For astronomers, the two-week window around a close Mars approach is the best time for spotting surface features on the planet with a telescope, or for seeing the planet’s bright polar caps. People set up telescopes to catch a glimpse of the Comet C2023 A3 Tsuchinshan-Atlas in the night sky outside Vienna, Austria on Oct. 12, 2024.GEORG HOCHMUTH/Getty Images
So close and yet so far.
It’s an apt expression for the planet Mars these days. With the red planet moving in for its closest approach to Earth for the rest of this decade, NASA officials are wishing it could be just a little bit closer to aid in the retrieval of samples that a robotic rover has been gathering there.
Both stories have put Mars back in the headlines this week.
For Canadian sky watchers, the next several nights will be ideal for observing the planet, which gleams like a pale orange star when it rises in the eastern sky after sunset. Mars is officially at its closest on Sunday, when its distance from Earth will shrink to just more than 96 million kilometres away. But any night this month should be considered prime viewing time.
For many locations in North America, Monday night will bring the added spectacle of the full moon crossing directly in front of Mars.
Astronomers refer to this type of event as an “occultation” and it can be a fascinating experience to watch. This is especially true for those equipped with telescopes that are powerful enough to show the tiny rust-coloured disk of Mars slip behind the moon’s silver edge, and then reappear on the other side up to an hour or so later.
But even if viewed through binoculars or just by eye, the event is certain to be dramatic as the moon creeps closer and closer to the planet until Mars winks out completely.
Viewers in central and eastern Canada are best placed to witness this on Monday. The following table shows the occultation of Mars for selected cities. (Viewers on the west coast and in the far north will see the planet brush past the moon but not disappear behind it.)
How to use the moon and the Gemini Twins to find Mars during its closest approach to Earth, Jan. 12 to 14
Looking East 8 p.m. (All Canadian time zones)
Moon
Jan. 12
Castor
Pollux
Moon
Jan. 13
Mars
Moon
Jan. 14
Watch the full moon cross in front
of Mars on the night of Jan. 13
Local times for selected Canadian locations
MARS
DISAPPEARS
MARS
REAPPEARS
LOCATION
Calgary
Winnipeg
Windsor
Toronto
Montreal
Quebec City
Halifax
St. John's
7:29:04
8:18:35
9:12:15
9:17:33
9:25:31
9:30:04
10:38:57
11:28:34
7:42:47
9:05:20
10:23:06
10:28:45
10:36:39
10:40:07
11:53:49
12:35:43
THE GLOBE AND MAIL, SOURCE: THESKYLIVE.COM;
INTERNATIONAL OCCULTATION TIMING ASSOCIATION
How to use the moon and the Gemini Twins to find Mars during its closest approach to Earth, Jan. 12 to 14
Looking East 8 p.m. (All Canadian time zones)
Moon
Jan. 12
Castor
Pollux
Moon
Jan. 13
Mars
Moon
Jan. 14
Watch the full moon cross in front
of Mars on the night of Jan. 13
Local times for selected Canadian locations
MARS
DISAPPEARS
MARS
REAPPEARS
LOCATION
Calgary
Winnipeg
Windsor
Toronto
Montreal
Quebec City
Halifax
St. John's
7:29:04
8:18:35
9:12:15
9:17:33
9:25:31
9:30:04
10:38:57
11:28:34
7:42:47
9:05:20
10:23:06
10:28:45
10:36:39
10:40:07
11:53:49
12:35:43
THE GLOBE AND MAIL, SOURCE: THESKYLIVE.COM;
INTERNATIONAL OCCULTATION TIMING ASSOCIATION
How to use the moon and the Gemini Twins to find Mars during its closest approach to Earth, Jan. 12 to 14
Looking East 8 p.m. (All Canadian time zones)
Moon
Jan. 12
Castor
Pollux
Moon
Jan. 13
Mars
Moon
Jan. 14
Watch the full moon cross in front of Mars on the night of Jan. 13
Local times for selected Canadian locations
MARS
DISAPPEARS
MARS
REAPPEARS
MARS
DISAPPEARS
MARS
REAPPEARS
LOCATION
LOCATION
Calgary
Winnipeg
Windsor
Toronto
7:29:04
8:18:35
9:12:15
9:17:33
7:42:47
9:05:20
10:23:06
10:28:45
Montreal
Quebec City
Halifax
St. John's
9:25:31
9:30:04
10:38:57
11:28:34
10:36:39
10:40:07
11:53:49
12:35:43
THE GLOBE AND MAIL, SOURCE: THESKYLIVE.COM; INTERNATIONAL OCCULTATION TIMING ASSOCIATION
Mars itself is quite easy to find, even in brightly lit city skies. When the moon is not there to act as a moving pointer, you can look for two bright stars that are also found low in the eastern sky after dark and then rise higher later in the evening.
