TradeTrade
Jump to any asset 873 assets, updated daily

Stock·NASDAQ·Communication Services

Iridium Communications Inc. (IRDM)

$44.91 -1.14 (-2.48%)
At close: Oct 30, 4:00 PM EDT
Hold
51 / 100
CleaRank Financial AI scorei
Market cap
$4.76B
Dividend yield
1.34%
Street target
$47.00median of 7 analysts
52-week range
$15.65 $57.18
01

IRDM stock forecast today

Where IRDM stands today, and what CleaRank Financial AI makes of it.

IRDM at a glance

Iridium Communications Inc. (IRDM): Hold, 51/100 on CleaRank's AI score.

  • Trend Mixed: the price is above its 200-day but below its 50-day moving average ($39.78 and $46.89).
  • Earnings IRDM beat estimates in 2 of its last 5 quarters, yet fell the next day after 1 of those beats.
  • Insiders Insiders sold $20.4M and bought $871K over the last 18 months.

Figures as of October 30, 2026.

CleaRank Financial AI

Iridium Communications Inc. (IRDM) carries a CleaRank rating of Hold and a model score of 51/100.

Its trend is the strongest contributor: the price is 12.89% above its 200-day average, and the 50-day average is 17.86% above the 200-day. The 50-day average is $46.89 and the 200-day average is $39.78. The price has risen 154.59% over the past year.

Only on CleaRank

Figures we compute ourselves from IRDM's own price, earnings and insider-filing history. Tap one to see it in context.

02

IRDM stock price and trading

The chart, today's range and how far the price has moved over each period.

2.0

Trend checks

3/4
  • Price below its 50-day average ›
    The price of $44.91 is 4.2% below the 50-day simple moving average of $46.89.
  • Price above its 200-day average ›
    The price is 12.9% above the 200-day simple moving average of $39.78.
  • 50-day average above the 200-day ›
    The 50-day average ($46.89) is 17.9% above the 200-day average ($39.78), the arrangement of a rising longer-term trend.
  • In the upper half of its 52-week range ›
    The price sits at 70% of its 52-week range, between $15.65 and $57.18.

IRDM share price

Pick a period: each tab shows how far IRDM has moved over it, to the last close.

Nov '25Jan '26Mar '26Jun '26Aug '26Oct '26
Start $17.64 Oct 30, 2025
Latest close $44.91 Oct 30, 2026
High $55.72 Jul 1, 2026
Low $15.84 Nov 20, 2025

Today's trading

Where IRDM sits inside today's range and its 52-week range.

Day range 2.63% wide
$44.91
$44.53 $45.70
52-week range 70% of the way up
$44.91
$15.65 $57.18
Open
$44.86
Previous close
$46.05
Volume
380.20K
44% below average
Market cap
$4.76B
03

IRDM fundamentals and valuation

Valuation against the sector, and the revenue and earnings behind it.

3.0

Valuation and quality checks

2/4
  • P/S above the sector median ›
    The price-to-sales ratio of 5.38 is 115.3% above the sector median of 2.5.
  • Profitable over the last 12 months ›
    Net income over the last 12 months was $93.3M on revenue of $884.2M, a net margin of 10.5%.
  • Missed estimates in most recent reports ›
    IRDM beat the EPS estimate in 2 of its last 5 reports.
  • Pays a dividend ›
    The trailing dividend yield is 1.34%, or $0.6 a share a year.

Key statistics

The headline figures for IRDM.

Market Cap
4.76B
P/E Ratio
N/A
EPS (TTM)
N/A
Dividend Yield
1.34%
52 Week High
57.18
52 Week Low
15.65

As of October 30, 2026, IRDM trades at $44.91, with a market value of $4.76B and a dividend yield of 1.34%.

What the numbers say

CleaRank Financial AI's reading of IRDM's valuation, growth and risks.

