A massive space rock wider than Manhattan, Asteroid 877 Alinda, made its closest approach to Earth on Wednesday, offering stargazers a once-in-a-decade opportunity for observation.
Astronomy enthusiasts need not worry if they missed the initial flyby, as Alinda will remain visible for several more days, according to the Virtual Telescope Project, which will hold a live stream of Alinda on Sunday, beginning at 12:30 p.m. ET.
The asteroid, discovered in 1918, passed within approximately 7.6 million miles of Earth on Wednesday.
Gianluca Masi, an astronomer with the Virtual Telescope Project, suggested that Sunday presents the optimal viewing conditions. “A similar event happens on average once a decade,” Masi noted in a Wednesday update.
For those eager to glimpse the asteroid, binoculars will be necessary. Alinda’s projected magnitude of 9.4 on Sunday falls short of naked-eye visibility. Masi recommends using 10×50 binoculars to get the best view.
Its next closest approach is predicted on Jan. 25, 2087, passing by within 15.46 million miles, according to spacereference.org, an online database cataloging asteroids and comets in space.
Not a Threat
Despite its massive size, estimated at 4.2 kilometers in diameter, Alinda poses no threat to Earth. Classified as a Near Earth Asteroid (NEA) by NASA’s Jet Propulsion Laboratory, it is not considered potentially hazardous.
Alinda’s orbit brings it close to Earth’s path without intersecting it. The asteroid completes a revolution around the sun every 3.89 years, with its distance from the sun ranging from 1.06 to 3.88 astronomical units, according to Space Reference.
Alinda also exhibits a slow rotation, completing one full turn on its axis every 28.41 hours.
The Virtual Telescope Project emphasized the significance of this asteroid’s near approach, stating that Alinda is among the five largest asteroids expected to come within 15 million kilometers of Earth from now until 2200.
Astronomers and space enthusiasts alike are encouraged to seize this rare opportunity to observe one of the largest near-Earth asteroids of the century. Viewers should search for asteroid 877 Alinda in the Orion and Gemini constellations, according to the project.
Space Reference says that Alinda is larger than 99 percent of asteroids.
It also shares similar orbits and characteristics with three other “Near Earth Objects,” 17 Thetis, 248 Lameia, and 329 Svea.
4 ‘Bright Planets’
Skywatchers in January also have other rare celestial events to watch for besides asteroids.
According to NASA, during January, stargazers will be able to “enjoy a sweeping view of four bright planets at once” during the evening. Skywatchers can spot Venus and Saturn in the southwest, Jupiter high overhead, and Mars in the east during the first few hours after dark.
From Jan. 17 to 18, sky watchers should watch for when Venus and Saturn will come into conjunction. NASA reports that “over a couple of weeks, the two planets come within just a couple of finger widths’ distance apart in the sky [about 2 degrees].”
Also, in January, Mars will reach opposition, meaning that the Red Planet “is directly opposite the Sun from Earth and shines brightly all night.”