Wednesday, May 13, 2009

Hubble, Herschel, Planck

This is an exciting week for those of us taking interest in astronomy and astrophysics: Today, the Hubble Space Telescope has been grappled by the robotic arm of Space Shuttle Atlantis, to be checked and repaired over the next few days by NASA astronauts, and tomorrow, an Ariane 5 rocket is to lift into orbit the European satellites Herschel and Planck. Herschel is an infrared telescope, with the largest mirror so far in space, and Planck will take precision measurements of the cosmic microwave background. Both telescopes will be placed near Lagrange Point L2.

The Hubble Space Telescope grappled by the robotic arm of Space Shuttle Atlantis this afternoon, 13 May. (Credit: NASA TV via youtube.)

While we are fascinated by the data and photos gathered by space probes like Hubble or WMAP, it's easy to forget that the technology behind these missions is complex, and can fail. The service mission to Hubble had been postponed and temporarily cancelled in the wake of the Columbia disaster, and still now, Space Shuttle Endeavour is ready to lift off for rescue in case Atlantis gets in trouble. In February this year, NASA lost the Orbiting Carbon Observatory satellite following a rocket malfunction. The Ariane 5 rocket has failed completely twice in 43 launches, and missed to bring its payload in the right orbit on another two occasions.


Ariane 5 with Herschel and Planck, yesterday night (12-13 May) at the opening of the BAF (Bâtiment d'Assemblage Final) door before the transfer to the Launch Zone. (Credit: ESA/S. Corvaja, ESA@flickr.)

I was wondering why the decision had been taken by ESA to pack both Herschel and Planck on one rocket, putting both eggs in one basket. But it seems the Ariane is constructed to lift two satellites, launches are expensive, and so far, there is no need for commercial satellites to be parked at Lagrange Point L2.

So, I'll keep my fingers crossed tomorrow afternoon.


Update (14 May): ESA has set up a live web streaming of the Herschel-Planck launch starting at 14:40 CEST/12:20 UTC. The launch itself is scheduled to take place at 15:12 CEST/13:12 UTC.

Update (14 May, 16:00 CEST): Congratulations! All went well so far: Herschel and Planck have been detached from the carrier, and are sending signals. Now, to the Lagrange point. The transfer takes about two months.




9 comments:

Arun said...

From your lips to God's ear!

Georg said...

Der Mondberg-Uhu

Der Mondberg-Uhu hat ein Bein,
sein linkes Bein, im Sonnenschein.
Das rechte Bein jedoch des Vogels
bewohnt das Schattenreich des Kogels.

Bis hundertfunfzig Grad im Licht
gibt Herschel ihm (zwar Langley nicht),
im Dustern andrerseits desgleichen
dasselbe mit dem Minuszeichen.

Sein Wohl befiehlt ihm (man versteht),
dass er sich stetig ruckweis dreht.
Er funktioniert wie eine Uhr
und ist doch bloƟ ein Uhu nur.

Successful Researcher: How to Become One said...

Great post!

Uncle Al said...

First World civilization hovers at the edge of irrecoverable social, economic, and thermodynamic collapse. We placed perpetual markers of our apex beyond the reach of mudfooted politicians and mobs. If any future somebody comes to visit, may they appreciate what we were compared to what we are - before they succomb in kind to butchering the productive for feeding the reproductive.

Phil Warnell said...

Hi Stefan,

Thanks for the run down and reminder of all the presently occurring space activity. To be honest I can’t get enough of the stuff, as the roar of a rocket engine has my imagination soar more so then the thought of the LHC. Even though giving my age away in admitting first being hooked on space and it’s exploration since as a young boy first hearing the eerie beep that Sputnik broadcasted . In the early days I was more fascinated with the man missions, then only to later realize that unmanned (robotic) missions for the most part garner more science and are less costly. I am pleased then that Europe retreated from its initial plans an reason in developing the Ariane 5 rocket as the lift vehicle for mounting Hermes, which was to be Europe’s own version of a space shuttle.

