Royal Astronomical Society – January Astronomy/Space Digest

SPACE DIGEST: JANUARY 2005

This release contains a summary of some significant astronomical and space events that will be taking place during January. It has been written in order to assist the media in planning and researching future stories related to space science and astronomy, particularly those with UK involvement. It is not intended to be fully comprehensive. Dates and times may be subject to change.

EINSTEIN YEAR

2005 is Einstein Year, the UK’s contribution to the United Nations’ International Year of Physics, a celebration of the centenary of the publication of Einstein’s most famous work, including special relativity (and the famous equation e=mc2).

The Institute of Physics (IOP) in the UK and Ireland will be using this special year to highlight the contribution of contemporary physics to society through a programme of innovative activities. The IOP is encouraging individuals and organisations around the UK to run their own physics-based outreach activities in their communities during 2005.

A NAKED EYE COMET

Throughout January, astronomers in the northern hemisphere will be watching the recently discovered Comet Macholz as it tracks across the sky. It should be visible to the unaided eye until late January and well placed in the sky for UK observers.

During January, the comet will track northward, passing through the constellations of Taurus, Perseus and Cassiopeia as it heads toward the Pole Star, Polaris. In the first few days of the new year, it should be visible about 10 degrees to the west of the bright orange star Aldebaran (the “bull’s eye” in the V-shaped star pattern of Taurus).

On the night of January 7 – 8, it will sail about 2 degrees (4 Moon widths) to the west of the easily recognisable Pleiades star cluster, often known as the Seven Sisters.

The comet was discovered by Californian amateur astronomer Don Machholz on 27 August 2004. During early January it is about 52 million km from the Earth , though the distance increases after mid-month. It will be at its closest to the Sun (about 180 million km) on 24 January. However, rather unusually, the comet spends its entire life outside the orbit of the Earth.

To find Comet Machholz, it is best to select a dark observing site away from major cities and street lights. Anyone familiar with the winter sky should look to the right of the bright constellation of Orion and then search higher in the sky for Aldebaran and the Pleiades. In binoculars, look for an object that is fuzzy compared with the much more distant stars.

12 JANUARY: LAUNCH OF DEEP IMPACT COMET MISSION

NASA’s Deep Impact spacecraft is scheduled for lift-off from Cape Canaveral Air Force Station, Florida, no earlier than 12 January 2005. The spacecraft will then follow a six-month, 431 million km (268 million mile) trajectory to comet Tempel 1, where it will send a projectile crashing into the icy nucleus.

By crashing a spacecraft into a comet, scientists hope to get their first look at what kind of materials lie beneath the surface. When the Deep Impact spacecraft approaches Tempel 1 on July 4, 2005, it will release a small spacecraft that will crash into the nucleus at a speed of 36,800 km/h (23,000 mph). This impactor spacecraft is equipped with a camera that will take pictures as it approaches the comet’s surface.

The outcome is not certain, but scientists expect the spacecraft to blast a stadium-sized crater ranging somewhere between two to fourteen storeys deep on the surface of the 3.75 ml (6 km) wide comet, spraying dust, gas and ice into space for hours afterward. By looking at the spectra of the ejected impact material, scientists will be able to determine for the first time the chemical composition of that material.

13–14 JANUARY: RAS DISCUSSION MEETING – WIDE-FIELD SPECTROSCOPY: SCIENCE WITH, AND BEYOND, 2DF

A two-day discussion meeting will be held at the Geological Society Lecture Theatre, Burlington House, Piccadilly, London W1. The times are:
Jan 13, 10:30-17:30 Two-day Wide-Field Spectroscopy Meeting (Day 1);
Jan 14, 10:30-15:30 (Day 2)

Over the past decade the Anglo-Australian Observatory has pioneered the use of optical fibres in astronomy and currently leads the world in this work. The latest of these instruments, the Two-Degree Field facility (or 2dF) uses flexible optical fibres to simultaneously collect the light from up to 400 faint stars or galaxies over a two degree field of view. (Two degrees of sky is about four Moon diameters across.) This light is directed to a spectrograph, where the 400 individual spectra are detected by a CCD for analysis.

One of the main reasons behind the development of the instrument was The 2dF Galaxy Redshift Survey, a joint UK-Australian project whose goal was to carry out a redshift survey of 250,000 galaxies and make a 3-D map of the southern sky.

This two-day RAS meeting will review the major scientific results from the successful operation of the Anglo-Australian Telescope’s Two-Degree Field facility and look forward to future developments in wide-field spectroscopy.

The 2dF facility was originally proposed in 1988 and became operational in 1997. Within 2 years of operations, 2dF acquired more astronomical spectra than any previous instrument, and remains a workhorse facility for the Anglo-Australian Observatory. After seven years of hard service, 2dF is shortly to be revitalised by a major upgrade: the AAOmega facility.

14 JANUARY: RAS DISCUSSION MEETING – SEISMOLOGY OF THE SUN: FROM THE INNER CORE TO CORONA

English Heritage Lecture Theatre, (formerly the Scientific Societies’ Lecture Theatre), Savile Row, London W1S 2ET)

High-resolution spacecraft missions and well-established ground-based networks, such as BiSON and GONG, have opened up a new era in the investigation of solar structures by making direct or indirect observations of wave activity in the Sun. Recent observations by the TRACE spacecraft of waves in the Sun’s corona have led solar scientists to the determination of previously unknown physical parameters in the corona, and this has given birth to the field of Coronal Seismology. The accumulation of longer, better-quality, and higher-resolution data in helioseismology also continues to open up exciting new areas of investigation.

14 JANUARY: HUYGENS’ DESCENT TO TITAN’S SURFACE

The European Huygens probe, which separated from the Cassini spacecraft on 25 December 2004, is scheduled to enter the atmosphere of Saturn’s moon Titan, on 14 January. The descent begins around 09:07 GMT, and, if all goes well, the probe should reach the satellite’s surface after approximately two and a half hours. More than 1,000 images and other data will be obtained during the descent and transmitted to the Cassini orbiter, where they will be stored and later relayed to Earth.

The nature of Titan’s surface is still unknown, so it may make a hard landing on rock-hard ice, it may splash into a lake of liquid hydrocarbons, or it may squelch into a thick layer of organic sludge. There is a time delay on communications between Cassini and Earth of 66 minutes. Data sent via Cassini will reach the NASA ground station on Earth in mid-afternoon.

A UK press briefing to mark the historic event will be held at The Royal Society, Carlton House Terrace, London, 15.00 hrs – 18.30 hrs. (Registration from 14.30 hrs)

This will include live coverage from ESA Operations Control Centre in Darmstadt, Germany.

The event will provide direct comment and status updates from UK scientists (Prof. John Zarnecki and colleagues) and Prof. David Southwood (ESA Director of Science), including the ESA press briefing when the initial results from Huygens will be announced.

UK scientists are playing significant roles in the Cassini Huygens mission with involvement in 6 of the 12 instruments onboard the Cassini orbiter and 2 of the 6 instruments on the Huygens probe. The UK has the lead role in the magnetometer instrument on Cassini (Imperial College) and the Surface Science Package on Huygens (Open University).

UK industry had developed many of the key systems for the Huygens probe, including the flight software (LogicaCMG) and parachutes (Martin Baker).