20 June 2010
Today is the Summer Solstice.
What does this mean for regular folks? Well not much… Mostly it means that today is the longest day and at midday the Sun is as high in the sky as it gets during the year. In many countries this day marks the start of summer. Happy days…
Astronomically it is the day when the Earth’s axis tilt is most inclined towards the Sun. In the northern hemisphere this happens around the 20th or 21st of June and in the southern hemisphere around the 21st or 22nd of December.
In the image above (taken from APOD) the Sun is photographed at the same time of day throughout the year. The path it traces is called an analemma. Summer Solstice occurs on the day the Sun is at its highest. The figure of eight is caused because the Earth’s orbit is slightly elliptical and the Earth moves faster in its orbit when closer to the Sun. This means that in some parts of the year the Sun is further along in its path over the sky and at others it is behind.
11 August 2009
Diamond ring at third contact. These images of the eclipse were taken from Tian Huang Ping, Anji, China.
This sequence took about 21 seconds in real time.
25 May 2009
On May 25, 1961, President John F. Kennedy announced before a special joint session of Congress the dramatic and ambitious goal of sending an American safely to the Moon before the end of the decade. A number of political factors affected Kennedy’s decision and the timing of it. In general, Kennedy felt great pressure to have the United States “catch up to and overtake” the Soviet Union in the “space race.” Four years after the Sputnik shock of 1957, the cosmonaut Yuri Gagarin had become the first human in space on April 12, 1961, greatly embarrassing the U.S. While Alan Shepard became the first American in space on May 5, he only flew on a short suborbital flight instead of orbiting the Earth, as Gagarin had done. In addition, the Bay of Pigs fiasco in mid-April put unquantifiable pressure on Kennedy. He wanted to announce a program that the U.S. had a strong chance at achieving before the Soviet Union. After consulting with Vice President Johnson, NASA Administrator James Webb, and other officials, he concluded that landing an American on the Moon would be a very challenging technological feat, but an area of space exploration in which the U.S. actually had a potential lead. Thus the cold war is the primary contextual lens through which many historians now view Kennedy’s speech.
The above clip is from NASA’s page on President Kennedy’s announcement of the decision to go to the Moon.
Here is an audio recording of the speach I found on YouTube.
Twelve people have walked on the surface of the Moon.
- Neil Armstrong – Commander
- Edwin E. Aldrin, Jr. – Lunar Module Pilot
- Charles Conrad, Jr – commander
- Alan L. Bean – lunar module pilot
- Alan B. Shepard, Jr – Commander
- Edgar D. Mitchell – Lunar Module Pilot
- David R. Scott – Commander
- James B. Irwin – Lunar Module Pilot
- John W. Young – Commander
- Charles M. Duke Jr. – Lunar Module Pilot
- Eugene A. Cernan – Commander
- Harrison H. Schmitt – Lunar Module Pilot
Apollo 17 left the surface of the Moon on 14th December 1972. We have not been back since then.
19 April 2009
The following is taken from this article in The Guardian.
JG Ballard, novelist and short-story writer, has died after a long battle will illness, his agent has said.
The 78-year-old author, who was best known for the award-winning Empire of the Sun, a semi-autobiographical novel written in 1984, and his controversial novel, Crash, later adapted into film by David Cronenberg.
His agent, Margaret Hanbury, said it was “with great sadness” that Ballard had passed away this morning after several years of ill health.
Member of the New Wave of science fiction authors, JG Ballard was one of the first science fiuction authors I read in the sixties. I remember reading The Drowned World, The Crystal World and The Terminal Beach (which I still have in my library). Not my favorite science fiction author – too “psychological” for my taste – I was in to hard science fiction.
20 March 2009
Today at 11:44 UTC (roughly the same as GMT).
The center of the Sun crosses the equatorial plane from south to north. On the equator the sun passes directly overhead. At the poles the Sun is on the horizon the whole day. On this day the Sun spends roughly the same length of time over and under the horizon so day and night are roughly equally long at all places on Earth.
Vernal equinox comes from the latin ver = spring, aequus = equal and nox = night (day and night of equal length).
15 March 2009
The Ides of March is the fifteenth day of March in the Roman calendar. Ides comes from latin and means half division.
A bad day for one: on the 15th March 44 BCE Julius Caeser was assainated by Marcus Junius Brutus, Gaius Cassius Longinus, Decimus Junius Brutus and several other Roman senators. He was stabbed to death. Beware the Ides of March.
A triumphant day for another: on 15th March 1493 Christopher Columbus returns to Spain after his first journey to the Americas.
An innovative day for technology: on 15th March 1985 the first internet domain name (symbolics.com) is registered.
14 March 2009
Giovanni Schiaparelli was born on this day in 1835. He is perhaps best known because, as noted in Wikipedia:
he observed a dense network of linear structures on the surface of Mars which he called “canali” in Italian, meaning “channels” but mistranslated as “canals”.
Interestingly (or not) Google celebrates his birthday with this logo: