Astrognome Scrapbook Themisto

Themisto

Themisto also known as Jupiter XVIII is a small irregular satellite of Jupiter was discovered on September 30^th 1975, the subsequently lost, and rediscovered in 2000.

Themisto seen moving against starry background

Themisto was first discovered by Charles T. Kowal and Elizabeth Roemer, however, not enough observations were made to establish an orbit and it was subsequently lost. Then, in 2000, a seemingly new satellite was discovered it was soon confirmed that this was the same as the one observed in 1975.

Themisto only has a radius of about 4 kilometres and takes around 129 days to orbit Jupiter.

Astrognome Scrapbook Ananke

Ananke

A small irregular shaped moon of Jupiter discovered on Wednesday 28^th 1951 by Seth Nicholson at Mount Wilson observatory in America. Ananke moves in a retrograde or in the wrong direction compared to most of the other moons that orbit Jupiter.

Although discovered in 1951 Ananke did not receive its present name until 1975, before then it was simply known as Jupiter XII. The radius of Ananke is about 14 kilometres and takes around 610 day to orbit Jupiter.

The Astronomy Show

The Astronomy Show

On Drystone Radio this Wednesday on The Astronomy Show there will be news of the dramactic results coming back from Europa of water geysers being seen by the Hubble Space Telescope.

The A-Z of constellations continues with Auriga the Charioteer one of the really great constellations.  After last week’s power cut we will try again to highlight M6 in Serpens with The Messier Marathon, and the list of bright stars continues this week with Procyon.

 This plus the astronomical scrapbook, the latest astronomy news, together with what can be seen in the night sky this week plus the astronomical society news.

The Astronomy Show, every Wednesday between 3 pm and 5 pm with Martin Lunn on Drystone Radio 103. 5 FM listen on line at www.drystoneradio.com  or hear me via podcast.  You can contact me at Drystone radio on martin.lunn@drystoneradio.com

If you missed the Astronomy show on Wednesday 28th September it is available on podcast for 30 days.

Go to www.drystoneradio.com and check the podcasts.  

Astrognome Scrapbook Daniel Kirkwood

Daniel Kirkwood 

Daniel Kirkwood was born in Harford County, on September 27^th 1814 Maryland, USA.  He graduated in mathematics from the York County Academy in York, Pennsylvania in 1838.

Kirkwood's most significant contribution to science and mathematics came from his study of asteroid orbits. When arranging the then-growing number of discovered asteroids by their distance from the Sun, he noted several gaps, now named Kirkwood gaps in his honour, and associated these gaps with how Jupiter affected the asteroids. Kirkwood also suggested a similar affect was responsible for Cassini Division in Saturn's rings, as the result of one of Saturn's moons.

He was the first to correctly suggest that the material in meteor showers is cometary debris.

Daniel Kirkwood died on June 11^th 1895

Astrognome Scrapbook A real Blue Moon

A real Blue Moon

On the 26^th September 1950 a blue moon was sighted over the Scotland and the north of England. It was the night of an eclipse of the Moon. A lunar eclipse occurs when the Moon passes into the shadow of the Earth and then usually appears to turn a coppery red colour. This is caused by the light passing through the Earth’s atmosphere before reaching the Moon. It is then bent or refracted and most of the light reaching the Moon is at the red end of the spectrum rather than all the normal white light made up of all the colours of the spectrum.

It was a very strange sight that was caused by an enormous and devastating wild fire in Canada. Smoke from the forest fires crossed the continent and across the Atlantic, it then reached Great Britain. The ash that was caused by the fires affected the light and caused it to be bent again towards the blue end of the spectrum causing the Moon to appear blue.

This was dramatically highlighted in 1991 when the volcano Mount Pinatubo in the Philippines erupted sending massive amounts of ash into the upper parts of the atmosphere. The Moon went a very dark inky blue colour.

A blue moon has become shorthand for an extremely rare event. The Moon turning blue that night caused a certain amount of panic and concern, there were rumours that this was some form of retribution descending over the universe for our atomic meddling’s, or worse, the first sign that the Earth was about to do something eccentric like freezing solid or blowing up.

Today the term blue moon is used to describe the second full moon in a calendar month. 

Astrognome Scrapbook R Scutum

R Scutum

R Scutum was discovered on September 25^th 1795 by Edward Pigott one of the fathers of variable star astronomy while he was living in the city of Bath in England. At the time of the discovery of R Scutum there were few variables stars known. Variable stars are that very in brightness over a period of time.

R Scutum is a giant star that varies between magnitude 4.2 and 8.6 over a period of around 140 days. Its spectral class changes from G to K. It is the brightest of the RV Tauri type stars (These variables are very luminous stars and are typically given a supergiant spectral luminosity class. However they are relatively low mass objects, not young massive stars. They are thought to be stars that started out similar to the sun but evolved differently).

When at its brightest it is visible to the naked eye, but at its dimmest you will need good binoculars or a small telescope to locate it. In the sky it is about 1 degree or 1 finger width northwest of the Wild Duck Cluster (Messier 11).

Astrognome Scrapbook Mars Climate Explorer

Mars Climate Explorer

On 23^rd September 1999 NASA lost the $125 million spacecraft Mars Climate Explorer, as it reached Mars.

Unfortunately one engineering team used metric units while another used English units for a key spacecraft operation, for that reason, information failed to transfer between the Mars Climate Orbiter spacecraft team at Lockheed Martin in Colorado and the mission navigation team in California.

"People sometimes make errors," said Edward Weiler, NASA's Associate Administrator for Space Science in a written statement. "The problem here was not the error, it was the failure of NASA's systems engineering, and the checks and balances in our processes to detect the error. That's why we lost the spacecraft."

The navigation mishap pushed the spacecraft dangerously close to the planet's atmosphere where it presumably burned and broke into pieces, killing the mission on a day when engineers had expected to celebrate the craft's entry into Mars' orbit.

The space craft had completed a nearly 10 month journey when it reached Mars, its mission was to relay data from an upcoming mission called Mars Polar Lander, and help understand the early climate on Mars.

Astrognome Scrapbook Gustav Holst

Gustav Holst

Gustav Holst was born on 21^st September 1874 in Cheltenham, England, although he composed many important musical works including the opera Sita, composed during 1899–1906; The Hymn of Jesus, for chorus and orchestra in 1917, he will always be best known for writing the Planets suite, the idea began in 1913,  Holst was interested in astrology.

They planets were composed as follows.

Mars, the Bringer of War (1914)

Venus, the Bringer of Peace (1914)

Mercury, the Winged Messenger (1916)

Jupiter, the Bringer of Jollity (1914)

Saturn, the Bringer of Old Age (1915)

Uranus, the Magician (1915)

Neptune, the Mystic (1915)

Gustav Holst died on the 25^th May 1934

The Astronomy Show on Drystone Radio

The Astronomy Show on Drystone Radio

On Drystone Radio this Wednesday on The Astronomy Show I will be celebrating the anniversary of the discovery of the planet Neptune on 23^rd September 1846. 

The A-Z of constellations continues with Aries the Ram, I will be looking at  M6 in Scorpius in The Messier Marathon and the list of bright stars continues this week with Rigel. 

This plus the astronomical scrapbook, the latest astronomy news, together with what can be seen in the night sky this week plus the astronomical society news.

The Astronomy Show, every Wednesday between 3 pm and 5 pm with Martin Lunn on Drystone Radio 103. 5 listen on line at www.drystoneradio.com  or hear me via podcast.  You can contact me at Drystone radio on martin.lunn@drystoneradio.com

If you missed the Astronomy show on Wednesday 21st September it is available on podcast for 30 days.

Go to www.drystoneradio.com and check the podcasts.  

Astrognome Scrapbook Lunar Eclipse 331 BC

Lunar Eclipse 331 BC

On the 20^th September 331 BC eleven days before the victory of Alexander the great over Darius of the Persian emperor at Arbela in Assyria, there was an eclipse of the Moon when it appeared the colour of blood as recorded by Plutarch and Pliny. 

Astrognome Scrapbook Ole Rømer

Ole Rømer

Ole Rømer died on the 19^th September 1710.

He was born on September 25, 1644, in Århus, Denmark, little is known of his early life, however he was invited to join the observatory at Uraniborg to  work on observations made by Tycho Brahe from 1664-1670.  

In 1671 over a period of several months, Jean Picard and Rømer observed about 140 eclipses of Jupiter's moon Io, while in Paris Giovanni Domenico Cassini observed the same eclipses. By comparing the times of the eclipses, the difference in the longitudes of Paris and Uraniborg was calculated.

Rømer noticed upon examination of the data that he collected along with the observations of Cassini that the times at which the satellite Io emerges from the shadow of Jupiter in each of its revolutions about the planet are continually lengthened as the earth recedes from Jupiter, while in a similar but reverse manner, the times between emergences are shortened as the earth approaches Jupiter.

