Perseverance Rover

Much of the excitement has settled now that Mars 2020 Perseverance Rover is safely on the surface of Mars after the 18 Feb 2021 landing. I gathered images and links to a collection of things I feel tell the story of this rover in a not too complicated way. The mission is very challenging. A primary goal is to find evidence that microbial life may have existed on the Martian surface in the past.

Perseverance is undergoing system checks for the many sophisticated tools it carries while imaging the surroundings. Scientists are eager to begin moving the rover across the ground and to test the helicopter Ingenuity it carried under the chassis.

Touchdown in Jezero Crater

You might wonder where Perseverance landed and why is that place is important. Landing took place in Jezero Crater. The crater is about 49 km (30 mi) across. It is believed to have once been filled with water. This image shows a dried riverbed and delta of a water source that once flowed left-to-right and filled the crater. The colors are indicators of various types of mineral deposits and not actual colors. The rover landed in the lower right quadrant of this image just below the two side-by-side small craters on the flat plain and not far from the delta formation.

Ancient river delta into Jezero Crater | MRO | NASA

Show me more…

Comet C/2020 M3 (ATLAS)

Comet C/2020 M3 (ATLAS) was discovered on 27 June 2020. The acronym ATLAS stands for Asteroid Terrestrial-Impact Last Alert System, based on the Hawaiian islands. Two telescopes of the robotic early warning system are designed to detect smaller near-Earth objects a few weeks to days before they might impact Earth. Since 2017, the scopes survey one quarter of the observable sky four times each clear night. The system is NASA funded and operated by the University of Hawaii.

Orbits near the Earth of objects larger than 1 km are well-known. Most are well documented and predicted years in advance of their close approaches to Earth. Objects down to 140 meters in size are harder to see. It is estimated ⅓ of them have been found. None of those found so far are predicted to threaten Earth in the next century.

Smaller objects less than 140 meters are detected only when they are much closer to Earth. Late discovery means there is the greater potential for a locally catastrophic collision with little warning time if they are on a collision course. ATLAS looks for these smaller objects. Comet C/2020 M3 (ATLAS) was discovered by this system.

The comet became a popular object for amateur astronomers to image. By November 2020 it was nearing the Orion constellation. This image on 6 Nov 2020 was by José J. Chambó at his web site I thought it would be interesting to image this comet several times as it passed through Orion.

José Joaquín Chambó Bris

Show me more…

NASA Perseverance Mars Rover

Scientists and space enthusiasts are excited about the upcoming landing of the exploration rover Perseverance on the surface of Mars on 18 Feb 2021. The NASA-TV broadcast from Mission Control starts at 11:15 am PST/2:15 pm EST.

The mission is designed to look for bio-signatures in a river delta of an ancient lakebed. It will harvest rock-core samples for analysis and possible return to Earth in a future mission. The rover will be joined by a small helicopter to extend its vision and reach around the area. This video (< 3 min) shows the basics of the rover design and plans for the mission. You are invited to explore more about the mission at this link.

Perseverance helicopter being examined by NASA engineers

Perseverance was launched in July of 2020. It took 7 months to coast to this meeting with Mars. On a collision course, it will enter the thin atmosphere at over 12,000 mph. The challenge is how to safely slow the vehicle and land it. This following graphic illustrates the overall plan, but not to scale.

The fast-moving craft in coast phase enters the atmosphere at upper left. A heat shield protects it and slows it down from 12,000 to 950 mph. A parachute deploys and the heat shield falls away. The craft scans the terrain to find the landing site.

At 180 mph and 1.3 miles altitude, the parachute is detached letting the vehicle fall. Rocket engines control the descent and slow it down to less than 2 mph and 60 ft. above the surface. The rover is lowered about 20 ft more by cables to touchdown on the surface. The cables detach and the rocket assembly flies far out of the way.


Lowering of rover by cables for touchdown | NASA

The technique has been done before in 2012 when the Curiosity rover landed on Mars. It was described then as 7 minutes of terror. Mars is far from Earth. By the time radio signals reach us more than 11 minutes later, events will already have played out, successfully or not. All actions are programmed. Curiosity is still functioning well on Mars today. Here is a recent selfie.

How I Met the President

Recent events involving mobs and riots at our nation’s capitol and the extensive security precautions for the 2021 Inauguration reminded me of my opportunity to meet President Obama in 2012. It was during a campaign stop at the University of Iowa. I felt it would be interesting to share some of the behind-the-scenes activities involved in that visit.

“What’s your name?” asked President Obama.

“My name is Jim, Mr. President. It is an honor to meet you.” We stood close, arms around each others waists, and smiled for the official photographer. There was a flash of light.

“Thank you for your support and your hard work” he said.

“It is my pleasure, sir.” It was over and couldn’t have taken more than 30 seconds.

I had just met President Obama. I worked hard for his re-election in 2012. Countless phone calls, letters to the editor, weekly team meetings, 1-on-1 meetings, conversations with friends, and efforts to recruit volunteers. I finally got to meet the man. It was over literally in a flash. I wish I could have talked with him over a beer or two.

I read in a news story the week before that President Obama might stop in Iowa City. I sent the news clip to Matt, my regional campaign coordinator. By the weekend, it was confirmed. Things happened fast. Matt called me and said “I have a ticket for you to meet the President next week. What’s your social security number?” That’s when it really struck me. Something special was in the works.

Photos and commentary about the Presidential visit are below. There was much security as with all his visits. Our county is a strong Democratic stronghold in a largely rural state. He needed our continued support for his re-election.

Solar Panels | 2020 Report

Now that 2020 is over, we can report annual results from our home’s solar panels. Previous posts can be found at this link.

Panel production data is accessible via a phone app or the computer. Charts for monthly and daily production can be generated. Records from our electric utility show our home averages 400 kW-hr of energy per month to operate all the electrical devices, based on 15 yrs of data. Our panel output nearly reached that amount in the summer months thus offsetting our house needs. Winter months production was low due to low sun angle and more cloudy days.

Viewed on a daily output basis, variability is obvious due to seasonal and weather differences.

Show me more…