moon news 1999

22 december 1999: brightest moon for decades

At 2100 GMT, the full moon occurred within hours of perigee (the Moon's nearest point to us in its orbit around Earth). It was also within days of perihelion (when the Earth is at its closest to the Sun), so that the sunlight reflected by the Moon was stronger than in the summer. All this coinciding with the day of the winter solstice, the longest night of the year in the Northern Hemisphere, when the Moon is at its highest point in the sky. The combined effect meant that the Earth's satellite appeared about 14% bigger and about 20% brighter than normal. But full moons in 1893, 1912, and 1930 were more brilliant, as will be one in 2052.

Full story from BBC News plus pictorial feature and Sky & Telescope

22 december 1999: lunar surface change: a false alarm

Two months ago it appeared that the Clementine spacecraft had obtained convincing confirmation of a spontaneous brightening on the Moon, called a transient lunar phenomenon (TLP), originally reported by telescopic observers on April 23, 1994. However, what at first appeared to be vindication for TLP observers has proved to be a false alarm. Once the images were carefully corrected for lighting geometry and other effects, the colour difference went away.

Full story from Sky & Telescope

26 november 1999: lunar link to volcanic past

French scientists have put forward an intriguing new theory for what caused catastrophic volcanic activity on our planet hundreds of millions of years ago, which led to the rise of the dinosaurs. Researchers from Paris and Strasbourg say the moon, already known to generate tides in the ocean, could have had a much greater impact on the Earth's early history than was previously thought. They suggest that three times in the history of life on Earth, the Moon, together with the Sun, caused oscillations in inside of the Earth which could account for some of Earth's more dramatic geological events, such as the splitting of continents and oceans.

Full story from BBC News

23 november 1999: leonid strikes the moon

Astronomers think they have witnessed a meteor striking the Moon, which may be the first such confirmed observation. Brian Cudnik from Houston, Texas, captured the event during last week's Leonid meteor storm. He saw a brief flash near the centre of the Moon's dark side at about 0446 GMT, which he estimated was at least as bright as some nearby stars. Astronomer David Dunham, observing near Washington DC, made a video recording of the event. Astronomers are now appealing for anyone else who may have seen the event to come forward.

Full story from BBC News

15 october 1999: evidence of transient lunar phenomena

The first unambiguous confirmation of a spontaneous change in a feature on the Moon has been reported. Amateur observers have claimed to witness dozens of transient lunar phenomena (TLPs) for decades, but most professionals found the reports unconvincing because the events were almost always seen only visually. Now, however, a group has found "before" and "after" images from the Clementine spacecraft for an TLP reported last April 23rd. The area in question, the "cobra head" at the beginning of Schröter's Valley near the crater Aristarchus, has often been the location of TLP sightings.

Full story from Sky and Telescope and BBC News

13 october 1999: no ice detected after lunar smash

The controlled crash of NASA's Lunar Prospector spacecraft on the Moon did not throw up any signs of water. Scientists reached this conclusion after digging through extensive data from Earth- and space-based observatories. The daring experiment, which destroyed the spacecraft, took place when the probe had reached the end of its useful life.

Full story from BBC News

24 august 1999: eclipse shadow unveils scientific mysteries

The drama is over and the Moon has passed over the Sun, but for scientists the work is just beginning. From the UK to India, they harnessed the darkness of the August 99 total solar eclipse to try to solve mysteries about the Sun and its effect on the Earth, generating masses of data which must now be interpreted. How solar storms strike the Earth and knock out satellites, why the Sun's atmosphere is much hotter than its surface and how the Sun's heat drives the Earth's climate are just some of the questions the researchers are asking.

Full story from BBC News

11 august 1999: millions watch last solar eclipse of the millennium

Despite disappointing weather conditions on many parts of its track across Europe and Asia, the great eclipse of 1999 has filled many millions with a sense of wonder.

Full story from BBC News plus special feature

28 july 1999: uranus takes the lead for moons

The discovery of two more moons orbiting Uranus means that the ice giant now has the largest family of satellites in the solar system, a total of 20. The two tiny moons, discovered by the team led by Dr J.J. Kavelaars of McMaster University in Canada, are less than 20 km in diameter, and travel in highly irregular orbits.