Valuation

IRDM is growing more slowly than its sector. The company converts sales into profit with a net margin of 10.5% and an operating margin of 12.87%. Its return on equity of 31.74% is above the sector median of 15.8%. On the balance sheet, debt-to-equity stands at 3.78, and the trailing dividend yield is 1.34%, or $0.60 per share each year.

Earnings & Growth

IRDM's most recent quarterly report, dated October 20, 2026, topped expectations by 185.37%. Reported EPS was $1.17, compared with the $0.41 that analysts had forecast. The shares climbed 0.71% in the following session.

IRDM beat the EPS estimate in 2 of its last 5 reports, though the stock still fell in the first session after 1 of those 2 beats. Earlier, the stock fell 4.81% after the April 23, 2026 report, a miss of 28.57%. Looking ahead, analysts expect EPS of $1.49 this fiscal year (growth of 40.0%) and $1.43 the year after (a decline of 4.4%).

Key risks

IRDM's average daily move is 1.30% with a beta of 0.85 against the S&P 500. The price is 21.46% below its 52-week high of $57.18. Insiders sold $20.4M over the last 18 months and bought $871K, though sales of this kind are often planned in advance and say less than purchases would.

IRDM against the Communication Services sector

How IRDM compares with the median Communication Services stock CleaRank tracks.

P/S ratio 115% above the median
IRDM
5.4x
Sector median
2.5x
Revenue growth, year on year 10.1 points below the median
IRDM
3.8%
Sector median
13.9%
Return on equity 15.9 points above the median
IRDM
31.7%
Sector median
15.8%

Price to sales vs sector: On price-to-sales, the yardstick used here in place of P/E, IRDM trades at 5.38x, +115% versus the sector average of 2.50x.

Return vs XLC: Since May 20, 2025, IRDM has gained 73.9% against a loss of 1.7% for XLC.

Performance against XLC

IRDM and the Communication Services sector fund over the same days.

Jun '25Sep '25Dec '25Apr '26Jul '26Oct '26
IRDM XLC

Revenue and earnings

How much IRDM sells, and how much of it becomes profit.

Revenue, 12 months
$884M
Net income, 12 months
$93.3M
Net margin
10.5%
Revenue growth
+3.8%
Q2 '26, year on year
FY2021-2% marginFY20221% marginFY20232% marginFY202414% marginFY202513% margin
Revenue Net income

The quarterly bars end with Q2 '26 (the quarter to June 30, 2026); IRDM reported again on October 20, 2026, and that quarter is not in our statement data yet. The 12-month figures come from the statistics feed and may include it.

Revenue growth: Revenue grew 4.9% in FY2025 to $872M, from $831M a year earlier.

Profit margin: The net margin was 13.1% in FY2025, down from 13.6% the year before.

Profitable: IRDM earned $114M in FY2025.

Earnings reality check

Did IRDM beat what analysts expected, and how did the stock react?

Beat the estimate
2 of 5
last 5 reports
Fell after a beat
1 of 2
first session after the report
Average surprise
+35.3%
actual EPS against the estimate
Avg. first-session move
-0.6%
the stock, after the report
EPS surprise
First-session move
Apr '25Jul '25Oct '25Apr '26Oct '26

Earnings record: IRDM beat the analyst estimate in 2 of the last 5 quarters.

Market reaction: The stock fell in the first session after 1 of those 2 beats, so a beat has not been enough on its own.

IRDM earnings surprises and the stock's reaction
Report Estimate Actual Surprise First session 5 sessions
Oct 20, 2026after close $0.41 $1.17 +185.37% +0.71% +3.89%
Apr 23, 2026after close $0.28 $0.20 -28.57% -4.81% -4.54%
Oct 23, 2025after close $0.25 $0.35 +40.00% -0.27% -3.02%
Jul 24, 2025after close $0.24 $0.20 -16.67% +1.70% -3.21%
Apr 22, 2025after close $0.28 $0.27 -3.57% -0.19% +11.61%

As of October 30, 2026, IRDM has beaten the analyst EPS estimate in 2 of its last 5 reported quarters and fell in the first trading session after 1 of those beats; its latest report, on October 20, 2026, came in 185.37% above the estimate and the stock moved +0.71% in the first session.

The first session is the first full trading day on the news: the report day itself for a report before the open, the next day for one after the close. Surprise is actual EPS against the consensus estimate.

04

IRDM AI analysis and technical indicators

CleaRank's score and reasoning, the indicators behind it, and what the price moves with.

4.0

Momentum checks

1/3
  • RSI not overbought or oversold ›
    The 14-day RSI is 42.3, in neutral territory.
  • RSI below 50 ›
    An RSI of 42.3 is below the 50 midpoint, so sellers have had the upper hand over the last 14 days.
  • MACD line below zero ›
    The MACD line is negative, so the 12-day average is below the 26-day average.

CleaRank Financial AI analysis of IRDM

The score, the reasoning behind it, and what could move the price next.

Company's health
3/5
12-month analyst target
$47.00
+4.65% above price · median of 7 analysts
AI analyst consensus
51/100
Hold
What the AI sees

Iridium Communications Inc. (IRDM) is giving a mixed trend reading. The stock is at $44.91, which is 4.21% below its 50-day average of $46.89, yet it is 12.89% above its 200-day average of $39.78. Within its 52-week range the price is near the top: it sits 21.46% below the high of $57.18 and 186.96% above the low of $15.65. The 50-day average is 17.86% above the 200-day, so the longer averages have not yet adjusted to the softer recent price.

A recent pullback sits inside a stronger longer record: the price fell 6.24% over the past month, fell 5.13% over the past three months and rose 154.59% over the past year. Volume in the last session ran 44.2% below its average, on a day the price fell 2.48%. The 14-day RSI of 42.3 is in the neutral zone, and the MACD line is negative.

Catalysts
Rewards
  • Earnings beat ›

    The October 20, 2026 report beat the EPS estimate by 185.37%, and the share price rose 0.71% in the first session after it.

    Source: Earnings report, October 20, 2026
Other events
  • Rating reaffirmed ›

    Morgan Stanley kept its Equal-Weight rating on June 30, 2026.

    Source: Analyst action, Morgan Stanley, June 30, 2026
ProTips
  1. The two closest levels to watch are the 20-day EMA at $45.71, which sits above the price, and the 200-day SMA at $39.78, which sits below it.
  2. A 14-day RSI of 42.3 is neutral, and the MACD line is negative. Readings above 70 or below 30 would signal stretched momentum.
  3. After the October 20, 2026 report the share price rose 0.71% in the first session; IRDM beat estimates in 2 of the last 5 reports.
Market outlook

IRDM's trend is mixed. The price is above its 200-day average at $39.78 but under its 50-day average at $46.89. Closing above the 50-day would push both signals up, while closing below the 200-day would push both down. On the way up, the first level met is the 20-day EMA at $45.71. On the way down, the first level met is the 200-day SMA at $39.78.

IRDM's 14-day RSI of 42.3 places it in the neutral zone, between 40 and 60.

Technical indicators

Momentum and trend for IRDM, from its daily closes.

Technical rating Neutral 1 of 4 signals bullish
  • RSI Neutral
  • SMA cross Bullish
  • Price vs SMA Bearish
  • MACD Bearish
Momentum Neutral
42.314-day RSI
Oversold <30 Neutral Overbought >70
MACD (12, 26) -0.641 Bearish
Trend Golden cross
-4.2%price against the 50-day average
200-day $39.78 50-day $46.89 Price $44.91
Price against the 200-day +12.9% Bullish

As of October 30, 2026, with IRDM at $44.91, its 14-day RSI is 42.3 (neutral territory), its 50-day simple moving average is $46.89 and its 200-day is $39.78.

