothetical Axeon acting in waves could provide the answer to the
long standing mystery of dark matter. It's a disturbing fact that most of the matter in the universe, amounting to his staggering eighty five percent by mass, cannot be observed and consists of particles not accounted for by the standard model of particle physics, the foundation stone upon which science is understanding of the universe is based. What that means is that everything we see in the universe, from the largest galaxies and stars, through the planet's asteroids, moons, right down
to the Earth. People, houses, cars, trees, dogs and cats make up only fifteen percent of the total mass of the universe. And for a scientist that's really disturbing. As For the other eighty five percent, scientists refer to it as dark matter they not exist because they can see it's gravitational influence on the things we can see. Without dark matter, galaxies would fling apart as they rotate. But as to what dark matter is or that's the
mystery for us, it's invisible mysteries as something scientists like to solve. So finding the particle that makes up dark matter is an urgent problem in modern physics. Not only would it solve many problems in our current understanding of the universe, but it would also provide a glimpse into a realm of new physics beyond
the standard model, and that is intriguing. While some theoretical models proposed the existence of ultra massive subatomic particles as a possible candidate for dark matter, others suggest ultra lightweight particles. Now, a report in the journal Nature Astronomy has provided the most direct evidence yet that dark matter does not constitute ultra massive particles, but instead comprises particles so light that they travel through space in waves.
If correct, this work could resolve an outstanding problem in astrophysics first race two decades ago. Problem was why do models that adopt ultra massive dark matter particles failed to correctly predict the observational position and brightnesses of multiple images of the same galaxy created through gravitational lensing. We know dark matter does not emit, absorb, or reflect light, which makes it difficult to observe using traditional astronomical techniques.
Today, the most powerful tool sitists have for stating dark matter is through gravitational lensing. The phenomenon first predicted by Albert Einstein in this theory of general relativity. Now, in this theory, mass causes space time to curve, and that creates the appearance that light bends around massive objects such as stars, galaxies, or groups of galaxies. Now that bending light acts like a lens,
allowing you to see clearly more distant objects. It's an important astronomical tool, and conversely, by observing this bending of light, astronomers can infer the
presence and distribution of dark matter. Now in gravitational lensing, when the foreground lensing object and the background lensed object, both constituting individual galaxies, are closely aligned, modible images of the same background an object can be seen in the sky, but the positions and brightnesses of the multiply lensed images all depends on the distribution of dark matter in the four ground lensing object, thus providing a
especially powerful probe of dark matter. Back in the nineteen seventies, hypothetical particles referred to as weakly interacting massive particles or whimps were proposed as the most likely candidates for dark matter. Now, the whimps were thought to be ultra massive that is, more than at least ten times as massive as a proton,
that they interact only with matter through the week nuclear force. The particles emerged from supersymmetry theories, which would developed to fill deficiencies in the standard model. However, over the past two decades, adapting ultra massive particles for dark matter have left astrophysicists struggling to correctly reproduce the positions and brightnesses of multi lensed images.
In these studies, the density of dark matter is assumed to decrease smoothly outwards from the centers of galaxi, in accordance with theoretical simulations employing ultra massive particles beginning also in the nineteen seventies, but in dramatic contrast to whimps, versions of theories that seek to rectified efficiencies in the Standard model, or those such a string theory, which seek to unify the four fundamental forces of nature,
meaning the three in the Standard model. These strong and weak nuclear forces and the electromagnetic force, along with gravity, have been advocating the existence of ultra light particles referred to as axions. These hypothetical particles are predicted to be far less massive than even the lightest particles in the Standard Model, and therefore
constitute an alternative candidate to dark matter. Now, according to the theory of quantum mechanics, ultra light particles travel through space in waves, interfering with each other in such large numbers as to create random fluctuations in density. These random density fluctuations in dark matter give rise to well, I guess you call them
crinkles in space time for the dark matter surrounding galaxies. Now, you'd expect that different patterns of spacetime around galaxies depending on whether dark matter constitute ultra massive or ultra light particles, in other words, smooth or wrinkly, or to give rise to different positions and brightnesses for moudibly lensed objects of background galaxies.
