Human-Friendly Mosquito Attractant

I know its not astronomy or physics, but when you live out in the country, this type of breakthrough holds great importance!  Those clever biochemists have discovered an attractant that mosquitos love, but isn’t absolutely foul to the human nose. YAY!  Right now, mosquitos are everywhere.  It certainly doesn’t help that we have a nice sized pond in our back yard, but they’ve been especially bad lately.  I can’t wait for this stuff to hit the market!

The synthetic mixture, containing compounds trimethylamine and nonanal in low doses, is just as enticing to Culex mosquitoes as the current attractants, Leal said, but this one is odorless to humans.

Check out the rest of the story at ScienceDaily.com
No More Big Stink: Scent Lures Mosquitoes, But Humans Can’t Smell It

Living With A Star

Think that astronomy is pretty cool, but not very useful in everyday living? Think again! By investigating our closest stellar neighbor, the Sun, we have been amazed at the variety of ways in which it affects our planet. Certainly, the Sun is the source of all light and heat here on Earth, but there are many types of energy other than just light emitted by the Sun. The Solar Wind is a stream of charged particles that flows away from the Sun at speeds typically around 400 km/s. This solar wind, though, is not just a steady breeze, it can become quite gusty. Eruptions on the surface of the Sun throw enormous amount of material out into the solar system. Some of these eruptions, called coronal mass ejections (CMEs), are directed toward Earth at speeds upwards of 1000 km/s. The charges particles that flow from these eruptions can become entrapped in the Earth’s magnetic field and funneled onto our poles and are responsible for the Northern Lights. These spacebourne storms are becoming of interest not just to those who enjoy the Northern Lights, but also to telecomm companies who rely upon satellites for their business. These satellites can be damaged during strong solar storms and so now space weather forecasting is becoming just as important as the forecasting of Earthly weather.

Now, thanks to the Living With a Star program, there are a multitude of spacecraft out there monitoring and reporting back on the Sun’s activity with more probes on the way. There’s a great article about a few probes from this program that are in the works that will give us even better understanding of solar dynamics and how our star can affect us here on the Earth. Check it out! The article is called Living With A Star and is at the Science@NASA website.

I’m not dead yet!

Reports of the demise of Ulysses have been slightly exaggerated. The bird still lives!! It must be admitted, that its living on a day-to-day basis. It was expected that by July 1st, the hydrazine fuel would have frozen in the lines, and the spacecraft would begin to tumble. To stave this off, the flight engineers have been using small alternating bursts from the thrusters to maintain a trickle flow of fuel through the line. This is not unlike the practice of leaving your faucet to run slowly to keep your water pipes from freezing in the winter time. Same concept. Apparently, the trickle trick has been working! Here’s the latest from Nigel Angold, Ulysses Mission Ops Manager:

Dear Ulysses friends and colleagues,

As you are aware, the proposed July 1st Ulysses operations end date
has come and gone. And as a result of our fuel bleeding and other
operations strategies, we have managed to avoid freezing the
hydrazine so far!

Now we are continuing operations on a day-to-day basis until the
fuel freezes. That includes fuel bleeding every 2 hours to keep the
hydrazine moving through the pipes and Earth-pointing manoeuvres
interleaved, when required.

When we see the fuel freezing, we will switch off the S-band and
some instruments for a couple of days in an effort to thaw the
hydrazine. After that, we’ll try to switch on the X-band once again
using some more radical (and hence more risky) procedures.

If the fuel has not frozen by the end of July, we’ll try some benign
X-band switching in early August and plan for radical switching in
late August.

What will happen in the unlikely event that we re-establish our
X-band downlink? Well, obviously we’ll leave it on!!! And at the end
of August we should have enough fuel remaining to continue for a
number of months (assuming that we stop the fuel bleeding). The
short portion of pipe that is currently close to freezing will warm
up but other areas of pipework will cool down and they will get
close to freezing during the last quarter of 2008. As for funding
for operations beyond August, that’s another question.