Calculated by CleaRank on daily closes as of October 30, 2026: Wilder's 14-day RSI, 50- and 200-day simple moving averages, MACD line (12, 26). How we calculate these

What IRDM moves with

Correlation of daily returns over one year: +1 moves in step, 0 has no link, -1 moves the opposite way.

-1 0 +1
S&P 500 (SPY) +0.28 Weak
Nasdaq 100 (QQQ) +0.27 Weak
Bitcoin (BTC) +0.18 Weak
Gold (XAU) +0.10 Weak

As of October 30, 2026, IRDM's 1-year correlation of daily returns is +0.28 with S&P 500 (SPY), +0.27 with Nasdaq 100 (QQQ), +0.18 with Bitcoin (BTC) and +0.10 with gold (XAU).

Check any other asset
Try
05

IRDM price target and analyst forecast

The analysts' target range and how their ratings split.

5.0

Analysts checks

1/3
  • Fewer than half of analysts rate it a buy ›
    3 of 7 analysts rate it a buy or strong buy, 4 a hold and 0 a sell.
  • Median target above the price ›
    The median 12-month target of $47.00 is 4.7% above the price.
  • No more buy ratings than three months ago ›
    3 of 7 rate it a buy now, against 6 of 10 three months ago.

IRDM Wall Street View

12-month price targets

Low $36.00 Median $47.00 (+4.7%) High $54.00

Ratings

Buy 3 Hold 4 Sell 0 3 months ago: 6 of 10 buy

Recent rating actions

Recent analyst rating actions on IRDM
Date Firm Action Rating
Jun 30, 2026 Morgan Stanley Maintains Equal-Weight
Jun 3, 2026 Oppenheimer Maintains Outperform

As of October 30, 2026, 7 Wall Street analysts cover IRDM: 3 rate it a buy or strong buy, 4 a hold and 0 a sell or strong sell. Their 12-month price targets range from $36.00 to $54.00. The median IRDM price target is $47.00, 4.7% above the price of $44.91.

Source: TwelveData analyst consensus. Targets and ratings belong to the analysts, not to CleaRank.

06

IRDM trade plan: entry, stop loss and targets

Entry, stop and target levels from the moving averages and recent volatility. Educational, not advice.

IRDM trade plan

Entry, stop and target levels, sized to your account. Change the bias or the risk and every level updates.

Your bias
Risk per trade 1%
Conservative Aggressive
Portfolio value
$
Position size: Enter portfolio size →

Entry Strategies pick an entry style

Conservative
$44.46
Slight discount to current
Lower entry level
Aggressive
$44.91
At current price
Entry at the current price

Risk management

Stop loss
$42.71
Max loss
-3.9%
Volatility-adjusted stop Set from the RSI (42.3) and recent volatility.

Profit targets (Based on Conservative Entry)

Target 1
$45.79
+3% (Conservative) +2.0% (Aggressive)
Target 2
$46.68
+5% (Conservative) +4.0% (Aggressive)
Target 3
$48.02
+8% (Conservative) +6.9% (Aggressive)

These levels come from IRDM's moving averages and recent volatility, not from a forecast. Educational levels, not financial advice; the full disclaimer is at the foot of the page.

Risk profile

How much IRDM tends to move, against the market and on its own.

Beta
0.85
against the S&P 500; 1 moves with the market
Daily volatility
1.30%
30-day standard deviation
52-week range
$44.91
$15.65 70% of the way up $57.18

Compare IRDM

Put IRDM side by side with other stocks and benchmarks.

07

IRDM price history and drawdowns

IRDM's worst falls and recoveries, what $10,000 became, and which months have been kind to it.

7.0

Track record checks

3/4
  • Average daily move under 2% ›
    The price has moved 1.30% on an average day (30-day standard deviation of daily returns).
  • Not yet recovered from its worst fall ›
    The worst fall was 74.0%, from February 2023 to November 2025; the price is still 26.1% below that peak.
  • Most 1-year holds ended higher ›
    67% of 1-year holding periods in the last 10 years ended with a gain.
  • Beat the S&P 500 since the chart begins ›
    $10,000 invested in October 2016 is now worth $58,906, against $41,607 in the S&P 500 (SPY).