I see you question why Europe would risk both telescopes being launched on one rocket. It’s probably because the Aiane 5 was commissioned and developed to be man flight capable that they consider it designed reliable enough to risk it. From my own perspective I find this mission to squeeze at best a few more years out of the aging Hubble telescope as more an unwarranted risk with minimum return. Like much of the American space program I feel it has more often to do with bravado then good science or wise use of resource.

In this regard I think I've mentioned before of how I agreed with Gerard t'Hooft when he spoke out at his Perometer lecture on this issue, where he contended we should first develop robotic technology better to be able to properly and firmly lay the foundations to facilitate later humanities eventual spreading further within the solar system. I guess there are many who still think as I did when much younger as how could one consider it space exploration without Buck Rogers:-)

Oh yes I wonder how many of your readers realize why besides Sir Fredrick Willaim Herschel being a famous (German born) English astronomer, why precisely this telescope was named in his honour?

Best,

Phil

robert said...

Yes, it's a great mission for ESA, I'm really glad that so far it went so well.

I had the same concern with 'alles auf eine Karte setzen" and understand now better after Phil's post. Thanks also for the background on Herschel, in that post. I hadn't yet gotten around to look it up on wikipedia.
So it seems one may pronounce his name
correctly both in the german or the english way. :-)

stefan said...

Hi Phil,


thanks for the reminder about Herschel and the infrared, I hadn't thought about it!

Actually, about the decision to launch both satellites with one rocket, I read some interesting remarks on the blog of a German journalist covering space science:

Ariane usally carries at least two satellites, and up to four, into geostationary orbits. In this case, as the target is the Lagrange point L2, there was no way in combining either Herschel or Planck with a commercial satellite, because the orbits are too different: yesterday's launch reaches apogee in a height of 1.200.000 km, versus 36.000 km for going geostationary. Apparently, two separate lauches on two Arianes would have been too expensive - the price tag for one Ariane launch is about 160 million Euro.

An alternative to the Ariane would have been using Russian Proton rockets for two separate launches, which seems to be about as expensive as one Ariane launch. However, ESA had decided early to use the Ariane ECA (I do not know when - but the argument that the Ariane originally was planned to lift a manned shuttle is a good one...), and the design details of both Herschel and Planck were then adapted to the capacity of the vast Ariane cargo bay. Planck wouldn't even fit anymore on a Proton rocket.

Speaking of prices, the cost of Herschel (including its share of the launch) is given by ESA as 1100 million Euro, and that of Planck as 700 million Euro.

I was a bit surprised by these tags - the sum is about half the cost of the LHC. But as for the LHC, it is shared by the ESA member states, and has been stretched over the years. Actually, Herschel has been conceived 25 years ago (then still as FIRST, the Far-Infrared and Submillimetre Space Telescope) - at about the same time when CERN started discussing the LHC!

Cheers, Stefan

Phil Warnell said...

Hi Stefan,

Thanks for all the additional information regarding the Ariane 5 launch. It takes me back to visiting Florida several years ago and so excited about visiting the then new facility where they have an entire Saturn 5 mounted out on its side, along with the original Mercury control room and other artefacts. I must say that my wife was very patient and understanding as I spent more the 4 hours in that building, for which later I thanked her for.

The truth is I could have spent days in the place. It’s a funny thing which I guess is the same for other’s, which is it’s one thing to read about, look at photos or video of such things and another to be right up close as to be able to touch them. Standing at the back of the rocket being dwarfed by just one of its engine nozzles gives one an appreciation; understanding and feeling one just can’t get otherwise. That could be the Saturn 5, the pyramids or the Grand Canyon for that matter. My only wish is that one day that perhaps my grandson might live in a world where he might board a vehicle or elevator to look upon the earth and the cosmos beyond which only a few have been so privileged thus far to have experienced.

Best,

Phil

Arun said...

Hubble and Shuttle transit the Sun