Wednesday, February 17, 2021

Mars Landing! And a Speculative Question: What Spot Would You Pick on Earth?

 

Courtesy of NASA

The landing is almost here (or by the time you read this, it's happened already, for better or worse)! I hope, hope, hope that all goes well. Mars is a tough target, and I've seen to many failures and disasters. But...if they are able to stick the landing, we'll have an incredible adventure ahead of us, exploring the Jezero Crater, the site of an ancient sea and river delta complex. It's thought to be one of the most likely places to find evidence of any life that might have evolved on Mars.

Jezero Crater delta complex, landing site of the Perseverance Mission

Lots of good resources and landing schedules can be found here: Landing Toolkit: Perseverance Rover - NASA Mars. I've checked out things ahead of the landing, as you can see below, and the rock samples look intriguing.

(You can do your own pic with the mission toolkit)

I'm curious. The Mars landing site was carefully chosen as to glean the most information possible in a small area. If you had a single chance to land a rover on Earth for an only exploration, what place on Earth would you pick for the landing? And why? Answer in comments!


Saturday, January 30, 2021

You Can See Yosemite Valley from the Tuolumne River! In a Manner of Speaking...

Those of you who know the layout of Yosemite National Park will also know that the title of today's post must come with some kind of caveat because any hiker or cartographer knows that the Tuolumne River in Yosemite National Park flows through a vast gorge the depth of the Grand Canyon (it's even called the Grand Canyon of the Tuolumne River). You just can't see the one valley from the other.

But...the Tuolumne River also flows across the flat plains of the Great Valley of California, and if we count "Yosemite Valley" as being also some of the significant peaks and cliffs that ring Yosemite Valley like Half Dome, El Capitan, and Sentinel Dome, you can in fact see the valley from the Tuolumne River.

This is not one of my occasional posts about the better-known spot for viewing Half Dome from Hall and Keyes Roads near Turlock. I get in enough internet trouble over that one, but it is indeed possible to see the very top of Half Dome and El Capitan from my daily walking trail along the Tuolumne River in Waterford. But the additional caveat is that it has to be a really clear day, and we have precious few of those over the course of year. Sometimes weeks can pass between sightings of any mountains at all. But following our huge storm this week, the air was crystal clear today.

The additional caveat is that you need binoculars or a good zoom lens to see the domes and cliffs. With the naked eye, the mountains are difficult to distinguish from one another. But on those rare clear days, and with the right equipment, and knowing where to look, you can indeed see some of Yosemite Valley's most famous landmarks. In a way of course it is frustrating. I'd rather be there than here, but chances will start increasing as the pandemic finally begins to subside.

If you are wondering about the cranes in the foreground, our 1964 vintage bridge is being replaced by a safer, wider bridge. The anchoring columns of the present bridge are unstable during floods; all bridges are perfectly safe, the engineers say, right up until they are not.

In any case, if you couldn't make out the various domes and cliffs and peaks in the opening picture, they are labeled below. 

If you live in the Central Valley (we call it the Great Valley) and wonder if you can see any particular Sierra peaks, check out caltopo.com and find the dropdown command for "simulated view". You can adjust the map for a view from anywhere covered by the program. Below is an example of the view I used to label the peaks shown in this post.




Wednesday, January 6, 2021

A Beautiful Scene for a Horrific Day

There aren't many days like this. That can be both a good thing and a bad thing. My country was rocked by a coup attempt and the Capitol Building was invaded and vandalized for the first time in centuries. It dominated my day and little else was accomplished, other than to stare unbelievingly at the screen where the events unfolded in Washington D.C. and various state capitols. When things settled somewhat, we had to get outside, away from the media. And we discovered it was one of the clearest days of the year.
We headed a few miles east to the single best viewpoint I know of in the western foothills of the Sierra Nevada: Turlock Lake State Recreation Area. The lake mainly serves as a fishing and boating site (as well as being a principle irrigation reservoir), but there is some interesting geology, and a wonderful view.

The dam is constructed on the sediments of the Turlock Lake and Mehrten formations, and a number of interesting fossils have been found in the area: mastodons, camels, horses, huge tortoises, and gigantic 9-foot-long tusked (really!) salmon.

East of the main picnic area there is a paved road that climbs to the top of the highest local hill, and on a clear day like this one was, the view extends from the high peaks of Yosemite National Park across the Central Valley to the mountains of the Diablo Range, and the rest of the Coast Ranges. Today was one of the clearest days I've seen in a long time.
Some lenticular clouds were building over the Sierra Crest, making me wish I was I could be up there and a little closer, but that wasn't to be this time. Maybe soon...
Postscript (1/30/21): Anonymous asked what peaks were visible in these pictures. I checked on caltopo.com and found that we were looking at the heart of the Yosemite high country. Here are the caltopo.com images for the last two views above. The first shows from left to right Mt. Simmons, MaClure, Lyell, and Clark.
The second shot shows Mt. Clark, Gray Peak, and Red Peak.