IRDM Drawdowns & Recovery

Worst fall, last 10 years
-74.0%
February 2023 to November 2025
Recovery
Not yet
still 26.1% below the February 2023 peak
From the 10-year high
-26.1%
highest close, February 2023
1-year holds that gained
67%
of every 1-year window

As of October 30, 2026, IRDM's worst peak-to-trough fall over the last 10 years with dividends reinvested was -74.0% (February 2023 to November 2025); it is still 26.1% below that peak, and 67% of 1-year holding periods ended with a gain.

From weekly closing values with dividends reinvested. A drawdown is the fall from the highest value reached so far to a later low.

Growth of $10,000

What $10,000 put into IRDM in October 2016 is worth now, against the same amount in the S&P 500.

IRDM today
$58,906
from $10,000 in October 2016, dividends reinvested
S&P 500 today
$41,607
the same $10,000 in SPY
Ahead of the index by
$17,300
1.4x the index result
Total change
+489%
5.9x the starting amount
20182020202220242026
IRDM S&P 500 (SPY)

Against the market: IRDM beat the S&P 500 over this period: $58,906 against $41,607.

A $10,000 investment in IRDM in October 2016 would be worth about $58,906 today with dividends reinvested, compared with about $41,607 for the same investment in the S&P 500 benchmark (also with dividends reinvested).

Seasonal patterns

Which calendar months have been kind to IRDM, and which have not.

Jan8/10 upFeb6/10 upMar5/10 upApr7/10 upMay3/10 upJun7/10 upJul6/10 upAug5/10 upSep3/10 upOct3/9 upNov5/10 upDec6/10 up

Strongest month, January: an average of +6.26%, up in 8 of 10 years.

Weakest month, September: an average of -3.86%, up in 3 of 10 years.

This month, October: has averaged +2.05%, up in 3 of 9 years. Past seasonality does not repeat on schedule.

Over the last 10 years, IRDM's strongest calendar month has been January (average +6.26%, up in 8 of 10 years) and its weakest September (average -3.86%, up in 3 of 10 years).

Average return for each calendar month over the last 10 years, from weekly closing prices with dividends included.

08

IRDM stock price prediction 2030

Thousands of simulated paths from the price history. A range of outcomes, not a forecast.

Monte Carlo projection

Thousands of simulated paths for $10,000 in IRDM, from its own past volatility. The shaded area holds 80% of them.

Downside, 2030
$4,490
10th percentile
Base case, 2030
$14,642
median path
Upside, 2030
$47,751
90th percentile
20262027202820292030
Upside (90th) Base case (median) Downside (10th) 10th to 90th percentile

CleaRank's 4-year Monte Carlo simulation, based on 10 years of price history, projects that a $10,000 investment in IRDM today could grow to about $14,642 by 2030 in the base case, with a 90th-percentile outcome near $47,751 and a 10th-percentile outcome around $4,490. The simulation models price only; at today's 1.34% yield, dividends would add to these figures. Projections are statistical simulations, not guarantees.

IRDM Stock Price Prediction 2030: Simulated Scenarios

The same simulation in share prices, year by year.

Price today
$44.91
Base case, 2030
$65.76
1.5x over 4 years
Range, 2030
$20.16 to $214
10th to 90th percentile

CleaRank's simulation projects a price near $65.76 for IRDM by 2030 in the base case, from $44.91 today (1.5x over 4 years). The 10th-percentile path ends near $20.16. These are outcomes of a Monte Carlo simulation run on IRDM's historical return distribution, not price targets, and they assume no dividends are reinvested.

