Showing posts with label space probe. Show all posts
Showing posts with label space probe. Show all posts

October 19 - Mariner 5 Flies by Venus!

  Posted on October 19, 2021


This is an update of my post published on October 19, 2010:





During the 1960s, there was a Space Race, with Cold War enemies Soviet Union and United States trying to outdo each other in exploring the solar system.

At first, the USSR pulled ahead by being the first to successfully launch a rocket into Earth orbit (Sputnik 1 – 1957) and then by being the first to put a man in space (Yuri Gagarin on Vostok 1 – 1961). A few months after each of these Soviet successes, the US was able to match the feats with Explorer 1 (1958) and Alan Shepherd in a Mercury spaceship (1961).


Many Americans would say, however, that the US won the Space Race because of the daring manned moon landings and explorations. To this date, this feat has not been matched by astronauts from any other country.

But, you ask, what does all of this have to do with Venus?

The Soviet Union and America's space program, NASA, chose a wide variety of projects, including exploring nearby planets, during the time of the Space Race. These planetary flights were all unmanned, and many of them did not succeed for one reason or another. Launch failures and loss of contact (in the latter case, the fate of the spacecraft is often unknown) happened with some regularity. However, when a mission worked, the data gathered by the spacecraft is beamed home and enriches the scientific knowledge for the entire world.


Here are some of the flights deemed failures:
1961 
USSR Sputnik 7
USSR Venera 1
1962 
US Mariner 1
USSR Sputnik 19
USSR Sputnik 20
USSR Sputnik 21
1963 
USSR Cosmos 21
1964 
USSR Venera 1964A
USSR Venera 1964B
USSR Cosmos 27
USSR Zond 1
1965 
USSR Venera 2
USSR Venera 3
USSR Cosmos 96
USSR Venera 1965A

And to offset all that failure during that four-year period:

1962 
US Mariner 2

Finally, in 1967, both nations met with success in exploring Earth's nearest planet. On October 18, 1967, the Soviet Venera 4 became the first probe to analyze another planet from its surface. And the very next day, October 19, 1967, the United States' Mariner 5 did a successful fly-by. Both spacecraft were able to send back important data that tells us a lot more about our “sister planet.”

Sister planet??? Umm...


Not only is Venus the closest planet to the Earth, it is the closest planet to ours in size. That is why it is called Earth's sister planet.

But it's not very much like Earth in some pretty crucial ways.

Here is a picture of what it might look like on Venus. It's really, really hot.


REALLY hot!

Like 900 degrees Fahrenheit! (500 degrees Celsius). That's hot enough to melt lead, zinc, and some alloys of aluminum!

Venus's atmosphere is 90 times thicker than Earth's, with thick clouds of sulfuric acid! Yikes!

But maybe future humans will colonize the atmosphere of this hellish planet and live there? Check out this outrageous sounding idea in this article.


Here are some photos we've pieced together from missions to Venus:






September 21 – Bye-bye, Galileo!

Posted on September 21, 2017

Today's historical anniversary is quite appropriate:

On this date in 2003, the spacecraft named Galileo ended its mission by entering Jupiter's atmosphere - to be crushed and to burn up.


Why did I say it was appropriate? Because this year (2017), on September 15 (about a week ago), the spacecraft named Cassini ended ITS mission by entering Saturn's atmosphere - to break apart and burn up.


These "death dives" were conceived to make sure that the planets' moons, which might possibly be homes to some primitive lifeforms, will not be contaminated with Earth organisms (bacteria, etc.). There is no way for the gas giants themselves to have any sort of life-as-we-know-it, and the extreme heat as the spacecraft burn up in the atmospheres would ensure that the remaining materials would be sterilized.

But the death dives are more than just a handy way to avoid contamination. These dives give us a bit more data to go along with all the data the probes already provided during their lifetimes. Scientists are pretty sure they know many aspects of the atmospheres and other conditions on the gas giants, and so they are able to make predictions of the conditions the spacecraft will encounter on their suicidal dives. The spacecraft keep transmitting until they break up, or are crushed, so we are able to compare the predictions with the actual measurements taken and with the behavior of the spacecraft. 