These are Castor and Pollux, the Gemini twins from Greek mythology and the two brightest stars in the constellation of the same name. But as brilliant as they are, they cannot outshine Mars this month.
Opportunities to see Mars at its best are relatively rare. They come up each time Earth overtakes Mars as the two planets orbit around the sun, roughly every 27 months. But close approaches of Mars are not all alike. Mars won’t be this close or look this good again until 2031.
For astronomers, the two-week window around a close Mars approach is the best time for spotting surface features on the planet with a telescope, or for seeing the planet’s bright polar caps.
Since the dawn of the space ages, these times also dictate when it is best to launch a spacecraft to Mars because they offer the shorter trips with the most payload and the least expenditure of fuel. Because it typically takes about nine months to reach Mars, the midpoint of the journey coincides with the closest approach.
As it happens, there are no missions currently heading for Mars, but plenty of action is underway on the planet’s surface. NASA’s Perseverance rover, which launched in 2020 (two close passes of Mars ago), has been operating on the planet’s surface since February, 2021. In that time, it has travelled more than 32 kilometres and collected 25 samples, each one sealed in a cigar-sized cylinder. The samples are meant to be returned to Earth for detailed laboratory analysis.
The scientific return would be immense, say researchers who are engaged with Perseverance’s day-to-day traversing across the Martian landscape. They include samples that would help pin down precisely when in the past water was flowing on Mars and the degree to which conditions may have been amenable for life.
“It would revolutionize our understanding of Mars if we were to get those samples back,” said Christopher Herd, a planetary scientist at the University of Alberta who is a member of the rover’s science team and holds the title of “sample shepherd” for the current leg of its mission.
The challenge is that, in the interim, the cost of the return mission has ballooned to US$11-billion with the samples unlikely to make it back until 2040. Last year, that caused NASA to pause on the effort and look for other options. On Tuesday, the outgoing NASA administrator and other senior officials held a teleconference to update reporters on their plans to streamline the sample return mission.
The upshot is that there are two pathways the agency intends to pursue, one is a redesigned mission developed internally, the other is to partner with a private company with “heavy lift” capability to hitch a ride to Mars and grab the samples.
Currently, that would put Elon Musk’s Space X and Jeff Bezos’s Blue Origin in the running for what would likely become the first-ever commercially supplied interplanetary trip. Both companies are in the midst of testing their heavy lift rockets with launches currently scheduled in the coming days.
These are not aiming for Mars at the moment. In the near term, the moon will be the more pressing target.
But plans are in the early stages and a key objective of the Tuesday briefing seemed to be to persuade the Trump administration to take up the cause and fund the effort to bring the samples back. With Mr. Musk playing the self-described role of “first buddy,” it may well be that Mars exploration will see a boost in the next few years.
For years, the agency has adopted “Moon to Mars” as the mantra for its human space exploration program. That goal remains aspirational. But in symbolic fashion this week, the night sky has lined up both destinations in one dazzling view to keep us looking up.