The new work led by Alfred Amrit from the University of Hong Kong. It's calculated how gravitationally lensed images generated by galaxies incorporating ultra light dark matter particles would
differ from those incorporating ultra massive dark matter particles. Their research has shown that the journal level of disagreement found between the observed and predicted positions, as well as the brightnesses of mudibly lensed images generated by models incorporating ultra massive dark matter, can be resolved if you simply adapt models incorporating ultra light dark matter particles. And they also show that models incorporating ultra light dark matter particles can reproduce
the observed positions and brightnesses of multiply lensed galaxy images. Now, this is an important achievement, revealing the crinkly rather than smooth nature of space time around galaxies. The possibility that dark matter does not comprise ultra massive particles also alleviates other problems in both laboratory experiments and astronomical observations. You see, laboratory experience have been unsuccessful in finding whimsy, long favored candidate for dark matter. These
experiments are now in their final stretch. They'll culminate with the plan down experiment, and that will leave whimps with no place to hide if they're not found. Also, if dark matter comprises ultra massive particles, then according to cosmological simulations, there should be hundreds of satellite galaxies surrounding our Milky Way galaxy. However, despite intensive searches, only fifty or so satellite galaxies have ever been
discovered around the Milky Way. On the other hand, if dark matter comprised ultra light particles instead, then the theory of quantum mechanics predicts that galaxies below a certain mass simply can't form owing to the wave interference of these particles, which would explain why there is a few said light galaxies around the Milky Way.
The studies authors say that incorporating ultra light rather than ultra massive particles for dark matter resolves several long outstanding problems simultaneously, both in particle physics and in astrophysics. It's an interesting and fascinating prospect this spacetime still to come. The European Space Agency's Intrial Spacecraft now Safe and Rocket Labs developed a new version of the Electron rocket, especially for use in hypersonic experiments or that and more is
still to come on spacetime. The European Space ages is Integral spacecraft is safe
at last, following an extended series of fixes developed by mission managers. The Integral Space Observatory was designed to study some of the universe's most energetic events, things like gamma ray bursts, black holes, and supernovae, but in twenty twenty, the probe's thrusters suddenly failed that to keep the mission alive, these has developed a new series of specialized maneuvers to continue flying the spacecraft using only
its reaction wheels. These are rotating gyrodigms inside the satellite that allow it to store and use angular momentum to change its orientation. However, the spacecraft's original safe mode system, which activates the switch off scientific instruments and rotate the spacecraft so that its solar arrays always faced the Sun, relied on the thrusters to
spin the spacecraft safely in the event of an emergency. The safe mode it was triggered a year later when the charge particles struck a sensitive part of intricles electronics, disabling one of its reaction wheels and causing the spacecraft to spin away from the Sun. Mission managers were able to override the issue and rescue the
spacecraft, but it's left the probe without a safe mode. So now Integal's team have developed a new workaround in which newly uploaded algorithms determine the best way for the reaction wheels to operate in order to maneuver the spacecraft during safe mode. This is spacetime still to come rocket Lab's new Electron signing rocket variation, and we explore the Constellation Scorpio, the spectacular M six and M seven open
star clusters, and the Etta Akwood's meteor shower produced by Halley's Comet. In the May edition of SkyWatch, Rocket Labs developed a modified version of its highly
successful Electron orbital launch vehicle specifically designed for suborbital hypersonic test flights. Companies been selected to provide hypersonic launch services under a Multi Service Advanced Capability Test Bed or MACTB project, which was awarded by the United States Naval Surface Warfare Center on behalf of the US Department of Defense and the Defense Innovation Units Hypersonic and High
Cadence Testing Capabilities or HIGHCAT program. The you modified version of the Electron to be called the HASTE, or Hypersonic Accelerated Suborbital Test Electron, were launched from the company's new Wallops Island Flight Facility complex on the Virginian mid Atlantic Coast. HASTE uses the same carbon composite structure and three D printed Rutherford engines as the electron, but with a modified kickstage for hypersonic payload deployment, a larger seven
hundred kilogram payload capacity, and custom payload fairings to accommodate larger platforms. This space, time and time matter. Turn our eyes to the skies and check out the celestious sphere for the month of May on SkyWatch. May is the fifth month of the year in both the Julian and Grigorian calendars. The month was named for the Greek goddess Mayer, who was identified with the Roman era