Full story from BBC News

20 july 1999: frustration on moonwalk anniversary

The 30th anniversary of the first landing on the Moon has been marked by the launch of an X-ray telescope on the space shuttle Columbia, and new revelations about the Apollo 11 mission. But it has also prompted many expressions of regret that the Apollo missions have not been followed by others.

Full story from BBC News

20 july 1999: apollo moon experiment still working

An experiment left on the lunar surface 30 years ago by the Apollo 11 astronauts still continues to return valuable data about the Moon. The lunar laser ranging reflector is used to determine the round-trip travel time of a laser pulse from the Earth to the Moon and back again, thereby calculating the distance between the two with incredible accuracy. The data gathered has shown us that the Moon is receding from the Earth at about 3.8 centimetres (1.5 inches) every year. It has also measured minute changes in the shape of the Earth as landmasses gradually change after being compressed by the great weight of the glaciers in the last Ice Age.

Full story from BBC News

9 june 1999: moon's tail spotted

A tail of sodium gas that streams out for distances of at least 800,000 kilometres (500,000 miles) behind the Moon has been observed better than ever before. The new observations were made on the nights following the Leonid meteor shower of November 1998. The sodium atoms were blasted into space as tiny meteorites struck the lunar soil, it is believed.

Full story from BBC News and Sky & Telescope

3 june 1999: prospector probe to be crashed

NASA has announced that its Lunar Prospector probe will end its mission in a blaze of glory by crashing into the lunar surface. It will impact with a force equivalent of a large car crashing at 1100 miles per hour. In the process, scientists hope to conclusively prove what the probe was sent to investigate: that large reserves of water ice exist on the Moon. NASA acknowledges that the chances of success are small, as the low orbit and shallow angle of descent will make it difficult to target a specific impact point.

Full story from BBC News

3 june 1999: radar finds moon's cold spots

The first three-dimensional images of the Moon's poles have taken using radar. The observations reveal deep craters in permanent shadow that could potentially contain water ice. The south pole appears particularly suitable. The new data will be vital in selecting and hitting a target for the crash landing of the orbiting Lunar Prospector spacecraft on 31 July. It is hoped to blast water vapour high enough out of a crater for observatories to confirm its presence.

Full story from BBC News

20 may 1999: new moon for uranus

A new satellite of Uranus has been found using photographs taken 13 years ago. Erich Karkoschka of the Lunar and Planetary Lab of the University of Arizona made the discovery by comparing photographs taken in 1986 by the Voyager 2 probe with more recent ones from the Hubble Space Telescope. Uranus' moon-count of 18 now equals that of Saturn.

Full story from BBC News

22 april 1999: prehistoric moon map discovered

A neolithic map of the Moon has been discovered which predates the oldest previously known lunar map by 4500 years. The map, which is carved into a rock in the prehistoric tombs at Knowth in County Meath, Ireland, was found by Dr Philip Stooke of the University of Western Ontario, Canada. He found it on a rock, originally named Orthostat 47, which had been excavated from the major neolithic burial site. The relationship between the shallow series of carved arcs and the Moon is not immediately apparent to the untrained eye as the circular limb is not shown, but this may have been drawn or painted on with materials which have subsequently worn away.

Full story from BBC News

24 march 1999: probe reveals lunar core

The "Grazing Impact" theory of lunar formation has been given a further boost by the latest data from NASA's Lunar Prospector probe. Scientists have reported that the Moon's iron core has a radius of between 140 and 280 miles (220 and 450 km), and contains around 4% of the satellite's total mass. This is a tiny figure when compared with the Earth's core, which represents some 30% of the planetary mass.

Full story from BBC News

7 january 1999: "moon illusion" explanation confirmed

A full Moon, seen close to the horizon, seems huge. However, once it climbs high in the sky it seems to "shrink" to normal size. Such perceptions - dubbed the "Moon illusion" - have been recognized since the Greek astronomer Ptolemy as early as the second century A.D. Eighteen centuries later, a father and son team of researchers put the illusion to the test and essentially confirmed what Ptolemy concluded: that the illusion arises because seeing an object across miles of "filled space" makes it look farther, bigger, and more impressive than when there are no visual cues to its great distance.

Full story from IBM research