Shuttle fleet grounded once again
The Associated Press is reporting that NASA has grounded further shuttle launches pending an investigation of how foam insulation once again broke off from Discovery’s fuel tank during lift-off. Also of concern is a 1.5-inch long piece of tile lost from Discovery’s underbelly, near the landing gear. Although review of video taken during launch and docking with the ISS and scans conducted with a laser-tipped crane onboard has revealed no damage that may hinder the current mission’s return to Earth, NASA’s schedule is to be put on hold until the problems can be resolved.
Shuttle program manager Bill Parsons spoke to reporters Wednesday evening, describing the matter at hand. He said:
‘Until we’re ready, we won’t go fly again. I don’t know when that might be, so I’ll just state that right up front. We’re just in the beginning of this process of understanding.’
One can only hope that this understanding will soon be attained to speed our safe return to space.
STS-114 and Science on the ISS
Space Shuttle Discovery succesfully launched from NASA’s Kennedy Space Center on Cape Canaveral this morning at 10:39 EDT. This marks NASA’s first shuttle mission since the loss of Columbia in 2003, hence its designation as the “Return to Flight.”
STS-114 will be primarily a resupply mission to the International Space Station, carrying a new gyroscope to replace a malfunctioning one on the ISS as well as a stowage platform for the Quest airlock to aid in future spacewalks. The astronauts will also be testing out various new repair techniques on several sections of test ceramic tiles in the shuttle payload bay, to see if structural damage like that suffered by Columbia can be repaired during a shuttle mission.
NASA’s human spaceflight is often criticized by scientists as a money pit that diverts funds from scientifically useful projects such as interplanetary probes and data-collecting satellites. The amount of science conducted by the human spaceflight program has significantly decreased since the Columbia accident. Since Russia’s Soyuz and Progress resupply vehicle carry much less payload than the Shuttle, NASA and her sister agencies decided to reduce the permanent crew aboard the ISS to two shortly after the Columbia accident. Science aboard the ISS has always been dependent upon having a large crew, since day-to-day maintenance operations require at least two astronauts. Therefore, the successful return to flight status of the space shuttle is crucial to useful science being conducted aboard the ISS. While critics often cite the lack of science being conducted on the ISS as a reason to cut its funding, it is worthwhile to note that sustained or increased funding could drastically increase the amount of science being conducted on the station by reducing the time until the station reaches its full capacity (probably six) of astronauts and cosmonauts.
Possible evidence of life on Titan
There is some speculation that there is life on Titan, Saturn’s largest moon. The source of this speculation is Chris McKay of NASA’s Ames Research Center and Heather Smith of the International Space University in France.
Titan’s atmosphere is about 5% methane, and Dr. McKay thinks that it could be due to methanogens — strict anaerobes that produce methane as a byproduct of their cellular metabolism. These methanogens would breathe hydrogen from Titan’s atmosphere, and consume organic molecules descending from Titan’s atmosphere as food. The three substances considered as a food source were ethane, tholins, and the most promising, acetylene which yields six time the energy per mole as either ethane or tholins.
Whether or not methanogens exist on Titan remains to be seen. The proof will be when the raw Huygens data is re-analyzed to determine the levels of hydrogen on the surface of the moon. If they are 1/1000th the levels that they are in the atmosphere, there’s a very good chance that there are methanogens present because no known non-biological process would be able to explain the low hydrogen levels. The data has already been collected, all that remains is separating the hydrogen levels out of the rest of the data from when the probe descended to Titan’s surface. If analyzing the hydrogen levels proves too difficult, the team might try to measure the acetylene levels instead, because they too would show a fall off towards the surface:
One hope for testing their idea rests with the data from an instrument on Huygens called the GCMS, which recorded Titan’s chemical make-up as the probe descended. It will take time to analyse the raw data, partly because hydrogen’s signal will have to be separated from those of other molecules. “Eventually, I hope, we will have numbers for at least upper limits for hydrogen,” says Hasso Niemann of Goddard Space Flight Center in Maryland, principal investigator of the GCMS.
Acetylene could be easier to analyse, McKay says, and it too might betray life. “I would guess that there would be a similar fall-off of acetylene if the microbes are eating it.”
Meteor showers, Mars satellites, and shuttle launches
A smattering of space and astonomy news tonight…
After scrubbing the scheduled Discovery launch, NASA plans to go ahead with the launch on Tuesday, assuming there are no problems.
Shuttle program manager Bill Parsons said the only way to thoroughly check the system is to fuel Discovery and have all its equipment running.
“We believe the best way to go through this is to do a countdown,” he said. “If the sensors (gauges) work exactly like we think they will, then we’ll launch on that day. If anything goes not per the plan that we’ve laid out in front of us, then we’ll have a scrub and we’ll have to talk about it.”
This will be the first shuttle mission in two years, since the Columbia tragedy.
The Mars Reconnaissance Orbiter (MRO) is scheduled to embark on its six-month journey on August 10, blasting off from Cape Canaveral. The MRO is special for a few reasons:
- It’s huge: 4 stories by 2 stories; 2180Kg.
- It will glide 20% closer to the planet, at an average height of 305Km from the surface.
- It will take pictures over an area 10x larger than previous surveys.
- It will be able to transmit 10x the amount of information per minute than any other Mars probe. (I wonder what the actual data rate will be?)
There are six instruments on board:
- The High Resolution Imaging Science Experiment which will snap pictures that can resolve objects as small as an office desk* over 1% of the entire Martian surface.
- The Context Camera which takes wide-angle images
- The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) which will be able to identify minerals over an area as small as a swimming pool.**
- The Shallow Radar (SHARAD) will measure the atmosphere’s water vapor, dust, and temperature with twice the sensitivity of previous probes
- The Mars Color Imager will track daily weather changes***
- Another (unnamed) instrument to make future landings safer by finding Mars’s two moons (Phobos and Deimos) based on their predicted missions so future landers can use their gravity to land closer to their targets
Click for a larger image of the MRO (4.22MB).
