August 16 – Asteroid 46 Hestia

Main belt asteroid 46 Hestia was discovered on August 16th 1857 from the Radcliffe Obsetvatory, Oxford, by N R Pogson. Hestia (Greek goddess of the hearth) is a “c type” body of about 124 km diameter. Pogson gave the honour of naming her to astronomer, coin collector, and veteran of the 1810-12 Siege of Cadiz, Admiral William Henry Smyth.


1873 – Discovery of asteroid 133 Cyrene.

1885 – Discovery of asteroid 249 Ilsa.

March 19 – 326 Tamara

1892   –   Asteroid 326 Tamara, discovered March 19 1892 by Johann Palisa.  It is a C-type asteroid of about 93 km wide in the main belt, named after Tamar the Great, Queen of Georgia.

Queen Tamar, and her father, George III of Georgia.

Queen Tamar, and her father, George III of Georgia.

1892  –  Asteroid 332 Siri was also discovered on March 19th 1892, but by Max Wolf at Heidelberg.  It’s a fairly small object, about 40km wide.  The origin of the name is not known, and I haven’t been able to find any likely candidates.  Part of the problem, of course, is that, as with the aforementioned Tamara, and the next on this page, Isara, the name could have been altered to fit some perceived idea of what an asteroid’s name should sound like.

1893  –  Asteroid 364 Isara was discovered by Auguste Charlois.  It is a member of the large Flora family of S-type asteroids, which may be parents of the L chondrite meteorites.  The Isère river, from which this asteroid derives its name, flows from the Alps and joins the Rhone near Valence in southern France.

1919  –  Karl Wilhelm Reinmuth discovers asteroid 911 Agamemnon, a “Greek camp” Jupiter Trojan of approximately 83 km radius (making it probably the second biggest).

Originally posted 2015. Updated 2017.


March 04 – Messier 85

1781  –  Messier 85, a lenticular (elliptical if you prefer) galaxy, was discovered on this day in 1781 by Pierre Méchain.  It can be found in the constellation Coma Berenices (named after the Egyptian queen Berenice II) and is about 60 million light years away, making it the northernmost galaxy in the Virgo Cluster, a collection of somewhere between 1,200 and 2,000 galaxies, on the periphery of which is our own local group.

M85 (image credit: NOAO / AURA / NSF)

M85 (image credit: NOAO / AURA / NSF)

There are hundreds of beautiful photographs of all manner of galaxies on the internet, but M85 is very under-represented by legal entities with relaxed media sharing policies, hence the above.

1861  –  Asteroid 64 Angelina discovered from Marseilles by Ernst Tempel.  Angelina is an E-type (containing enstatite) with a very high albedo (0.28) compared to many other asteroids.  It is named after an astronomical station operated by the Hungarian astronomer Franz Xaver von Zach.  For discovering Angelina (and 65 Cybele) Tempel received the ‘Lalande Prize’ from the French Académie des sciences.

1892  –  M-type (mainly metallic) main belt asteroid 325 Heidelberga was discovered today by Max Wolf.  If you’ve been following these pages closely the choice of name should come as no surprise, being the location of most, if not all, of Wolf’s discoveries. Heidelberga is reasonably large, at approximately 75 km in diameter.  Fuller details of Heidelberga’s physical and orbital characteristics can be found in the NASA JPL Small-Body Database browser.

1904  –  Birth of George Gamow, cosmologist, and early champion of the Big Bang theory.

1923  –  Birthday of Patrick Moore, amateur astronomer extraordinaire.

This post originally appeared in 2015, and was slightly updated in 2017.


December 22 – Asteroid 264 Libussa

Discovered on December 22nd 1886 by C H F Peters, asteroid 264 Libussa is an asymmetrical S-type main belt asteroid of somewhere between 50 and 60 km diameter.

It was named after Libussa (Lubossa or Libuše), a half-elf  daughter of the mythical Czech king Krok.  She eventually became the founder of the city of Prague, and ancestor of the whole Czech nation.

Libuse (photo credit: Palic Kap)

Libuse (photo credit: Palic Kap)

Today’s photo shows a detail from the Octárna Hotel, Kroměříž, Czech Republic.  This is alunette (a half moon shaped space) by local artist Max Švabinský. It shows Princess Libuse prophesying the glory of Prague.

There’s not a great deal more to say about Libussa, so it’s back to orbital characteristics.  To date we have come across aphelion (3.18 AU for this particular rock), perihelion (2.42 AU), semi-major axis (2.8 AU), longitude of ascending node (49.8°), and inclination (10.4°).  Today we add another important element of an asteroid’s orbit: the argument of perihelion.  For Libussa, this is 339.27°, and in orbital calculations it is depicted by the letter  ω.  It’s not a “w”, by the way, but a lower-case omega (the word means “great o”) the last letter of the Greek alphabet.  Remember that, because one of these days I’m going to work out how to put some of these calculations in this blog in the form of a table.