Rømer did not actually calculate the speed of light from his observations. At the time, the distance between the sun and the earth was still only a roughly calculated quantity, while the earth's elliptical path around the sun meant that the distances between the earth and Jupiter did not accrue uniformly, but varied in a complex manner according to the time of year and the position of the earth in its orbit. It would be left to later investigators to pin down an actual speed of light based on these phenomena.

In his Mathematical Principles of Natural Philosophy (1713), Isaac Newton credits Rømer as the first to observe the velocity of light through observations of Jupiter's moons.

Astrognome Scrapbook Hyperion

Hyperion

Hyperion is one of the largest irregularly shaped objects in the solar system. In fact it was the first non-round moon to be discovered. Hyperion is a moon of the giant ringed planet Saturn. It was discovered on September 16^th 1848 by William Bond, George Bond and William Lassells.

Hyperion is 255 by 163 by 137 miles in size, the moon spins approximately once every 13 days on its 21-day trip around the planet. However, its odd shape keeps it from a predictable rotation.

Astrognome Scrapbook Planetary Conjunction 1186

Planetary Conjunction 15^th September 1186

On September 15^th 1186 there was a close conjunction of planets in the evening sky with Mercury, Venus, Mars, Jupiter and Saturn all being within 13 degrees of each other just as the sun set. The Moon in September 1186 was new on September 18^th so was not visible during this conjunction.

On May 17, 2000, five solar-system planets Mercury, Venus, Mars, Jupiter, Saturn plus the moon were within 19 degrees of each other. It was a notable heavenly conjunction. All manner of natural catastrophes were predicted but failed to materialize.

And just like the conjunction in 1186 of which I am sure there were many dire warnings of catastrophes humanity survived nicely!!

Astrognome Scrapbook Leda

Leda

On September 14^th 1974 the moon Leda was discovered by Charles Kowell at the Mount Palomar observatory. Leda is the 9^th and smallest moon of Jupiter. Leda is only about 10 miles in diameter. 

The moon takes 239 days to orbit Jupiter.

Astrognome Scrapbook Luna 2

Luna 2

On September 14^th Luna 2 became the spacecraft to reach the surface of the Moon and the first man made object to land on another celestial body. It was the second Russian space craft sent to the Moon.  An earlier probe Luna 1 had bypassed the Moon. Luna 2 was not designed to soft land on the Moon rather to impact it. The technology needed to perform this task had not yet been devised. The probe was designed to send information back to Earth right up until the moment of impact.  Luna 2 crashed into Mare Imbrium the Sea of Showers or Sea of Rains.

There were no cameras on the space craft but a number of experiments on board which sent back valuable information to scientists that would help in planning future missions to the Moon.

Although Luna 2 was a huge success for the Soviets it also helped the U.S. by starting a trend of crash landing. It would eventually lead to the U.S.-made Rangers which would go on to also crash land on the moon in exactly the same way and help pave the way for the manned Apollo missions.

Astrognome Astronomy Show

Astronomy Show 14.09.16

On Drystone Radio this Wednesday on The Astronomy Show I will be continuing the A-Z of constellations with Ara the Altar, looking at M5 in Serpens in The Messier Marathon and the list of bright stars continues this week with Capella. This plus the astronomical scrapbook, the latest astronomy news, together with what can be seen in the night sky this week plus the astronomical society news.

The Astronomy Show, every Wednesday between 3 pm and 5 pm with Martin Lunn on Drystone Radio 103. 5 listen on line at www.drystoneradio.com  or hear me via podcast.  You can contact me at Drystone radio on martin.lunn@drystoneradio.com

If you missed the Astronomy show on Wednesday 14th September it is available on podcast for 30 days.

Go to www.drystoneradio.com and check the podcasts.  

Astrognome Scrapbook Luna 16

Launch of Luna 16

Luna 16 which was launched on September 12^th 1970 was a Russian unmanned probe sent to the Moon and then return with a sample of moon rock.

It was Russia’s first successful lunar sample return mission; there had been 5 earlier failures.  Following Apollo 11 and 12 it was the third mission to return samples of the Moon to Earth.

Luna 16 landed in the Mare Fecunditatis (the "Sea of Fecundity" or "Sea of Fertility") on September 20^th. Three days later on September 24^th Luna 16 returned safely to Earth bringing with it 101 grams of lunar soil.