* 1 office desk is a new SI unit recently developed by NASA. It is equal to 1/20th of a swimming pool.
**1 swimming pool is another SI unit developed by NASA. It is equal to 20 office desks.
***No word on whether weathermen on Mars will suck too.
Mars will join the Perseid Meteor Shower on August 12 before sunrise.
The planet with three suns
If HD 188753 Ab were inhabitable, there would probably be some fantastically expensive beachfront real estate available for sale, of for no other reason than the planet experiences triple sunsets on occasion. Located in the Cygnus constellation, the planet was discovered by Dr. Konacki of Caltech using the Keck I telescope. Alas, the planet is a hot gas giant, and thus will not be explored by Spaceman Spiff.
What is interesting about the find is the light that it sheds on planet-formation. This planet exists in the most gravitationally-complex solar system yet found. The triple sunset would be a rare occurence.
“Multiple-star systems have not been popular planet-hunting grounds,” said Konacki. “They are difficult to observe and were believed to be inhospitable to planets.”
The new planet belongs to a common class of extrasolar planets called “hot Jupiters,” which are gas giants that zip closely around their parent stars. In this case, the planet whips every 3.3 days around a star that is circled every 25.7 years by a pirouetting pair of stars locked in a 156-day orbit.
The existence of this particular arrangement of stars and planet calls into questions astronomers’ understanding of how hot gas giants actually form.
The circus-like trio of stars is a cramped bunch, fitting into the same amount of space as the distance between Saturn and our Sun. Such tight living quarters throw theories of hot Jupiter formation into question. Astronomers had thought that hot Jupiters formed far away from their parent stars, before migrating inward.
“In this close-knit system, there would be no room at the outskirts of the parent star system for a planet to grow,” said Konacki.
Hot Jupiters are believed to form out of thick disks, or “doughnuts,” of material that swirl around the outer fringes of young stars. The disk material clumps together to form a solid core, then pulls gas onto it. Eventually, the gas giant drifts inward. The discovery of a world under three suns contradicts this scenario. HD 188753 would have sported a truncated disk in its youth, due to the disruptive presence of its stellar companions. That leaves no room for HD 188753’s planet to form, and raises a host of new questions.
The masses of the three stars in HD 188753 system range from two-thirds to about the same mass as our Sun. The planet is slightly more massive than Jupiter.
Oh well. Maybe it has a moon with some nice beachfront property…
Photographing abandoned Apollo relics and the new lunar base
NASA has plans to return to the moon, beginning with the Lunar Reconnaissance Orbiter (LROC), which will, among other things, finally lay to rest the ridiculous conspiracy theories surrounding the moon landings. Those skeptical of the moon landing have often asked why the remains of the lunar landing have never been photographed by a telescope like Hubble. The answer is quite simply because Hubble cannot photograph objects smaller than 60 meters wide on the moon. The largest of the Apollo program remains is 9 meters.
But LROC, scheduled for launch in 2008, will be able to photograph everything left behind from the Apollo missions, and it will also map the terrain of the moon in preparation for a return to the lunar surface. NASA plans to return to the moon no later than 2020. By using long-term analysis of shadows from photos taken at various times of the year, scientists intend analyze the shapes and locations of both the terrain and Apollo remains to a greater degree than they could doing just a single pass. Even the tracks from Rover may be visible.
The main mission for the LROC is to survey and laser-map the entire lunar surface that astronauts may be exploring to find such features as old, hardened lava tubes which could be used as shelter in case of a solar storm, and water ice. Specifically, NASA would like to know whether or not the polar regions of the moon are more habitable for astronauts. The thought is that some higher ridges might constantly be in the sunlight while their shadowed areas might harbor ice which could be used for drinking water.
Never before has the lunar surface been analyzed as closely as it will be in the coming years.
There’s a Mars hoax?
According to the NASA science webpage, there’s a Mars hoax where many people mistakenly believe that Mars is approaching the Earth so closely that it will be as bright as the full moon.
There’s a rumor going around. You might have heard it at a 4th of July BBQ or family get-together. More likely you’ve read it on the Internet. It goes like this:
“The Red Planet is about to be spectacular.”
“Earth is catching up with Mars [for] the closest approach between the two planets in recorded history.”
“On August 27th … Mars will look as large as the full moon.”
And finally, “NO ONE ALIVE TODAY WILL EVER SEE THIS AGAIN.”
I must confess that I’ve not heard or read this. But I don’t get many forwarded emails, and I don’t hang out with many people that believe everything they read on the Internet.
In any event, Mars could never approach Earth so closely with no consequences for those living on Earth. This would be plastered all over the news if it were to happen: the tide alone would be all sorts of messed up. The moon creates the tides, and Mars is much more massive than the moon. Consequently, we would be having extreme tides unlike anything ever seen on Earth at any point in its history if Mars were to get that close. And it would play havoc with Earth’s orbit around the sun (and also likely also the rotation of the Earth on its axis).
So what is the truth?
The truth is that Mars will be converging with Earth on October 13 to a distance of 69 million kilometers. This isn’t even the closest that the two planets have been: in August of 2003, the Earth and Mars were 56 million kilometers apart. Nonetheless, the results of this convergence will be just as spectacular as it was two years ago:
Sixty-nine million km is good. At that distance, Mars shines brighter than anything else in the sky except the Sun, the Moon and Venus. The visual magnitude of Mars on Oct. 30, 2005, will be -2.3. Even inattentive sky watchers will notice it, rising at sundown and soaring overhead at midnight.