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RASC Calgary Centre - Current Astronomical Highlights by Don Hladiuk

Follow Don on: ("astrogeo")

ASTRONOMICAL HIGHLIGHTS provides information about space science events for the upcoming month. The information here is a rough transcript of information covered on the popular CBC Radio One Calgary Eyeopener segment on 1010 AM and 99.1 FM usually on the first or second Monday of each month at 7:36 AM. Don is a life member of the Royal Astronomical Society of Canada and was twice President of the Calgary Centre. Since June 1984, Don has had a regular radio column on the Eyeopener describing monthly Astronomical Highlights to southern Albertans.

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ASTRONOMICAL HIGHLIGHTS February 2021

Broadcast Date February 1, 2021

Mars Mission Update

Last month, I mentioned one of the highlights to look forward to in 2021 was the arrival of a small fleet of at the .

These three Mars missions are from three different space agencies and they all arrive at Mars in February 2021.

1) February 9 – Mars Orbit Insertion. The United Arab Emirates have sent an orbiting spacecraft called Hope to study the weather and climate of Mars. This is UAE’s first Mars mission.

2) February 10 – Mars Orbit Insertion. China has launched an ambitious mission that consists of three spacecraft. An orbiter, a and a rover. The combined spacecraft stack will first orbit Mars and confirm a safe landing site for their Mars lander and rover. Landing to occur a few months after orbit insertion. This is China’s first Mars mission.

3) February 18 – . NASA is sending a rover called to look for signs of early life near an ancient delta. The Rover will also deploy a small helicopter called . This test article will see if it can fly in the thin Martian and provide valuable information from above. Perseverance also has the ability to drill core samples and store them in small tubes that can be picked up later and returned to Earth by another rover. One of the scientists who will decide if a sample is to be considered for the sample return mission is Dr Chris Herd from the University of Alberta.

Our family and other Albertans will be watching intently on February 18 as the NASA called Perseverance endures the “7 minutes of terror” associated with Entry, Descent and Landing (or EDL). Over 143,000 Canadians submitted their names as part of NASA’s “Send Your Name to Mars” campaign. In total 10.9 million names from around the globe were placed on three silicon discs that are attached to the deck of the rover.

What to look for on February 18:

At about 1:38 p.m. MST, (10 minutes before entering the Martian atmosphere), the spacecraft will jettison the cruise stage that helped fly Perseverance and Ingenuity to Mars. As the spacecraft enters the Martian atmosphere around 1:48 p.m. MST, the produced drastically slows the down, but these forces also heat it up dramatically.

Peak heating occurs about 75 seconds after atmospheric entry, when the temperature at the external surface of the will reach about 1,300 degrees Celsius. About three minutes later, Perseverance’s is expected to deploy with the help of a new technique called Range Trigger.

The parachute, which is 21.5 meters in diameter, deploys about 1:52 p.m. MST, at an altitude of 11 kilometers and at a velocity of about 1,500 kph. Twenty seconds after parachute deployment, the heat shield separates and drops away, revealing a and cameras that feed into the other new landing technology, called Terrain-Relative Navigation. Terrain-Relative Navigation is a kind of autopilot that can quickly figure out the spacecraft’s location over the Martian surface and select the best reachable safe landing target.

At the time the powered descent vehicle (combination of the descent stage and the rover) separates from the back shell it is only 2.1 kilometers above the surface.

The eight throttleable on the descent stage, called Mars landing engines, not only help the spacecraft fly to a safe landing site, but also help slow the spacecraft. When the powered descent phase begins, the spacecraft is traveling at about 306 kph 2,100 meters above the ground. It slows to 2.7 kph by the time it’s about 20 meters above the surface.

This illustration shows the events that occur in the final minutes of the nearly seven-month journey that NASA’s Perseverance rover takes to Mars. Hundreds of critical events must execute perfectly and exactly on time for the rover to land on Mars safely on Feb. 18, 2021. Credits: NASA/JPL-Caltech

When the descent stage determines it is 20 meters over the landing area designated by Terrain-Relative Navigation, it initiates the sky crane maneuver: Nylon cords spool out to lower the rover 7.6 meters below the descent stage. When the spacecraft senses the rover has touched down in Jezero Crater, pyrotechnically fired blades sever the cords, and the descent stage flies a safe distance away before impacting the Martian surface.

Follow the Landing Events on February 18

There are many ways one can follow the nail-biting events leading up to the landing on Mars. Here is a link showing many of the options. https://mars.nasa.gov/mars2020/timeline/landing/watch-online/

If you live in the Calgary area, NASA-TV is streamed on Channel 718 on the Telus Optik TV service.

