Cap'n Bob & the Damsel

Astronomy

The Sky is NOT Falling – Yet

NASA – NASA Satellites Observe Comet’s Trail

There will be no tsunamis, firestorms or mass extinctions to spoil your Memorial Day weekend.

Image right:This infrared image from NASA’s Spitzer Space Telescope shows the broken Comet skimming along a trail of debris left during its multiple trips around the sun. On the lower right lies the Ring Nebula, coincidentally in the same direction as the cometary fragment.

Despite speculation that Comet 73P/Schwassmann-Wachmann 3 will strike the Earth on May 25, neither the main comet nor any of its more than 40 fragments pose a danger to Earth.

“We are very well acquainted with the trajectory of Comet 73P Schwassmann-Wachmann 3,” said Donald Yeomans, manager of NASA’s Near-Earth Object Program Office. “There is absolutely no danger to people on the ground or the inhabitants of the International Space Station, as the main body of the object and any pieces from the breakup will pass many millions of miles beyond the Earth.”

However, you can see the comet falling apart right before your very eyes, thanks to NASA’s Hubble Space Telescope, Swift X-Ray and Spitzer Space Telescope.

Click on the Space Rocks page for an animated preview of the next large comet impact.

14 May 2006 by Astronomy Environment Rocket Science

See Spot Run

The newly-spawned “Red Spot Jr.” Jovian storm system appears that it will overtake “Big Red” in early July. Note the “significant climate change” reference in the article.

From New Scientist:

Hubble watches Jupiter’s ‘Red Spot Races’

Hubble has sent back the clearest pictures yet of Jupiter’s new red spot.

The storm, dubbed “Red Spot Junior” is roughly half the diameter of the Great Red Spot, a huge storm that has churned away on Jupiter for at least 400 years – when humans first started observing the gas giant planet.

On 8 April 2006, the Hubble Space Telescope’s Advanced Camera for Surveys took new pictures of the baby storm, which was initially known as White Oval BA before it changed to the same salmon hue as the Great Red Spot (see “Jupiter opens a second red eye”) . The storm formed when three white oval storms merged between 1998 and 2000. Those white storms existed for about 60 years.

Image – NASA – Hubble photos of (top) Jupiter and (bottom) Red Jr.

The red colouring could come from material brought up from deeper within Jupiter’s atmosphere and then altered by the Sun’s radiation. If this is indeed what is happening, it may be a sign that the storm is intensifying.

The newly released images may give weight to the idea that Jupiter is in the middle of significant climate change. Temperatures at some latitudes could be changing by over 5°C, scientists suggest.

Another link to climate is that Red Spot Jr is forming at a latitude of 34° south. Theory has it that this is the where the transfer of heat from the equator to the pole grinds to a halt.

Hmmmmm. It must be all them Jovian SUVs trucking around beneath the clouds causing this colossal climate change.

Update: NASA’s Astronomy Picture of the Day has a nice close up picture showing Jupiter and both red spots.

04 May 2006 by Astronomy Environment Rocket Science

ACE in the Sky

Although extremely rare, auroras are occasionally seen in Southern California. I can recall a time when I saw the red glow in the northern sky from Palos Verdes Peninsula.

A space probe called Advanced Composition Explorer (ACE), measures attributes of the solar wind. ACE is useful to forecast (short term – an hour or so) fluctuations in the solar wind that may cause power-grid outages and extraordinary auroras under the right conditions. SpaceWeather.com points out that there are no plans to replace this resource when it ceases to function. From SpaceWeather.com:

COMMENTS, PLEASE: NASA’s ACE spacecraft is almost four years past its intended lifetime. Although ACE measurements of the solar wind flowing past Earth are crucial to space weather forecasts, there is no plan to replace ACE when the craft ceases to function. NOAA is seeking public comment on this state of affairs. If you enjoy auroras, please let them know that ACE needs a successor.

The ACE Caltech Website has this additional information about ACE:

From a vantage point approximately 1/100 of the distance from the Earth to the Sun ACE performs measurements over a wide range of energy and nuclear mass, under all solar wind flow conditions and during both large and small particle events including solar flares. ACE provides near-real-time solar wind information over short time periods. When reporting space weather ACE can provide an advance warning (about one hour) of geomagnetic storms that can overload power grids, disrupt communications on Earth, and present a hazard to astronauts.

