3I/ATLAS CLOSEST APPROACH TO EARTH: Interstellar comet 3I/ATLAS makes its closest approach to Earth on Dec. 19th, passing 270 million kilometers away. That's not very close. Nevertheless, experienced amateur astronomers will be able to take beautiful pictures of the 11th-magnitude comet as it passes our planet and heads back out of the Solar System. Look for it in the constellation Leo and submit your images here.
MARS AND VENUS ARE CONVERGING NEAR THE SUN: Are you looking for Mars or Venus? Don't! You will hurt your eyes. The two planets are very close to the sun, converging for a rare double solar conjunction. This coronagraph image from SOHO shows the two worlds on Dec. 17th with Mars in front of star cluster NGC 6530 at the same time.
Click here to set the scene in motion
Mars and Venus are moving in opposite directions, swapping places in the heavens. On Jan. 6th (17:00 UTC), Venus will pass behind the sun moving right to left. On Jan. 9th (09:59 UT), Mars will pass behind the sun moving left to right. Weeks after they cross paths, Mars will become a naked-eye morning planet, while Venus becomes the brilliant "Evening Star."
When a planet passes behind the sun, astronomers call it a "superior solar conjunction." Mars and Venus are about to have consecutive solar conjunctions less than 3 days apart, making this a true Mars-Venus-sun alignment to kick off the New Year.
Realtime Space Weather Photo Gallery
Free: Spaceweather.com Newsletter
CHRISTMAS GIFTS FROM THE STRATOSPHERE: Christmas is coming. Are you looking for a far-out gift? Check out the Earth to Sky Store. It's filled with items that have visited the edge of space onboard cosmic ray research balloons:
Earth to Sky gifts have flown above 99.7% of Earth's atmosphere, experiencing space-like blasts of cosmic rays, extreme cold, and a wild ride parachuting back to Earth after the balloon explodes. Even Amazon doesn't carry items this far out.
Don't forget to enter coupon code "BLACKCAT" at checkout for a 10% holiday discount.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
Realtime Comet Photo Gallery
Free: Spaceweather.com Newsletter
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter