Apr 01

April 2009

What’s Up in the Sky April, 2009
By Peter Burkey

Sputnik, Voyager, Spirit and Opportunity are all probably names that are familiar to many with an interest in space science. These, along with the Hubble Space Telescope and the International Space Station have gained notoriety through media exposure and famous discoveries. But what about Stardust, J-MAPS, or Dawn? Although not as well known, these are spacecraft that are no less significant.

Orbiting the Sun since 1999, NASA’s Stardust spacecraft collected a tiny sample of dust as it flew by Comet Wild-2 in 2004. Two years later it sent its sample back to Earth in a capsule and receded into space. In 2005 the Deep Impact probe fired a projectile into Comet Tempel-1 but was unable to image the resulting crater due to obscuring dust and debris from the impact. Now NASA is sending Stardust back to Tempel-1 for a better look. It should arrive in February, 2011.

J-MAPS is a future mission that will map the distances, positions, and motions of millions of stars to extreme accuracy. While this does not have the glamour of Hubble photos, such a vast database is extremely important to astronomers’ understanding of our Milky Way galaxy.

The next Mars rover will dwarf Spirit and Opportunity – missions that were, incidentally, designed to last three months and are still going strong after more than five years! The Mars Science Laboratory, now scheduled for launch in the fall of 2011, will be the size of a small car, five times larger than the current rovers. Its main mission will be to assess the “habitability” of the planet to determine whether Mars’ environment is or ever was able to support life. It will be a mobile science lab with state-of-the-art instruments to evaluate the atmosphere, geology, and surface conditions of the planet.

The Dawn probe has been in space a little over a year. This spacecraft is unique in that it uses an ion propulsion system. This type of engine accelerates Xenon gas to a very high velocity for a very long time so it gets a small thrust for a long duration rather than a short, large push like that of a chemical rocket. Dawn will orbit and study the two largest protoplanets (asteroids), Ceres and Vesta beginning in 2011.

These spacecraft are just a few of the current and future missions that will further our understanding of what’s up in the sky.

This month in history:
April 1: Comet Hale-Bopp nearest Sun – 1997
April 8: Gemini 1 launched – 1964
April 12: Yuri Gagarin becomes first human in space – 1961
April 12: Columbia is first space shuttle to be launched – 1981
April 14: KSC and Vandenberg AFB chosen as shuttle launch sites – 1972
April 19: Surveyor 3 lands on Moon – 1967
April 21: First space funeral: cremated remains of 24 people launched into orbit aboard Pegasus rocket – 1997
Apr. 25: Deployment of Hubble Space Telescope – 1990

Here are this month’s viewing highlights:
Planets this month: After sunset Saturn is in SE below the constellation Leo. Mercury becomes visible near western horizon mid – month. Jupiter and Venus are easily visible in the predawn sky.
April 2: First quarter Moon.
April 9: Full Moon.
April 16-24: Look for Mercury above western horizon at dusk.
April 17: Last quarter Moon.
April 22: See crescent Moon near Venus before dawn near eastern horizon.
April 24: New Moon.