ACE orbits the [Lagrange] L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth and 148.5 million km from the Sun. With a semi-major axis of approximately 200,000 km the elliptical orbit affords ACE a prime view of the Sun and the galactic regions beyond. The spacecraft has enough propellant on board to maintain an orbit at L1 until ~2019.

25 Apr 2006 by Astronomy Rocket Science

George – the Sixth Naked-Eye Planet

If you’re up early on April 17 through 19th and skies where you live are clear, don’t miss this opportunity to see “George,” the sixth naked-eye planet!

From NASA:

NASA – Venus Meets a Planet Named George

April 11, 2006: Ancient people didn’t have TV or electric lights. So, when the sun went down every night, they got their entertainment by watching the sky. And it was entertaining. Without city lights to interfere, the Milky Way was spectacular. Meteors flitted across the sky. Zodiacal lights chased the sunset.

Right: Voyager 2 took this picture of Uranus in 1986.

Of special interest were the five naked-eye planets, the ones you could see without a telescope. (The ancients didn’t have telescopes, either.) Countless hours were spent watching Mercury, Venus, Mars, Jupiter and Saturn, whose movements were thought to control the affairs of men.
Would you believe, in spite of all that watching, they missed one? There is a sixth planet you can see without a telescope, a planet named George.

“George” is not as bright as the others, but it is there, glowing like an aqua-blue star of 6th magnitude. It measures four times wider than Earth, has more than 30 moons and a dozen or so thin rings. George goes around the sun every 84 years, always spinning on its side as if something knocked it over.

George is better known as Uranus.

[ . . . ]

On April 17th, 18th and 19th, Venus and Uranus are going to have a close encounter in the dawn sky. Simply look east before sunrise. As a guidepost, Venus can’t be beat. It is so bright, people often think it’s a landing airplane. Simply scan Venus with a pair of binoculars (or a small telescope) and you’ll see Uranus right beside it. If the sky is very dark, you may be able to lift your eyes from the optics and see Uranus directly.

[read more]

12 Apr 2006 by Astronomy

Check out Today’s Eclipse

NASA Shared this video of the solar eclipse today from Turkey. Check it out!

NASA Shares Solar Eclipse With the World
NASA gave people a front row seat to today’s total solar eclipse, thanks to a partnership with the University of California at Berkeley and the Exploratorium. A streaming webcast brought the eclipse — visible along a path from South America to Africa to Asia — to schools and museums and computer desktops worldwide.

VIEW ECLIPSE VIDEOS: + Windows | + Real

The eclipse coverage was part of Sun-Earth Day, celebrated every year to help everyone better understand how our sun interacts with the Earth and other planets in the solar system. This year’s theme, “Eclipse: In a Different Light” shows how eclipses have inspired people to observe and understand the Sun-Earth-Moon system.

29 Mar 2006 by Astronomy Environment Science

Mars Spirit Rover Struggles Toward McCool Hill

Both Mars rovers have far exceeded their “warranty” and despite setbacks from time to time, have bounced back to carry on with their extended missions. The Spirit rover is currently limping (backwards, on five out of six wheels) toward it’s winter resting place atop a hill named “McCool.”

From Jet Propulsion Labs:

Mars Exploration Rover Mission: The Mission

Spirit Continues Driving on Five Wheels:

Spirit continued to make progress toward “McCool Hill” despite a reduction in solar energy and problems with the right front wheel. The team plans to have the rover spend the winter on the hill’s north-facing slopes, where the tilt toward the sun would help maximize daily output by the solar panels. On Spirit’s 779th sol, or Martian day (March 13, 2006), the drive actuator on the right front wheel stalled during a turn to adjust the position of the rover’s antennas. The stall ended the day’s drive, which brought Spirit 29 meters (95 feet) closer to McCool, still approximately 120 meters (390 feet) away.

Engineers conducted tests on sols 781 and 782 (March 15 and 16, 2006) on a testbed at the Jet Propulsion Laboratory as well as remotely on Spirit. Further analysis is needed to determine what caused the right front actuator to stop working. Meanwhile, the operations team has successfully commanded Spirit to drive using only 5 wheels. Engineers plan to have Spirit continue driving backward with five healthy wheels while dragging the right front wheel.

17 Mar 2006 by Aerospace Astronomy Rocket Science

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