Here are some comparison stats of the two spacecraft:

Launch dates: 
Galileo - October 18, 1989
Cassini - October 15, 1997

Planned mission lengths, including travel time:
Galileo - a bit more than 8 years
Cassini - about 10 years

Actual mission lengths, including travel time:
Galileo - almost 14 years!
Cassini - almost 21 years!

Galileo lasted six years longer than planned, and Cassini lasted more than a full decade longer than planned! Wow!
   



Here are a few highlights of Galileo's findings: 

Discovered the first asteroid moon
First direct measurement of Jupiter's atmosphere
First asteroid flyby
Observed Comet Shoemaker-Levy 9's collision with Jupiter
Observed volcanoes erupting on Io (a moon)


Observed Io's interaction with Jupiter's atmosphere
Theory of liquid ocean under moon's ice supported (but not yet confirmed) - Europa
Probable liquid saltwater layers under moons' ice - Ganymede and Callisto


Magnetosphere detected on Ganymede
Exosphere detected around three large moons
Faint ring system detected around Jupiter



(I covered some of Cassini's findings here and here.)



December 25 - Anniversary of Space Probe Win AND Fail

Posted on December 25, 2016

Some people in the U.S. and world get to take off work and school on Christmas Day -- although lots of people don't! If you go to an amusement park like Disneyland on ChristmasDay, give huge smiles and greetings to everyone working there -- even the people singing and dancing in the parades and shows -- because you gotta know that many of them are missing some family festivities! If you eat out at a restaurant, or stay at a hotel, on Christmas Day be super nice to all the workers, for the same reason. And tip big! Tis the season of giving, ho ho ho!!

You know who else doesn't get to slack off on Christmas Day? The vehicles we send into space to take photos, make measurements, and collect all sorts of data for us.

But on this date in 2003, that's just what the space probe Beagle 2 did! 

The Beagle 2, a British Mars lander, had been successfully released by the European Space Agency's vehicle, the Mars Express, on December 19, 2003. It was about to land when -- Bam! -- it suddenly stopped transmitting. 

Scientists tried to contact it over and over again, but they never got a signal. Had the Beagle crashed onto the surface of Mars? Did it land softly but then tip over? Did major systems fail?

We didn't know for more than a decade. Finally, in 2015, NASA used its orbiting camera to spot the Beagle 2 on the surface of Mars. Scientists who studied the photos think that the Beagle landed just fine, but that two of its solar panels didn't open as planned, and so they remained in a position that blocked the communication antenna. 


This shows us once again that space exploration is hard. A grain of sand, a ray of high-energy radiation, a rock -- actually, almost anything -- could mean the difference between success and failure.

In this case, all the biology experiments the Beagle was supposed to perform didn't happen. A lot of money, time, creativity, and effort -- went for nothing!

Exactly one year later, another European Space Agency mission was successful when the ESA-built probe Huygens separated from the Cassini orbiter. Cassini was in orbit around distant Saturn, and Huygens's mission was to land on Saturn's moon Titan. Just a few weeks later, in 2005, Huygens "stuck" the landing! (Gymnastics term. It's a good thing!) 

Actually, Huygens is the very first spacecraft to land on a body in the outer solar system. Back in 2005, Huygens was then the farthest-away landing ever, and it still is the record-holder.

Check out the Virtual Reality Mars experience available at the Kennedy Space Center. 

This is Matt Damon in "The Martian."
But one day it could be YOU -
really on Mars!


Here is an animation of Huygens's landing on Titan. Also, I enjoyed this video on Europa and Titan. 

Wouldn't it be amazing to live with Saturn glowing in the sky?
This is an artist's version of what the Titan landscape might look like.
 
Also on this date:






Christmas birthdays














Christmas Pudding Day