Fascinating Landing Site

Perseverance will land in Jezero Crater at approximately 1:55 p.m. MST, located on the western edge of Isidis Planitia, a giant impact basin just north of the Martian equator. Perseverance's core goal is astrobiological (to seek signs of ancient microbial life) and the rover will be landing in a place with high potential for finding these signs. Western Isidis presents some of the oldest and most scientifically interesting landscapes Mars has to offer. Mission scientists believe the 45- kilometer crater was home to a lake about 3.5 billion years ago as well as to an ancient river delta (the word “Jezero” in several Slavic languages means “lake”). Together, they could have collected and preserved ancient organic molecules and other potential signs of microbial life from the water and sediments that flowed into the crater billions of years ago.

This illustration shows Jezero Crater — the landing site of the Mars 2020 Perseverance rover — as it may have looked billions of years ago on Mars, when it was a lake. An inlet and outlet are also visible on either side of the lake. CREDIT NASA/JPL-Caltech

Jezero Crater’s ancient lake-delta system offers many promising sampling targets. Parts of Jezero may be especially rich in carbonates, minerals that, on Earth, can preserve fossilized signs of ancient life and can be associated with biological processes. And new landing technologies will allow Perseverance to touch down even closer to the most promising locations than any Mars mission before it.

Another image of Jezero Crater on Mars, the landing site for NASA's Mars 2020 mission. It was taken by instruments on NASA's Mars Reconnaissance Orbiter (MRO), which regularly takes images of potential landing sites for future missions.

On ancient Mars, water carved channels and transported sediments to form fans and deltas within lake basins. Examination of spectral data acquired from orbit show that some of these sediments have minerals that indicate chemical alteration by water. Here in Jezero Crater delta, sediments contain clays and carbonates (shown in green). Credit: NASA/JPL-Caltech/MSSS/JHU-APL

Sounds from Mars

I have found having a radio column has its challenges when trying to share the latest discoveries by the Hubble Space Telescope or from the surface of another world. Well, for the first time, I hope to share some of the sounds from Mars. When NASA’s Perseverance rover lands on the Red Planet on Feb. 18, 2021, it will not only collect stunning images and rock samples; the data it returns may also include some recorded sounds from Mars.

The rover carries a pair of microphones, which – if all goes as planned – will provide interesting and historic audio of the arrival and landing at Mars, along with sounds of the rover at work and of wind and other ambient noise.

The way many things sound on Earth would be slightly different on the Red Planet. That’s because the Martian atmosphere is only 1% as dense as Earth’s atmosphere at the surface and has a different makeup than ours, which affects sound emission and propagation. But the discrepancy between sounds on Earth and Mars would be much less dramatic than, for example, someone’s voice before and after inhaling helium from a balloon.

The first sounds may be beamed back to Earth and available for the public to hear within days of landing, with a more processed version released about a week after that. The team will process the sounds, with the help of audio experts, to more clearly hear the most interesting sounds.

Apollo 14 – 50th Anniversary

I remember watching the Apollo 14 mission back in 1971. It was the first mission after the Apollo 13 accident and featured Alan B. Shepard (first American to enter space) as the commander. February 5th marks the 50th anniversary of the third successful landing on the ’s surface by two astronauts. On February 6th, it will be 50 years since a golf ball was played on the moon.

The Apollo 14 crew consisted of Alan B. Shepard Jr., Commander, Edgar D. Mitchell, Lunar Module Pilot, Stuart A. Roosa, Command Module Pilot. The command module was named Kitty Hawk and the lunar module was called Antares.

Mission Highlights

Apollo 14 launched at 2:03 p.m. MST on January 31, 1971.

Astronaut Alan B. Shepard Jr., Apollo 14 commander, assembles a double core tube as he stands beside the rickshaw-type portable workbench or modularized equipment transporter (MET) unique to this mission.

The photograph was taken by astronaut Edgar D. Mitchell, lunar module pilot, standing some 170 meters northeast of the Lunar Module (LM), during the mission's second extravehicular activity (EVA) on Feb. 6, 1971.

On Feb. 5, Antares made the most precise landing to date, approximately 26.5 metres from the targeted landing point.

Due to communications system problems, the first period of extra vehicular activity, or EVA, began almost one hour later than scheduled with Commander Alan Shepard setting foot on the lunar surface on February 5. This first EVA included deployment of a science station on the lunar surface and lasted 4 hours, 49 minutes.

