Astro Bob

  I won't let my words get in the way. Enjoy this spectacular, just-released video of Perseverance landing on Mars from the moment the parachute pops open to the blizzard of dust at touchdown. The first audio of fluttering Martian winds along with new still images have also been released. Don't forget to select the full-screen viewing option (open square at lower right) for the best view. In this single image from the video, notice there's no "fire" shooting out of the descent vehicle's thrusters. Illustrations show flames, but in reality, when liquid hydrazine burns it produces an invisible exhaust of nitrogen and hydrogen. NASA / JPL-Caltech You can also listen to the first audio from the Red Planet! New view of the Perseverance rover in Jezero Crater. NASA / JPL-Caltech In this view you can see two of the rover's wheels and a variety of rocks including "light" rocks and holey ones. NASA / JPL-Caltech This image shows how the area around the ro...

  The Big Dipper and some green auroral "fire" from a minor (G1) geomagnetic storm in September 2018. Bob King I was going to wait to write about the northern lights because they were originally forecast for Saturday night, Feb. 20. That just changed with the most recent NOAA space weather forecast . A minor geomagnetic storm may occur tonight (Friday, Feb. 19-20) instead between about 9 p.m. and midnight CST. As with so many auroras, times change so I would be on the lookout anytime between now and dawn.  The cause is a familiar one — a high-speed wind of electrons and protons streaming from a gap in the sun's magnetic canopy called a coronal hole. Earlier this evening, conditions were excellent for auroras across northern Europe. Let's cross our fingers they repeat over North America tonight. The moon is half and shouldn't put out too much light.  The Mars Reconnaissance Orbiter captured this photo of the capsule containing the descent vehicle and Perseverance ...

Members of NASA’s Perseverance Mars rover team watch in mission control as the first images arrive moments after the spacecraft successfully touched down on Mars, Thursday, Feb. 18, 2021. Besides looking for past Martian life, the rover study local geology and become the first mission to collect and cache Martian rock and soil. NASA / Bill Ingalls Nice work! The success of today's mission reverberated across the country, offering cheery relief from the drumbeat of COVID-19. At the same time the powered descent vehicle lowered the rover to the Martian surface, my friend Sam carefully lowered himself down an icy waterfall on a frozen creek. Although our icy hike precluded watching the landing, I kept careful track of the time so I could follow those seven dicey minutes in my imagination.   Isn't this just classic Mars? This is the first photo sent back from Perseverance moments after landing on Thursday, Feb. 18, 2021. NASA Perseverance sent back two black and white images of a ...

Watch for the return of the youthful crescent tonight. The moon will be just 1.2 days (about 29 hours) old. You'll need a wide open view to the southwest to see it best. Stellarium Even if you're already young, I still encourage you to check out the moon tonight (Feb. 12). For the rest of us, seeing the childlike moon may recall the vigor and innocence of youth. Every month at dusk the crescent returns, reminding us that each lunation is a fresh opportunity to start again. Begin a project we've put off. Throw out useless documents. Cook something exotic. This is a 1.5-day-old evening crescent from September 2020. Bob King Look for the dainty crescent about a half-hour after sunset. Click here for your sunset time. You'll find the moon low in the west-southwest about 7° high, not quite a fist held at arm's length against the sky. For the Americas, only 1.5 to 1.8 percent of the moon will be illuminated by the sun, depending on your location. Eastern hemisphere obser...

Once you've found Mars, aim your binoculars at the bright planet, focus sharply and then star-hop down to Uranus. One Jan. 30, 5.5° separate the two planets, equal to one binocular field of view. I've marked their positions on two dates — Jan. 30 and Feb. 15. There are no stars of similar brightness near Uranus, so it should be easy to identify.  Stellarium with additions by the author Back on Jan. 20, Mars and Uranus were in conjunction just 1.6° apart, a fine time to use a bright planet to find a faint one. I wanted to share the news at the time but got caught up in other things. Soon after, the bright moon made finding Uranus difficult. Now that dark skies have returned, let's give it another shake. Starting Jan. 30, the moon rises after the end of evening twilight, providing the window of darkness we need. For the next few nights (Jan. 30 - Feb. 2) Mars shines within 5-7° of Uranus, close enough to star-hop from the brighter planet to the fainter with a pair of binocula...

NASA loaned the moon rock specimen 76015,143 that was put on display in the Oval Office this week. Its quiet presence belies a violent history. NASA  I was thrilled the other day to see a moon rock in President Biden's office. At the request of the Biden Administration, NASA loaned the moon rock in a special display case which now occupies a book shelf in the Oval Office. For the incoming administration it's a "symbolic recognition of earlier generations' ambitions and accomplishments, and support for America's current moon to Mars exploration approach," according to a NASA press release.  In a different Apollo moon rock the dark spots are glass-lined impact craters called zap pits surrounded by lighter rock chipped off during impact. NASA Apollo 17 moonwalkers Harrison Schmidt and Eugene Cernan chipped the sample from a large boulder at the base of a blocky mountain called the North Massif in the Taurus-Littrow Valley on Dec. 13, 1972. Designated as lunar sam...

Jupiter and Saturn are seen here on Jan. 8, 2021 in bright twilight about 50 minutes after sunset. They are currently 2° apart but appear more separated because I used a 200mm telephoto lens to magnify the scene so Saturn would show more clearly.  Bob King When was the last time you saw Jupiter and Saturn? Not since their great conjunction? You don't have much time left. The planet pair is quickly slipping into the twilight glare. As you can see from the photo I almost missed Saturn. Thank goodness for that gap in the trees! Although Jupiter was easy to spot despite its altitude of just 3° at the time I never found Saturn because — I hate to admit this — I forgot to bring binoculars.  The same way Jupiter and Saturn were in conjunction on Dec. 21, 2020, each planet will take its turn in conjunction with the sun. Saturn goes first on Jan. 24, followed 5 days later by Jupiter. Since they'll be in the same line of sight as our friendly star, the planets will be invisible for seve...