This coming weekend, we will be testing the redundant on-board
receiver which is connected to the front low gain antenna (LGA-F).
This is to validate our ability to command the spacecraft when the
HGA is not pointing towards Earth e.g. if no manoeuvres have been
performed for several days due to frozen fuel.

I know some of the instrument teams have held wakes to celebrate the
fantastic journey that we have been on all these years. However, I
make no apology for the fact that Ulysses is not dead yet. I hope
that in the coming weeks we get to see the transition from fast to
slow solar wind.

Very best regards,
Nigel

All of this reminds me of that scene from Monty Python and the Holy Grail.

Ulysses Eulogy

Its was like watching someone turn off the life-support machines of an old friend. June 30th, 2008, was the last day of mission operations for the Ulysses spacecraft, after nearly 18 years of service. It also brings to an end the exploration of a region of our solar system that’s not likely to be visited again in our lifetimes.

The Ulysses Mission was originally conceived as the International Solar Polar Mission, a tandem mission with one spacecraft being built by NASA and the other by ESA. Budget cuts reduced the mission to a single spacecraft jointly engineered by the two agencies. Ulysses was originally to be launched in 1983, but was delayed to the Spring of 1986 and set to deploy from the cargo bay of the Space Shuttle Challenger. As a result of the Challenger accident, its launch was delayed even more. These delays would come back to haunt the mission as the radioisotope thermoelectric generators (RTGs) used to power the mission have a fixed lifetime and were constructed and tested in the early 80s. Ulysses was finally launched and deployed from the cargo bay of the Space Shuttle Discovery on October 6th, 1990 and began is trek out to Jupiter and to the Sun’s polar regions.

The primary 6-year mission called for a single solar orbit giving coverage of both the Sun’s southern and northern polar regions at solar minimum and covering radial distances from its perihelion of 1.3 AU to its aphelion of 5.4 AU. Ulysses performed so well that its mission would be extended multiple times allowing it to complete three full orbits. The additional orbits allowed Ulysses to investigate the polar regions during solar maximum, and during our current rise to maximum.

Eventually, the old RTGs became a terminal factor for the spacecraft. With power from the RTGs dwindling, power sharing techniques had to be employed. Various power sharing schemes were developed, but the one that was used allowed all of the science missions to remain active, however it required that the high-bandwidth X-band transmitter be shut down during data collection. Data was to be stored on board for later download. To retrieve data, the science instruments would be shut down and the transmitter restarted. However, the X-band transmitter never came back to life. This was not a stopper for the recovery of science data. The S-band transmitter used for command and telemetry could be used to stream the science data if at a slower rate, but the heat generated by the X-band transmitter was used to help keep the hydrazine fuel lines from freezing. With its power ebbing, its heaters off, and the X-band transmitter broken, Ulysses was destined to freeze and begin to tumble. Once it tumbles and loses lock on the Earth, recovery is impossible. It was determined that July 1st, 2008 would be the day that Ulysses was put to rest.

Since 1999, I’ve been working with the energetic particle data from the MF Spectrum Analyzer (MFSA) of the Heliosphere Instrument for Spectra, Composition and Anisotropies at Low Energy (HISCALE). Here the term “low energy” is relative. The HISCALE instrument measured protons and ions with energies from around 50 keV/nuc to upwards of 20 MeV/nuc and electrons from about 40 to 400 keV. The MFSA worked within the energy range of 50 to 5000 keV/nuc for protons, but provided a higher degree of energy resolution than anything else out there. Even though the spacecraft is now silent and adrift, we still have one and a half solar cycles worth of high-quality data that can yield a LOT of science.

Our immediate project at Fundamental Technologies is to organize and describe the data we have in such a way that it can be easily shared through the Virtual Heliospheric Observatory. If you’d like to use the HISCALE data or are just curious as to what we do at FunTech, browse over to http://ulysses.ftecs.com/ where I keep a blog on the current state of a few of our projects.