The soil samples were similar to those that were brought back by Apollo 12 which had landed in Oceanus Procellarum the Ocean of Storms.

This mission accomplished the first fully automatic recovery of soil samples from the surface of an extra-terrestrial body.

Astrognome Scrapbook Amalthea

Amalthea

Discovered on September 9^th 1892 Amalthea was the fifth of Jupiter’s satellite’s to be discovered. It is discovered by Edward Bernard.  It is the third moon in distance from Jupiter and was the last moon to be discovered visually. In future all would be discovered photographically. It was  the first new satellite of Jupiter since Galileo Galilei's discovery of the Galilean satellites in 1609/10.

It is a small moon with dimensions of 250 × 146 × 128 km. Amalthea orbits Jupiter at a distance of around 181,000 km. 

Astrognome Scrapbook James Van Allen

James Van Allen

An American space scientist James Van Allen was born on September 7^th 1914, he was instrumental in the study of radiation belts around the Earth. He supervised the testing and use of captured German V-2 rockets for upper atmosphere exploration.

He was one of the scientists who proposed a program of worldwide cooperation in research, the International Geophysical Year (IGY) of 1957–58. The instrumentation of the early Explorer satellites, part of the United States’ IGY program, was built by Van Allen and his associates.

Launched on Jan. 31, 1958, Explorer 1 was the first successful U.S. space satellite. The information on cosmic radiation gathered by the Explorer satellites led to the discovery of radiation belts that surround the Earth. Today they are called the Van Allen Belts

James Van Allen died on August 9^th 2006.

Astrognome Astronomy Show

The Astronomy Show 

On Drystone Radio this Wednesday on The Astronomy Show I will be continuing the A-Z of constellations with Aquila the Eagle, looking at M4 in Scorpius in The Messier Marathon and the list of bright stars continues this week with Vega. This plus the astronomical scrapbook, the latest astronomy news, together with what can be seen in the night sky this week plus the astronomical society news.

The Astronomy Show, every Wednesday between 3 pm and 5 pm with Martin Lunn on Drystone Radio 103. 5 listen on line at www.drystoneradio.com or hear me via podcast.  You can  contact me at Drystone radio on martin.lunn@drystoneradio.com

Astrognome Scrapbook comet Halley 684 AD

Halley’s Comet 684 AD

Halley’s Comet 684 AD comet Halley was sighted on September 6^th 684 Ad in the west, it had a tail 10 degree long.  The Chinese described it as a broom star. After 49 days it went out of sight. It was recorded by Chinese and also by Japanese astronomers.

The comet was also reported in the west it was reported in Italy and this recorded was found in the Nuremberg Chronicles which was an illustrated story of human history related to the bible.

Halley’s Comet returns to the Sun about every 76 years. It will return again in 2061.

Astrognome Scrapbook Voyager 1

Voyager 1

The Voyager 1 mission was part of the NASA grand tour of the solar system. It was launched on September 5^th 1977, 16 days after its twin Voyager 2. Their missions were to explore the distant parts of the solar system.

Voyager 1 flew past the gas giants Jupiter and Saturn and sent back incredible images and information that scientists are still studying today. Amongst the many discoveries made by Voyager 1 was that the moon Io had active volcanoes, it was the first object other than the Earth for this to be seen happening. Io was one of the moons that was discovered by Galileo in the winter of 1609/10.

When the probe flew past Saturn and sent back incredible images if the ring system it also examined Titan the largest moon of Saturn. Although it was not possible to see the surface of Titan due to the thick atmosphere there was an indication that there was liquid on the surface. The Cassini mission has indeed conformed that there is liquid on Titan, not water of course but methane.

Voyager 1 then continued on its mission flying to the edge of the solar system and in 2012 scientists confirmed that Voyager 1 was at the very edge of the solar system. It is expected that Voyager 1 will continue working until about 2025.

Astrognome Scrapbook Gregorian Calendar

Gregorian Calendar

In October 1582 the new Gregorian calendar was introduced by Pope Gregory XIII, it replaced the Julian calendar introduced by Julius Caesar to make the calendar more accurate. Most Catholic countries in Europe followed suit but protestant countries like England did not introduce it until 1752.

To align the calendar in use in England to that on the continent, the Gregorian calendar was adopted: and the calendar was advanced by 11 days: Wednesday 2 September 1752 was followed by Thursday 14 September 1752. The year 1752 was thus a short year 355 days.

Some reports say that there were riots in the country when people realised that they were going to lose 11 days!!