goddess of fertility Bernadia, whose festival was held in May. But I guess more importantly for many of our listeners, May typically marks the start of summer vacation season in the United States and Canada. Let's start out tour of the night skies by looking east, where you'll see the constellations Scorpius, the scorpion in Greek mythology, the constellation was named the Scorpius, who was sent to Earth by the goddess Skaia in order to slay Arian the Hunter after he bursted
that he could kill all the animals on Earth. Scorpius stung Orion in the shoulder, but Orion's life was spared by Ophiucius the Healer, and it was placed in the heavens along with Scorpius, who continues to pursue him for eternity. I Ran the Hunter has become the hunted forever, with Scorpius rising in the east this time of year to triumphantly chase and defeat a Ryan who sits
in the west. Meanwhile, oh Fucius the Healer rises in the east, following behind Scorpius to chase and crush him into the earth as the Scorpion sets in the west. And so this ancient story continues to play out in the heavens year after year. Interestingly, parts of the story predate the Greeks, with Orion known in ancient Egypt as a Cyrus, the god of the underworld
and of regeneration. The brightest starr in Scorpius is Alpha Scorpie or Antarius, a scorpion's heart in ancient Greece, and Tari's name means the equal of Mars, the god of war. That's because it scored in orange, appearance is very similar to that of the red planet, and also because it passes very close to Mars every seven hundred and eighty earth days, easily seen with the
unaided eye. And Tarres is some five hundred and fifty light years away, but it looks so bright because it's around fifty seven thousand, five hundred times as luminous as the Sun and is one of the largest known stars in the
universe. And Tarres is a red supergiant about eighteen times the mass and eight hundred eighty three times the diameter of the Sun. Were it placed where the Sun is in our solar system, yielding golf, all the terrestrial planets Mercury, Venus, Earth, and Mars, and its visible surface would extend almost
as far at as Jupiter. A light year is about ten trillion kilometers, the distance of photon can travel in a year at three hundred thousand kilometers per second, the speed of light in a vacuum, and the ultimate speed limit of the universe. Astronomers believe and Harris began life around twelve million years ago as a spectrotype ORB blue star. Astronomers describe stars in terms of spectral types, a classification system based on temperature and characteristics. The hottest, most massive,
and most luminous stars are known as spectrotype blue stars. They're followed by spectrotype B blue white stars, then spectralotype A white stars, spectrotype F whitish yellow stars, spectral type G yellow stars. That's where our Sun fits in. Then there's spectrotype K iron stars, and the coolest and least massive stars
and learn as spectrotype M red stars. Each spectral classification system can also be subdivided using a numeric digit to represent temperature, with zero being the hottest and nine the coolest, and then you add a Roman numeral to represent luminosity. So put it all together and you can describe our Sun as being a G two V or G two five yellow dwarf star, one of millions spread across
our galaxy. Also included in the stellar classification system a special types LT and Y, which are assigned to fauled stars known as brown dwarves, some of which were actually born at spectral type M red stars but became brown dwarves after
losing some of their mass. Brown dwarves fit into a unique category between the largest planets, which are about thirteen times the massive Jupiter, and the smallest spectral type M red dwarf stars, which are about seventy five to eighty times the massive Jupiter or zero point zero eight solar masses like the similar sized red giant battle Girls in the constellation of Ryan and Tari's Laumost certainly end its life
as a spectacular type two or cork collapse supernerva, probably sometime within the next hundred thousand years or so. When it does explode at Lapierre as bright as the full moon for several months on end, and will be clearly visible during daylight hours here on Earth. And Taris has a companion star, Antari's B, located between two hundred and twenty four and five hundred and twenty nine astronomical
units away from the primary. An astronomical unit is the average distance between the Earth and the Sun, which is about one hundred and fifty million kilometers or eight point three line minutes. Special analysis of Antarrees B indicates it's pulling a lot of material off its bloated red super giant companion. Located near Antaries is
the M four globular cluster. Globular clusters are tight balls densely packed with thousands to millions of stars which were either all originally formed at the same time from the collapse of the same molecular gas and dust cloud, or alternatively, their galactic centers the remains of ancient galaxies that have been merged into the Milky Way Galaxy over billions of years. M four is composed of a million or so