The argument of perihelion is the angle between the perihelion and the ascending node.  So if, for example, the value was 90°, that just means that the asteroid would be at perihelion when it reached the northerly point in its orbit.

1981  ⇒  Asteroid 323 Brucia becomes the first asteroid to be discovered by astrophotography, by Max Wolfe.


December 16 – Asteroid 351 Yrsa

Asteroid 351 Yrsa was discovered today in 1892 by Max Wolf.  There isn’t a great deal to say about it:  it’s in the main belt, and is about 40 km across.  It is thought to have been named after the wife of King Eadgils of Swedish legend.  her father, Helghe, who had only had a brief fling with her mother, visited the region where she lived years later and, not knowing she was his daughter, got her in the family way, as they say.   Unlike the average Greek god, who would have thought nothing of it, he did the decent thing and killed himself upon discovering the truth.

Lithograph depicting Yrsa

Lithograph depicting Yrsa

Max Wolf was a great friend of today’s birthday boy, Edward Emerson (E.E.Barnard, namesake of Barnard’s Star, one of the most closely observed objects in the Galaxy.  Barnard was mainly a prolific comet finder, discovering 17 in all (15 solo, and 2 co-discoveries), but he’s always going to be associated with the one star in my mind, because it was, and indeed may still be for all I know, the intended target of Project Daedelus, the mind-bogglingly ambitious unmanned interstellar mission proposed by the British Interplanetary Society.  When I was an impressionable teenager in the 1970’s, Daedelus seemed likely to happen “any year now”.  Unfortunately, 30 years later, they still haven’t quite got around to working out how to get the necessary helium-3 fuel back from Jupiter in order to get it to work, and I suspect that the cost in today’s money of a nuclear-powered spaceship bigger than a Saturn 5 and built in orbit would be rather more expensive than gold-plating the Isle of Wight or  buying Australia and Canada back.

E E Barnard

E E Barnard



December 15 – Janus

J R Hind discovered today’s main belt asteroid, 23 Thalia, from Hyde Park, London, on December 15th, 1852 (I’d like to see him try that nowadays). Thalia is an S-type asteroid of about 107 km diameter, located between the 3:1 and 5:2 Kirkwood gaps.

In Greek mythology, Thalia, daughter of Zeus and Mnemosyne, with a name derived from the verb “to flourish”, was the muse of comedy and pastoral poetry. She may or may not (depending on which source you believe) have been the mother of the Corybantes, attendants to the Great Mother of the Gods, and associated with particularly orgiastic rites.

We also have a moon today.  The discovery of Janus, one of the inner Saturnian satellites, is attributed to Audouin Dollfus, who first observed it on December 15th 1966. Three days later, Richard Walker also observed an object in the right place but at the wrong time, which caused confusion for a while, but was eventually found to be another moon, Epimetheus, which shares an orbit with Janus.

Janus, photographed by the Cassini probe (image credit: NASA / JPL / SSI)

Janus, photographed by the Cassini probe (image credit: NASA / JPL / SSI)

Janus is the two-faced Roman god of beginnings, entrances, gates, doors, etc. You should thank him the next time an automatic door opens for you. Janus is also one of the select group of deities after whom a month (January) is named, and strangely he has no Greek counterpart.

1965  –  launch of San Marco 1 by Italy. Being their first satellite, the Italians wisely did not fill it with lots of expensive equipment. It did, though, contain a couple of experiments to study the ionosphere, the layer of the atmosphere stretching from about 60 km to 1,000 km, a region you need to know about if you’re planning to become a space-faring nation, needing to send radio messages over great distances.

2000  –  Death of George Alcock, aged 88, hunter of novae and comets. I believe he found five of each (remarkable for south-eastern England), some of them from indoors using binoculars, and even occasionally through double glazing1!  His eyesight must have been unbelievable.

2014  –  Voyager 1 crossed the termination shock.


2015  –  Launch of Expedition 46 to the International Space Station.  This caused considerable press interest in my homeland (in fact I’m going to call it a frenzy) because in addition to Russian cosmonaut Yuri Malenchenko and American astronaut Tim Kopra, the three-man crew contained Tim Peake, the first Briton to float into the ISS (I was going to say “set foot aboard” the ISS, but I’ve seen the footage, and feet don’t feature much).  Because of the  numbering system they use at the ISS when crews overlap, these three also formed part of Expedition 47.

ISS Expedition 46 Patch

ISS Expedition 46 Patch

As a supporter of Port Vale FC, I was distraught to discover that one of Tim Peake’s tasks whilst on this mission was to unveil a flag featuring the name of our local rivals, Stoke City.  I’ve gone off him a little.


1   Journal of the British Astronomical Association, vol.111, no.2, p.64-66

December 10 – Asteroid 211 Isolda

Asteroid 211 Isolda, discovered on December 10th 1879 by Johann Palisa, is about as average as asteroids get.  It’s dark, in the main belt, C-type, 150-ish km across, and has an orbital period of 5.3 years.

So today, as well as mentioning those orbital characteristics of Isolda with which we all should now be familiar from previous posts (aphelion – 3.53 AU; perihelion – 2.54 AU; semi-major axis – 3.04 AU, and longitude of ascending node – 263.8°) I’m going to say that Isolda has an eccentricity of about 0.16.

Eccentricity is another fairly simple concept: it’s got very little to do with the behaviour of the English upper classes (you shouldn’t confuse eccentricity with lunacy) but a lot to do with the orbit of almost everything in the solar system being non-circular.  Eccentricity, if we’re talking about planets, moons, asteroids and most known comets, will be measured on a scale somewhere between zero (completely circular) and one (an “escape” orbit).  Planets have a fairly low eccentricities (Earth = about 0.017); asteroids are a bit more wayward (their average is ten times greater, at 0.17), and comets can be anything, with values near to, or even in excess of, 1.0 (eccentricities of more than 1 are reserved for comets that are being flung out of the solar system following their solar fly-by).  Neptune’s moon Triton has the lowest known eccentricity, at 0.000016.  This is about as circular as can be accurately measured.

Isolda, of course, is named after Isolde, (or Iseult of Ireland) the lover of Sir Tristan of Arthurian legend and Wagnerian opera.

Tristan and Isolde

Tristan and Isolde

Today’s photograph shows husband and wife team Ludwig and Malvina Schnorr von Carolsfeld, Wagner’s original 1865 Tristan and Isolde.  Ludwig was a heldentonor, the dramatic tenor typical of Wagnerian  protagonists. Soprano Malvina was the daughter of the Portuguese consul in Copenhagen, and was a great-grand-neice of David Garrick, giant of the English theatre.

1999  ⇒  Launch of ESA’s XMM-Newton (it stands for X-ray Multi Mirror Mission), the largest satellite to date to be launched by the European Space Agency (4 tonnes in weight and 10 meters long).

December 09 – Patrick Moore

There’s not a lot I can say that hasn’t already been said a hundred times or more about this chap, but it’s four years today since the passing, at the age of 89, of Sir Patrick Alfred Caldwell-Moore CBE, FRS, FRAS, singleton, leg spinner, xylophonist (if that’s the right word), RAF veteran, composer, cat lover, EEC hater, star of The GoodiesThe Morecambe and Wise Show and GamesMaster, general legend, and best all-round entertainer since Daffy Duck.  And it appears from the photograph that he also may have owned a telescope.

Patrick Moore (image credit: unknown).

Patrick Moore (image credit: unknown).

I’m not sure where I got that signed photograph from, but it lives inside my copy of Mrs Moore in Space, by Patrick’s mother, Gertrude.

I briefly met him a few times, donkey’s years ago: two of these were at speeches he was giving in the environs of North Staffordshire and South Cheshire, where I was restricted to standing in line waiting for an autograph, and twice were a little more informal at book signings I was involved with in my previous life as a bookseller.  I’d like to say how many books Patrick Moore wrote, but I’m not entirely sure they can be easily counted, as they stretch over such a long period, and had such wildly varied life spans.

To end on a sour note: it’s pantomime season, so boos and hisses to Macmillan publishers, who decided in 2016 to cease publication of “Patrick Moore’s Yearbook of Astronomy”.  Remind me to never buy any of their books again.

1892  ⇒  Discovery of the large main belt asteroid 349 Dembowska by French astronomer Auguste Charlois.  It was named in honour of the Italian astronomer Baron Ercole Dembowski, a specialist in double stars (and if the name sounds less than Italian, it’s because his father was a Polish general).  349 Dembowska is about 140 km wide, and is one of the brightest of the large asteroids.  It is classified as R-type, characterised by spectral lines showing the presence of olivine and pyroxene (the main constituents of the Earth’s mantle), and possibly plagioclase feldspars.


