How to spot the bright Comet NEOWISE using mobile apps
By
Chris Vaughan
Published Jul 22, 2020 4:49 PM EDT
Skywatchers the world over are buzzing about Comet C/2020 F3 (NEOWISE), the first easily-visible comet to appear in years. Your favorite mobile astronomy app can tell you if the comet is visible from your location, and where and when to look for it.
To see the comet, you will need clear skies to the northwest, and a very low horizon that is free of obstructing trees and buildings. If you live in an apartment with western or north-facing windows or a balcony, you're in luck, too.
You can see this comet with your unaided eyes, but it will become truly spectacular through binoculars and telescopes. What you should expect to see is a small, bright, fuzzy spot, possibly with an orange or green hue.
Binoculars will reveal the comet's faint tail extending generally upwards, away from the sun. Actually, look for two tails pointed in slightly different directions — a brighter one composed of debris the comet is dropping behind it and a fainter, blue-tinted one composed of ionized gas. The latter tail will always point directly away from the sun, since it is being pushed by the solar wind. While your telescope will magnify the comet's head nicely, its tail will extend beyond your telescope's limited field of view.
As comets swing through the solar system, we see them move with respect to the background stars — night-to-night, and even hour-by-hour. This comet, which originated in the distant Oort cloud of icy bodies that envelopes our sun, dropped into the inner solar system from below (or south of) the plane of the planets' orbits. On July 3, it passed through that plane as it rounded the sun just outside the orbit of Mercury.
Now the comet is swinging upwards (north of that plane) while it flies away from the sun. That trajectory will bring the comet closest to the Earth (or perigee) on Wednesday (July 22) at approximately 9 p.m. EDT (0100 GMT on July 23), when it will be 64 million miles (103.5 million kilometers), or 0.692 astronomical units (1 AU is the average distance between Earth and the sun) away from us.
After dusk during July, comet C/2020 F3 (NEOWISE) will be visible low in the northwestern sky as it travels northwest in the sky below the constellation of Ursa Major. Mobile apps can help you find it. This chart shows the comet's path through the sky until mid-August, at 11 p.m. local time. Each night the comet will diminish in brightness — so look for it as soon as possible. (Image credit: SkySafari app)
Unfortunately, as the comet nears Earth and looms larger, it will also be experiencing less heating from the sun, causing it to fade in visual brightness due to less gas production. It's a trade-off that makes looking at the comet at the first opportunity your safest bet.
Click here to continue reading on SPACE.com.
Report a Typo
News / Astronomy
How to spot the bright Comet NEOWISE using mobile apps
By Chris Vaughan
Published Jul 22, 2020 4:49 PM EDT
Partner Content
Skywatchers the world over are buzzing about Comet C/2020 F3 (NEOWISE), the first easily-visible comet to appear in years. Your favorite mobile astronomy app can tell you if the comet is visible from your location, and where and when to look for it.
To see the comet, you will need clear skies to the northwest, and a very low horizon that is free of obstructing trees and buildings. If you live in an apartment with western or north-facing windows or a balcony, you're in luck, too.
You can see this comet with your unaided eyes, but it will become truly spectacular through binoculars and telescopes. What you should expect to see is a small, bright, fuzzy spot, possibly with an orange or green hue.
Binoculars will reveal the comet's faint tail extending generally upwards, away from the sun. Actually, look for two tails pointed in slightly different directions — a brighter one composed of debris the comet is dropping behind it and a fainter, blue-tinted one composed of ionized gas. The latter tail will always point directly away from the sun, since it is being pushed by the solar wind. While your telescope will magnify the comet's head nicely, its tail will extend beyond your telescope's limited field of view.
How comet NEOWISE moves
As comets swing through the solar system, we see them move with respect to the background stars — night-to-night, and even hour-by-hour. This comet, which originated in the distant Oort cloud of icy bodies that envelopes our sun, dropped into the inner solar system from below (or south of) the plane of the planets' orbits. On July 3, it passed through that plane as it rounded the sun just outside the orbit of Mercury.
Now the comet is swinging upwards (north of that plane) while it flies away from the sun. That trajectory will bring the comet closest to the Earth (or perigee) on Wednesday (July 22) at approximately 9 p.m. EDT (0100 GMT on July 23), when it will be 64 million miles (103.5 million kilometers), or 0.692 astronomical units (1 AU is the average distance between Earth and the sun) away from us.
After dusk during July, comet C/2020 F3 (NEOWISE) will be visible low in the northwestern sky as it travels northwest in the sky below the constellation of Ursa Major. Mobile apps can help you find it. This chart shows the comet's path through the sky until mid-August, at 11 p.m. local time. Each night the comet will diminish in brightness — so look for it as soon as possible. (Image credit: SkySafari app)
Unfortunately, as the comet nears Earth and looms larger, it will also be experiencing less heating from the sun, causing it to fade in visual brightness due to less gas production. It's a trade-off that makes looking at the comet at the first opportunity your safest bet.
Click here to continue reading on SPACE.com.
Report a Typo