stars originally born some twelve billion years ago. The M four globular cluster is located some seven thousand, two hundred lie years away, making it one of the nearest globular clusters to Earth. Easily seen through a pair of small binoculars, it covers an area of the sky is seen from Earth as big as the full moon. Astronomers estimate there are some one hundred and fifty or so
globular clusters orbiting in the halo of the Milky Way. Located near the tail of the scorpion are two open star clusters, known as M six and M seven. Open star clusters are loosely bound groups of a few thousand stars which are all originally formed from the same molecular gas and dust cloud at the same time, but are not as densely bound as globular clusters. Open clusters generally survive for a few hundred million years, with the most massive one surviving for
maybe a few billion years now. In contrast, the far more massive globular clusters exert fast, stronger gravitational attraction on their members, which is why they can survive so much longer. M six, which is also known as the butterfly cluster, is some twelve light years across and located about sixteen hundred light years away. It contains around eighty stars, which were all less than a
hundred million years old, which is quite young in cosmic terms. The M seven or Ptolemy cluster is named after the famous Greek astronomer a mathematician, Claudius Ptolemy. It's about nine hundred eighty light years away, and he's far more dispersed than him. Six, covering an area around twenty five light years across and at around two hundred million years, it's about twice as old. Born in the year one hundred, Ptolemay lived in Egypt while I was under Roman
rule. He wrote over a dozen scientific treaties, the first of which was an astronomical work now known as the Almagest. While some of his works were very insightful, much of it was error prone, and measurements were simply modified and changed to fit his theories. He's best known for refining a geometric theory for the universe, one which uses cycles and epicycles to place the Earth at the center of the cosmos, with all the other bodies orbiting around it.
Unlike most ancient Greek mathematicians, Ptolema's writings never ceased to be copied and commented upon, both in late Antiquity and in the Middle Ages. However, it's likely that only a few truly mastered the mathematics necessary to understand his works. That's evidenced by the many abridged and watered down introductions Totolem's astronomy that were popular amongst the Arabs and Byzantines alike. Galileo Galilee and Isaac Newton eventually overthrew his
geocentric theory more than a thousand years later. By the way, the m in terms like M four, M six, and M seven are abbreviations for Messier in honor of the eighteenth century French astronomer Charles Messier, who developed an astronomical catalog of fuzzy nebulous objects in the skies. See. Messier was a comet hunter, and he compiled the list of one hundred and three fuzzy objects
which one commets and served from his perspective, could be ignored. Later, other astronomers added additional celestial objects to the list, bringing the present catalog up
to one hundred and ten. Our solar system. In fact, most of the stars we see when we look up in the night sky are located in the Milky Way galaxies Orion Arm. The Orion Arm, also known as the Orion Spur or the Orion Signus Arm, depending on which name you prefer, is some three thousand, five hundred light years wide and around ten thousand light
years long. The Irian Arm is named after the Orion constellation, which is one of the most prominent constellations in the Southern Hemisphere summer and Northern Hemisphere winter.
Some of the brightest and most famous celestial objects in the constellation include battel Gers, Rigel, the stars of the Orion Belt, and the Orion Nebula, all located within the Orion Arm. The Orion Arm is located between the queen As Sagittarius Arm, which is more towards the galactic center from our position, and the Percy's Arm, which is more towards the outer edge of the
galaxy from our point of view. The Perseus Arm is one of the two major arms of the Milky Way, yeah, there being the Scutum Centaurus Arm long thought of as a minus structure spur if you will, between the two longer adjacent arms Perseus and Karna Sagittarius. Evidence was presented in mid twenty thirteen that the Orion Arm might actually be a branch of the Perseus Arm, or
possibly a completely independent arms segment itself within the Orion arm our. Solar System, Sun, the Earth, and all the other planets we know are located close to the Inner Rim in what's known as the Local Bubble, about halfway along the Orion Arms length, approximately twenty six thousand light years from the galactic center. The Local Bubble is a cavity in the interstellar medium in the Irione Arm, containing, among other things, the local interstellar cloud, which contains
our Solar System and the g Cloud. It's at least three hundred lights across, and it has a neutral hydrogen density of just zero point zero five atoms per cubic centimeter. There's just one tenth of the average for the interstellar medium across the Milky Way, at about a six that of the local interstellar cloud. The hot diffuse gas in the local bubble amidst X rays and is the result of a supernova that exploded sometime during the past ten to twenty million years.