December 08 – Asteroid 5 Astraea

Asteroid 5 Astraea was discovered on this day in 1845 by Karl Ludwig Henke, and, as it was still relatively unusual to find asteroids at that time, it won him an annual pension of 1200 Marks from the king. Astraea is S-type, in the main belt, is quite big (roughly 167 km across at its widest point) and takes just over 4 years to orbit the Sun.

In Greek mythology, Astraea is the celestial virgin, and her name means just that (“star maiden”). She was a personification of justice, innocence and purity, and was the last of the immortals to live down here among us humans. Upon leaving Earth she became the constellation Virgo.


Yesterday we met the concept of the semi-major axis, and if you were paying attention you will know what I mean when I say that Astraea’s is 2.57 AU.  Today I’m attacking you with another position-related phrase, the longitude of the ascending node.  Like yesterday’s, it sounds more complicated than it is.  But unlike yesterday’s, it needs a really long rambling explanation, so here goes.

It’s an unwieldy phrase, isn’t it? So I’ll break it down into small parts. Firstly, if I tell you that for Astraea it is 141.7°, you’ll already know that it’s some sort of direction.  Longitude, as you know, is a coordinate showing the east-west position of something.  It tells you how many degrees you have to turn in an anti-clockwise direction from some point of reference in order to end up pointing at the place you want to be.  For example, your directions might tell you that if you’re standing in the car park looking at the church (point of reference) you need to turn 141.7° to see the pub (or just follow the smell of the beer).

Next, a node is the point at which an inclined (i.e. not horizontal) orbit crosses the horizontal plane on which your reference point lies.  For objects in the solar system we use the ecliptic(the plane marked out by the Sun’s apparent path across the sky) as the plane, and the First Point of Aries (ask me later – just accept it as a direction in the sky) as the point of reference.  There will be two occasions in each orbit when a body such as Astraea crosses this plane: one when it goes down below it, and another when it comes back above it. This second one is the ascending node.

So, the longitude of the ascending node is the direction you would need to be looking in order to see Astraea, if you knew precisely when it was about to start heading upwards above the ecliptic. Does that make sense?

A poem from Emerson to finish (“cap-a-pie” means from head to foot):


Each the herald is who wrote
His rank, and quartered his own coat.
There is no king nor sovereign state
That can fix a hero’s rate;
Each to all is vulnerable,
Cap-a-pie invulnerable,
Until he write, where all eyes rest,
Slave or master on his breast,

I saw men go up and down,
In the country and the town,
With this tablet on their neck,—
‘Judgement and a judge we seek.’
Not to monarchs they repair,
Nor to learned jurist’s chair;
But they hurry to their peers,
To their kinsfolk and their dears;
Louder than with speech they pray,—
‘What am I? companion, say.’
And the friend not hesitates
To assign just place and mates;
Answers not in word or letter,
Yet is understood the better;
Each to each a looking-glass,
Reflects his figure that doth pass.
Every wayfarer he meets
What himself declared repeats,
What himself confessed records,
Sentences him in his words;
The form is his own corporal form,
And his thought the penal worm.

Yet shine forever virgin minds,
Loved by stars and the purest winds,
Which, o’er passion throned sedate,
Have not hazarded their state;
Disconcert the searching spy,
Rendering to a curious eye
The durance of a granite ledge
To those who gaze from the sea’s edge.
It is there for benefit;
It is there for purging light;
There for purifying storms;
And its depths reflect all forms;
It cannot parley with the mean,—
Pure by impure is not seen.
For there’s no sequestered grot,
Lone mountain tarn, or isle forgot,
But Justice, journeying in the sphere,
Daily stoops to harbour there.

Ralph Waldo Emerson (1847)

1842    Birth of Alphonse Louis Nicolas Borrelly, the French astronomer who crops up in these pages every few weeks as a discoverer of asteroids.  He found 18 in all, and discovered or co-discovered six comets.


December 07 – Asteroid 423 Diotima

Asteroid 423 Diotima was discovered from Nice by Auguste Charlois on December 7th 1898. It’s in the main belt, is a C-type, is fairly large (approximately 170 by 140 km) and rotates about every 4.8 hours.

Diptima has a semi-major axis of a little over 3 AU.  Semi-major axis is a new phrase to these pages, but don’t panic: it’s just the longest radius of of an elliptical orbit.

Diotima of Mantinea

Diotima of Mantinea

Diotima was named, by the Astronomisches Rechen-Institut, after one of Socrates’ teachers, Diotima of Mantinea (if she ever existed – the jury is still out on whether or not she was simply a creation of Plato). It is from the teachings of Diotima that we get the concept of platonic love. I can’t help thinking there’s a clue to her existence (or lack of it) in that name. Surely it would have been diotimic love?