Spaceflightnow Mission Status Center: Venus Express

http://spaceflightnow.com/venusexpress/status.html

--- Although a new launch date has not been set, liftoff is expected to be targeted for sometime between November 6 and 9. ---

Russian space officials Monday set a Nov. 9 blastoff.

http://www.space.com/missionlaunches/ap_05...usexp_updt.html

Rakhir

Strange news.

The postpone of the launch was due to contamination problem in the faring. Now, according to the news from space.com :

Russian space officials Monday set a Nov. 9 blastoff for a European probe to explore Venus after its earlier launch was postponed because of a booster rocket problem.

Is it of another story?

Rodolfo

By "booster rocket", they are talking about the launch vehicle. The fairing whose thermal insulation contaminated VE is part of the booster rocket.

Rakhir

Roll Out to Launch Pad

http://sci.esa.int/science-e/www/object/in...fobjectid=38214

Rakhir

Pre-launch sequence was executed.
2 days...

http://sci.esa.int/science-e/www/object/in...fobjectid=38218

Rakhir

Interesting article:

'Venus Mission May Hold Surprises For Scientists And Public, Says CU Prof'
http://www.colorado.edu/news/releases/2005/421.html

If Venus is almost exactly like Earth, but much hotter, and Mars is quite a lot like Earth, but much cooler, and Venus is closer to the sun than Earth, and Mars is further away from the sun than Earth, then hmm, what could it be I wonder...

I'm looking forward to this mission myself..

Mars is only about 11% the mass of the Earth, and the bulk composition is quite different, so the differences abound. Given that and other differences that began with formation, I'd say differences should be expected as the rule and similarities seen as more surprising.

Venus has similar mass and bulk composition, but the essential cause-of-it-all difference maker may be the slow rotation. Because of that, no magnetic field. Because of that, the upper atmosphere is pounded by solar wind. Because of that, H2O is broken up and lost. Because of that, CO2 fills the atmosphere AND lighter rock (granite) is not formed. Because of the CO2, the stifling heat. Because of the lack of granite and the heat, entirely different crustal cycling regimes.

It's unclear if that is really the chain of causality, and certainly more exploration is needed, but it would be stirring if such a small matter led to such a huge difference. And it would still be unclear why the rotation is so slow; there is a chicken-and-egg question about whether or not drag in the massive atmosphere may have controlled the rotation rate. The other external factor that may have contributed is the absence of a large satellite.

Besides, the other intrigating thing is that Venus sluggishly rotates on its axis once every 243 Earth days, while it orbits the Sun every 225 days - its day is longer than its year!

On the other hand, Venus rotates retrograde, or "backwards," spinning in the opposite direction of its orbit around the Sun. From its surface, the Sun would seem to rise in the west and set in the east.

The other odd thing is that its Equatorial Inclination to Orbit is 177.3 degrees. By comparison, it is: 7.56 x Earth. That is its north pole is almost pointing to the south pole.

These are at least one of the oddies things that I would like to understand:

Why does the day is longer than a year?
Why the planet rotates on backwards?

Rodolfo

A whomping big celestial impact is my guess.

Interesting but...why no a moon. After an impact to Venus and that should have a moon like the Earth's case.

I thought that the Venus' slow rotation might be caused by a very heavy atmosphere that circulates the planet in the opposite side to its rotation.

Or perhaps that is a normal for physics' law since its neigboor planet Mercury rotates around 58 Earth days and orbits around the Sun 88 Earth days. That is more or less a very long day that approach to a "planet of close one year" for both Mercury (less days) and Venus (more days).

Rodolfo

Actually, should a large impact create a moon? My guess is that if Venus did get hit by something massive and powerful enough to practically flip it over, slow down its spin rate, and have it rotate in the opposite direction of most other major worlds, Venus was lucky enough to have survived intact, forget having a moon in the outcome.

Or maybe Venus was hit BY its own moon.

Moons tend to orbit their parent planet in the same direction as the planets rotation - so were a moon to colide with its parent planet, the likely impact would be an increase in rotation I'd have thought.

Perhaps it's a symptom of planet formation closer to the centre of the protoplanetary disk - further out from the sun, the local gravity from chunks of whatever is the major force, but closer in, the suns gravity is dominant.

It's a complex process, that's for sure.


Doug

There are good sources on the Net for things being wildly speculated about here.

To pick just one: the angular momentum of a planet-moon system would remain the same after an impact as before. Such a collision couldn't make the system go backwards unless it was going backwards in the first place.

For the Moon to be created from a collision, it had to be a glancing blow. A straight-on punch would not liberate a lot of material.

A collision would be necessary if Venus's rotation was set in place as its formation concluded. But there are suggestions that tidal and thermal dynamics of its massive atmosphere may have "set" the rotation at the current rate. If so, the initial rotation is irrelevant/unknowable. In fact, the low inclination suggests that there is some sort of sun-driven factor: a collision that reordered Venus's rotation radically would be unlikely to leave the axis so nearly perpendicular to its orbit -- although that kind of coincidence is not impossible.

The rotation is only one oddity, not two or more. Given that the rotation is so slow, the reversal is not so odd -- the difference between rotating slowly E-W or slowly W-E is not nearly so big a difference as the slow rotation in the first place. Consider that a point on Venus's equator is rotating at about the speed of a fast *walk*!!! If it were moving the other direction, but just as slowly, that would only be a difference of a few km/h.

Also, the relative relationship between the day and year of Venus is not an "extra" oddity. Given the slow rotation, that follows as a logical consequence.

There is a second mystery regarding Venus's rotation, however, and that is why it is [almost] synchronized so as to show [almost] the same face towards the Earth at every conjunction. Mathematically, it would seem impossible for the tidal attraction to make this happen... but if this is a coincidence, it is a remarkable one.

I'm filing this gem right next to the thermal energy in the Tiger stripes of Enceladus.

One thing is clear: The Solar System loves to throw us curve balls.

Well, as Chesterton said, the most remarkable thing about coincidences is that occasionally they DO occur. The classic one in the Solar System is the disks of the Moon and Sun being virtually the same size as seen from Earth, which is the only thing that makes solar eclipses as we know them possible.

The trouble comes when the fact that the human (and presumably animal) mind is designed to specifically look for patterns leads us to jump to the conclusion that a genuine coincidence is more than that. Arthur Koestler once wrote an infamous crank philosophical book based on precisely that logical fallacy.

Anyway, at the beginning of the planetary formation, all planets is formed orbiting around the sun in the counter-clockwise, all have the same plane inclination with respect to the sun, all planets has their axis in perpendicular position to the planetary plane and all rotate the same way as it is orbiting around the sun, it is counter-clockwise.

are those all above suppositions affirmative or not?

Rodolfo

There was this guy a long time ago named Aristarchus who wildly speculated that Earth went around the Sun and that the stars were other suns very far away.

The powers that be of his era accused him of religious impiety. His ideas were effectively buried for 1,500 years.

These ideas may "just" be speculation, but they are not wild. Uranus has been thought by many sober, rational astronomers to be in its present state due to major collisions by natural objects in its past, so why not for Venus to explain its current different state?

Less than one hour from launch!

Live webcast should be here:
http://www.starsem.com

Alternative link for the live webcast of the launch: ESA's Venus Express Site

Anybody getting a feed from here yet?

Just wondering if the error message I'm getting is because it hasn't starting or if there is an incompatibilty with the OSX version of Media Player.

James

The live feed won't start until 03:28 GMT, at least on the ESA site. I assume it is the same on the Starsem site.

Ah, cross posting, a much more useful site.

Starts only 5 mins before launch...

Both webcasts are working now although you get better resolution from the Starsem site.

0327 GMT (10:27 p.m. EDT Tues.)

The Venus Express flight director in mission control has given the final "go" for launch.

T - 40 seconds!!

Starsem still doesn't work for me bu thankfully the ESA feed does (thanks Waspie_Dwarf!)

LIFTOFF!!!!

OK through booster sep...

0336 GMT (10:36 p.m. EDT Tues.)

T+plus 3 minutes. The first stage strap-on boosters have been jettisoned. The second stage core is still running as planned. All system parameters are reported normal.

Fairing sep, third stage ignition...

Cutoff of 3rd stage and separation of nose module.

Third stage cutoff!

0342 GMT (10:42 p.m. EDT Tues.)

T+plus 9 minutes. The third stage motor has completed its firing and dropped away. The Fregat upper stage now must perform a brief firing to achieve an initial parking orbit around Earth.

There goes the feed. Oh well..guess I'll have to rely on the Spaceflightnow updates.

0348 GMT (10:48 p.m. EDT Tues.)

T+plus 15 minutes. ESA says the first Fregat burn has been successful. The vehicle is now coasting in Earth orbit for more than an hour before the upper stage is re-started to propel the spacecraft to Venus.

Argh! Is that second Fregat burn happening or not?

Fregat burn should be underway by now.

No word on Spaceflightnow yet...

EDIT: cross posting with you Emily. I feel your pain, I don't know how much more page reloads my computer (and me) can take!

From Spaceflightnow.com

0514 GMT (12:14 a.m. EST)

T+plus 1 hour, 41 minutes. By this point in the flight the Fregat should have completed its burn and then released Venus Express. We're awaiting confirmation from ESA that these events have occurred successfully.

From http://sci.esa.int/science-e/www/object/in...fobjectid=38243

Fregat second stage has successfully fired and place Venus Express to an escape trajectory

In other words Spaceflight Now doesn't know if the Fregat has worked either. The anticipation is killing me.

From http://sci.esa.int/science-e/www/object/in...fobjectid=38243

MET: +01h 40m
Fregat second stage has successfully fired and place Venus Express to an escape trajectory

Rakhir

EDIT : You were 1 min quicker than me Bricktop.

That's put me out of my misery.

Hurrrah!

Venus here we come

This from Daniel Fischer: "Just to report that Venus Express has phoned home exactly on time at 5:30 UTC through ESA's ground station in New Norcia, Western Australia! Everything seems to be going exactly to plan since 2 hours. Now it's about 3 weeks of spacecraft and instrument checkout; perhaps some nice pictures of Earth will be taken during that period (as ESA's Gerhard Schwehm just told me). Then it's quiet cruising (no science on the way), until Venus Orbit Insertion on April 11, 2006."

What I meant was, sometimes the answer is in the FAQ.

MET: +02h 40m
Sun acquisiton and successfully deployment of solar arrays confirmed

http://sci.esa.int/science-e/www/object/in...fobjectid=38243

Rakhir

And Public won't see any data till August.


Ya ya I know I'm bad.

"Sun acquisiton and successfully deployment of solar arrays confirmed "

------------------ YEEEEHAAWWWWWW! ------------------------------------

Chances of "Loss-of-Mission" have dropped by some 85%