It was once thought that the most likely candidate for the remains of the supernova was Jiminga, a pulsar and the constellation Gemini. However, later it was suggested that multible supernova in a subgroup be one of the plats moving group was more likely responsible becoming a rimnant supershell. Our solar system has been traveling through this region of space occupied by the local bubble for the last five to ten million years. Its current location is in what's known as the local interstellar
cloud, a minor region of slightly denser material within the bubble. The cloud formed when the local bubble and another bubble called the Loop one bubble met gas within the local interstellar cloud. As a density of about zero point three Adams per cubic centimeter. From what we can tell, the local bubble isn't spherical. It seems to be narrower, and the galactic plane becoming somewhat egg shaped or elliptical, and may even become wider above and below the galactic plane becoming
shaped more like an hour glass. And it's not alone. It's abutting other bubbles of lesser dense interstellar medium, including the Loop one Bubble. The Loop one bubble was created by super nervy instellar winds in the Scorpius Centauris association, some five hundred layers from the Sun. The Loop one bubble also contains the star and taris that we spoke about earlier. Astronomers have identified several well, I guess you'd call them tunnels, which connect the cavities of the local bubble
with that of the Loop one bubble. Collectively, they've been referred towards the Loopers tunnel, other bubbles which are adjacent to our local bubble, and then as the Loop two bubble and the Loop three bubble. Looks like astronomers still have a problem when it comes to thicking up cool names. Also visible this month is the Edder Akwards meteor shower, which is generated as the Earth passes
through the dust and debris trail left behind by Halley's comet. Comet P one Halley's a well known short period comet which visits the Inner Solar System every seventy five to seventy six years. The fifteen kilometer wide mountain of rock and ice
will make its next close up appearance in twenty sixty one. It's named in honor of the British astronomer Edmund Halley, who in seventeen oh five, after examining ancient Chinese, Babylonian and medieval European records, successfully predicted its return in seventeen fifty eight. However, he died in seventeen forty two before his prediction
could be confirmed. The comet's highly elliptical and elongated orbit takes it from between the orbits of Mercury and Venus out almost as far as the orbit of Pluto. Howe's orbit is in retrograde, meaning it orbits the Sun in the opposite direction to the planets, that is, clockwise, from above the Sun's northern
pole. This retrograde orbit results in at having one of the highest velossities relative to the Earth of any object in the Solar System traveling at some seventy point five six kilometus per second, or if you prefer, two hundred and fifty four thousand and sixteen kilometers per hour. As well as the eto Achard's meteor shower every May, Halley's comet also produces the Orionids meteor shower in Lead October.
Astronomers think Commet Halley was originally a long period comet which took thousands of years to travel to the Inner Solar System from the Aorc Cloud, but was gravitationally perturbed into its current orbit by close encounters with the giant outer planets. The Orc Cloud is a hypothetical sphere of comets and asteroids beyond the heliosphere, a mixture of vagabonds from the Solar System and objects from deep space which have
been collected by the Sun's gravitational pool. Occasionally, as the Sun passes by another star, an Orc Cloud object will get perturbed and be flunked towards the Inner Solar System. The Outer Akwards meteor shower runs from the nineteenth of April through to the twenty eighth of May, peaking around me The fifth, with around fifty five meteors an hour, making it one of the Southern Hemisphere's best
celestial showers. However, back in nineteen seventy five they were running ninety five meteors an hour, and in nineteen eighty it was up to one hundred and ten. Even better, the bright yellow meteors often appear as streaks known as trains. As their name suggests, they radiate out from the direction of the constellation Aquarius and the start at Aquary. Just look towards the east after midnight and before dawn for the best view. Jonathan Nelly's the editor of Australian Sky
and Telescope magazine. He joins us now for the rest of our tour of the May night skies on SkyWatch Stewart. Yeah, well, it's main hour. So if you're lucky enough to have some nice dark skies where you live, if you go out in the early evening, you'll see the Mookie Way stretching all the way across the sky from the southeast to the northwest. It's really quite a specky side if you can see it under dark skies with dark adapted eyes. That's our galaxy, seem from the inside. It's just absolutely