The second EVA on Feb. 6 began when the LM egress hatch was opened at 2:15 a.m. MST. During this EVA, Shepard and Edgar Mitchell moved about a kilometre from their LM, conducting selenological investigations, collecting samples and attempting to reach the rim of Cone crater. NASA personnel monitoring the EVA estimate that the two astronauts were within 50 to 75 meters of the crater rim when they were advised by mission control to collect samples at that spot and begin their traverse back to the LM. The second EVA lasted 4 hours, 35 minutes, resulting in a new mark for EVA time by a lunar landing crew: 9 hours, 24 minutes. Shepard set a new distance-traveled record on the lunar surface of approximately 2743 metres. During the two traverses, the astronauts collected about 43 kilograms of rocks and regolith for return to Earth.

Orbital science activities were conducted by Stuart Roosa during the lunar surface activities period. He experienced some difficulties with the high-resolution, motion-compensating Hycon Lunar Topographic Camera while attempting to photograph the Descartes area, the landing site planned for .

The liftoff of Antares from the lunar surface took place precisely on schedule. Rendezvous and docking occurred only 2 minutes later than scheduled. The command module Kitty Hawk splashed down safely in the Pacific Ocean at 2:05 p.m. MST Feb. 9, exactly 9 days and 2 minutes after launch

What’s Up in the February Sky

Planets

Jupiter and passed behind the in late January and will re-emerge in the morning sky later in February. Mars shines high in the southern sky after sunset in the constellation Aries. rises just before the sun in bright twilight and reaches superior conjunction (passes behind the sun) in late March.

Artificial Satellites

The International (ISS) will be visible over Alberta in the evening sky for the first few days of February. The orbiting laboratory reappears in the morning sky around February 20. Look for a bright, slow moving star-like object generally moving in a west to east direction. For future dates and times for ISS passes over Alberta, go to this website and enter your location (important to change your location from the default): https://heavens-above.com/

Another website for ISS passes is operated by NASA: https://spotthestation.nasa.gov/sightings/index.cfm

Dates to Remember

Feb. 01: 18th Anniversary Columbia Accident Feb. 03: 55th Anniversary of the first by Luna 9 in 1966 Feb. 05: 50th Anniversary Apollo 14 Moon Landing Feb. 06: 50th Anniversary of Alan Shepard’s golf shot on the Moon Feb. 07: Spring Equinox on Mars Feb. 09: UAE’s Mars orbiter “Hope” enter Mars orbit Feb. 10: China’s Tianwen Mars Probe enters Mars orbit Feb. 12: Chinese New Year – Year of the Ox Feb. 14: resupply mission launches to the ISS Feb. 18: Mars Perseverance Rover is scheduled to land on Mars at ~13:55 MST Feb. 18: Free public astronomy lecture – for more information go to: https://calgary.rasc.ca/speakers2021.htm#febGM Feb. 18: Mars 4 degrees above the moon Feb. 20: cargo carrier launches to the ISS on an Antares rocket Feb. 20: Parker Solar Probe makes 4th Venus Flyby Feb. 21: Perijove #32. For more information go to: https://www.nasa.gov/mission_pages/juno/main/index.html Feb. 27: Full Moon at 1:17 am MST Feb. 28: Planet Mars below Pleiades star cluster

Follow Don on Twitter at: https://twitter.com/astrogeo

For more astronomy info go to: The Calgary RASC website

February 2021 Sky Chart Set for February 15 – 20:00 MST

Sky Chart courtesy of Heavens-Above.com

Don will be back in March 2021

Previous Astronomical Highlights:

• January 2021 • December 2020 • November 2020 • October 2020 • September 2020 • August 2020 • July_2020 • June_2020 • May 2020 • April 2020 • March 2020 • February 2020

Other Sources of Current Sky Information:

• Monthly Star Charts for the Calgary Area • Calgary RASC Monthly Events Calendar • Calgary Weather - from Environment Canada • Heavens-Above Main Page (for Calgary) - ISS passes, Iridium Flares and Satellites visible from Calgary • Dark Sky - generate a monthly calendar of Moon phases, Sunset/Sunrise, Moonset/Moonrise, hours of darkness etc. • Sky News - the Canadian astronomy magazine. • Astronomy Magazine • Sky and Telescope Magazine • Skymaps.com - download and print a monthly Evening Sky Map and Calendar • Astronomy Picture of the Day • Comets currently visible • SkyHound - Current Observing Information • NASA JPL Space Calendar