glorious. The brightest star in the night sky, Serious can be seen during May about halfway up from the western horizon. If you look out to the western you go halfway up the sky from the horizon to overhead because it is big bright star, and that's sirious, the brightest star in the night sky. A little bit further, sort of down to the south, there's another bright star. It's the second brightest star in the night sky. That's called
Canopus. And low down on the western horizon you can still make out the shape of the constellation a Ryan above the trees or houses, whatever, or on the horizon where you live. It's still there for only a few more weeks. Really, it's getting very very low now. It's making its last
appearance before disappearing from view for the next six months or so. Way down in the deep south of the sky, we've got the famous Southern Cross, of course, which at this time of the year is nice and high, and it's standing upright, so it looks like a sort of a kite shape, very small kite shape. To its left, you see two bright stars in the constellation Centaurus. Astronomers call them the two Pointers because if you draw
a line through them, it sort of points towards the Southern Cross. The two pointers are known as Alpha and Betasentauri, and if you look at Alpha a telescope, you'll actually see that it's two stars, and there's a third star as well. It's some distance away and too faint to be seen through sort of normal backyard telescopes. It's called Proximus Centauri, and Proximus Centauri is
actually the closest start of our solar system. It's a small star. It's very dim, so you really need to know where to look for it, and you need to have a big enough telescope. But if you just look towards Alpha Centauri, it's roughly there. So you're looking towards the postest star system to our star system. To the right of the Southern Cross, we've got the constellations Karna, Vela and Puppas, which is some of my favorite
area of the sky. It's just it's just wonderful. You look. You just get a pair of anoculars on the this and just sweep through this area. There are star clusters and niggling things. It's just glorious because it's in the milky way, and so there's lots of stuff to see. And yeah, yeah, it was a big constellation called Argo Navas the ship of the Argonauts, and got split up, and the three main constellations you've got split into Karna, Vela and Puppas. Pappas is the poop deck, Carina is
the keel, and Vila is the sales. And there was a fourth constellation as well. It's just nearby called Pixus, that's the compass. Would have been a big constellation. I mean, these things look nothing like, nothing like a ship, nothing like a sail or a poop deck or or whatever. It's just that people decided to put their favorite ideas or mythologies or garators that they're into the sky. So they made up their own join the dots fares. You would not to go out and look in the sky and think,
oh, look there's a big ship. You know, the sales and everything. So don't don't don't get full. Don't go out thinking you're going to see something like that. Now, down in this area of the sky, if you have dark enough skies and you've got to your eyes dark adapted, you should be able to spot something called the Omega Centauri star cluster which has about ten million stars in it, and it's about seventeen thousand light years
away. And there's also a galaxy down this part of the world too, that part of the sky I should say called NGC five one two eight. You often hear it called Centaurus A. It's about ten to fifteen million light years away, and there's a huge galaxy. But both of these things don't look like that to the naked eye, but you can just make them out as a little fuzzy dots. It looks like a star that's a bit fuzzy, and if you get some binoculars onto them that it really looks like a
fuzzy staff each of these things. And if you get telescope onto Raga Centauri or Centaursa, they really look quite tremendous. They're really really impressive things. So you can actually see these things with the naked eye just there's little, tiny fuzzy blobs. They may not look impressive, but when you look at a picture of what they really are and think, wow, my eyes are
actually seeing these things from ten million light years away. That's a huge black hole in Centaura, say too, because it's one of the biggest radio sources in the sky. Yeah. Look, that's why I called it NNGC five one two eighth when I interially spoke about it, because that's its catalog name. Pretty much everyone calls it Centaurus A these days, that Centaurus they really refers to the radio source that is inside and just say the black hole.
Because in the very early days of radio astronomy, when astronomers are pointing these radio tooles goes around the sky, they would find these big sources of radio ways and they didn't really know what they were. They could pinpoint them. It was pretty obvious that it was coming from this galaxy in this instance,
but they didn't really know what was producing these radio waves. There's Sagittarius AY, and there's there's Cassier PA, and there's centauraus A. There's quite a few of them like that, and as they found other ones in those constellations
called them BC whatever. So, yeah, it's an impressive galaxy. Add and when you look at a picture taken with a big telescope or even vamited telescopes these days, it's it's a weird looking galaxy, strange looking thing that it's big dust laying going through the middle of it, or rather around the outskirts of it. So this is why I say, when you go outside and if you can spot, if you can spot, if you get a star map and you can actually spot this thing with the naked eye. It's
just a little fuzzy blob, no brighter than a star. It doesn't look impressive that way, but when you think that you are actually seeing this galaxy from ten or more million light years away with your eyes, and that the light that is coming into your eyes right now left there ten million years ago, it's really quite incredible to its put space into perspective in it. We've talked about Proximus Centaura, that the closest start to Earth a few moments ago,
that's only just over four light years away. Centaurus A is over ten million light years away, So that's the sort of difference you can see just with the naked eye. It's incredible. Anyhow, moving on, we've got the northern half of the sky moving up to the north. Now, the northern half of the sky from our part of the world doesn't really seem to have many bright star fields at this time of year, at least during the evening. There are some famous constellations there that you can see, such as
Leo, Cancer and Virgo. Leo looks quite good. Virgos just this big, sort of seemingly empty space. But astronomers, amateur astronomers love Virgo because when you get a telescope out and have a look into that part of space, there are actually lots and lots of galaxies. They're too faint to be seen with the naked eye, but a telescope can pick them up, and they're just you're a huge galaxy cluster in the constellation Virgo. But you do
need a telescope to see them. But if you wait till after midnight, you're going to get some spectacular constellations coming up at this time of the year, rising over the eastern horizon. And I'm talking Sagittarius. I'm talking Scorpius, which most people know of Scorpio and most people have heard of those two constellations. And there's another couple called Scutum and Opayucas, which most people haven't heard of. But that part of the Milky Way region that these constellations are
in is amazing. It's a bit like I was talking earlier about Pappas and Villa and Karina, lots of things to see well, Sagittarius and Scorpius, so many things to see, our star clusters of various kinds, and Nebulian dark Nebulian star fields and things. It's just really tremendous. Even just binoculars are good enough if you've got dark skies to have to spend hours just looking
around that part of the sky really is incredible. And you know, that's one of the reasons why astronomy is so big in the Southern hemisphere, and why radio astronomy in particular has been big here is because we get a good view down here of the Sagittarius region, which is towards the center of our galaxy. When you look towards Sagittarius, you're looking towards the center of our galaxy. So you're looking right right into the middle of the city of stars
that we live in our galaxy. Right, So there's lots of things happening there and lots of things for astronomous and study. Now, let's see what's happening with the planets at the moment for this month. Venus is the main attraction at the moment. It's nice and bright in the northwestern sky after sunset, you really can't miss. It's because it's just big and bright. Mars is a little bit higher than Venus and a little bit further around to the
north. It's not as bright as Venus. It's just a sort of a medium brightness orange red sort of star. But if you take a look each night after sunset during this month, you'll see that those two planets are seeming to move towards each other, that the gap between them is narrowing down. They're not actually doing that in space, of course, it's just the line
of sight effect from our vantage point here on Earth. But by the end of June they're going to be right up closer to each other they are, so as the next four or five, six, seven weeks go, they're going to sort of slowly come to together in the western sky, and at the end of June they'll be right close to each other, which max mcare
a really really good view in this month. If you go out on the twenty fifth twenty fifth of May, you'll see that Venus and the Moon and Mars will all be roughly roughly in a straight line at the moon in between.
So they've got Venus, the Moon, and Mars. That'll be an easy way to identify those two planets if you're having any trouble, because you go out and see the Moon and you think and you say, right, oh, well, that bright star just below it, or that star and inverted commas, the bright star below it is the planet Venus, and that orangey red star just above them to the right, that's actually the planet Mars. So go out on the twenty fifty fign if you've got good weather and
have a look, and you'll be able to stop them quite easily. The other two main planets that are easy to see, Jupiter and Saturn, well they can be found in the early morning sky, so you're gonna have to get up early. At the start of May, Saturn is rising over the eastern horizon just after midnight and then it's visible for the rest of the night throught sunrise. Jupiter is coming up at about four am at the moment, so you've got to be really a night owl or an early birds at least
to see it coming up over the horizon. If you're getting up at six o'clock in the morning, is something that Jupiter will be some distance above the horizon and you can't miss Jupid or either because it's it's nice and big and bright. And if you're awake in the early hours of the morning on the fourteenth of May, take a look outside and you'll see the Moon and Saturn
very close to each other. So if you're having trouble figuring out which one of those things is Saturn, get outside early hours of May fourteenth and you'll see that bright looking thing just next to the moon is Saturn. And similarly, on the eighteenth, the Moon will have moved a little bit further along
in its orbit and then you'll have the Moon next to Jubiter. So if you don't know which one Jupiter is, have we looked in the early morning hours of the eighteenth and look for the moon and the bright thing right next to it will be Jupiter. And that stupart is the sky for this month. That's Jonathan Ally, the editor of Astray in Sky and Telescope Magazine,
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