IRDM simulated price paths by year
Year 10th percentile Base case 90th percentile range base today
2027 $27.36 $49.40 $89.21
2028 $23.56 $54.34 $125
2029 $21.48 $59.78 $166
2030 $20.16 $65.76 $214

Method: a lognormal simulation of IRDM's own volatility and capped historical trend, re-run daily; base case is the median path, the outer columns the 10th and 90th percentiles. How the simulation works

09

IRDM insider trading

What the people running the company have bought and sold.

IRDM insider trading

Shares the company's directors and officers bought and sold, from their own filings.

Bought
$871K
2 open-market purchases
Sold
$20.4M
12 open-market sales
Insiders filing
18
over the last 18 months
Average trade
$1.5M
buys and sales together

Month by month

Open-market purchases above the line, sales below.

May '25Aug '25Nov '25Feb '26May '26Aug '26Oct '26

Net insider selling: Insiders bought $871K on the open market and sold $20.4M.

As of October 30, 2026, IRDM insiders reported 12 open-market sales worth $20.4M and 2 open-market purchases worth $871K over the last 18 months; grants and option exercises are not counted.

Insider transactions in IRDM
Date Insider Type Shares Value
Sep 30, 2026
Thomas C Canfield
Director
Grant 733 -
Sep 30, 2026
Thomas J Fitzpatrick
Director
Grant 55 -
Sep 30, 2026
Robert H Niehaus
Director
Grant 55 -
Sep 30, 2026
Jacqueline E Yeaney
Director
Grant 34 -
Sep 15, 2026
Timothy James Last
Officer
Sell 5.8K $267.4K
Sep 3, 2026
Timothy James Last
Officer
Sell 2.0K $95.3K
Aug 20, 2026
Suzanne E Mcbride
Officer and Director
Grant 17.4K -
Aug 18, 2026
Thomas J Fitzpatrick
Director
Sell 224.3K $11.2M
Aug 17, 2026
Suzanne E Mcbride
Chief Operating Officer
Sell 85.5K $4.3M
Aug 17, 2026
Kathleen A Morgan
Officer
Sell 33.2K $1.7M
Page 1 of 8

Source: TwelveData, from SEC Form 4 filings

10

IRDM stock forecast: questions people ask

Answered from the figures on this page, as of October 30, 2026.

IRDM Forecast: Frequently Asked Questions

Is Iridium Communications Inc. (IRDM) a buy right now?
At 51/100, IRDM lands in CleaRank's Hold band. The trend does the most to lift the score, since the price is 12.89% above its 200-day average, and the 50-day average is 17.86% above the 200-day. This describes the data on this page and is not a personal recommendation.
How has Iridium Communications Inc. (IRDM) performed over the past year?
The price has climbed 154.59% across the past year. Shorter stretches tell a weaker story, with a drop of 5.13% over three months and a fall of 6.24% in the last month. Today it sits 21.46% under its 52-week high of $57.18.
What are the key price levels for IRDM?
Overhead, the first levels the price meets are the 20-day EMA at $45.71 and the 50-day SMA at $46.89. On the downside, the first supports are the 200-day SMA at $39.78 and, further down, the 52-week low at $15.65.
Is IRDM expensive compared with Communication Services stocks?
These medians are drawn from 19 stocks across the entire sector, not just direct rivals.
Does IRDM pay a dividend?
Yes, IRDM pays a dividend. Its trailing yield is 1.34%, equal to $0.60 a share per year. Because the yield is the dividend divided by the share price, it moves whenever either of those figures changes.
What do Wall Street analysts think of IRDM?
Among the 7 analysts who cover IRDM, 3 recommend buying it, 4 recommend holding and 0 recommend selling. The median 12-month price target is $47.00, which is 4.7% above the current price.
How often has IRDM beaten earnings estimates?
IRDM beat the EPS estimate in 2 of the last 5 reports in our data. The share price fell in the first session after 1 of those 2 beats.
How volatile is IRDM?
On an average day IRDM's price moves 1.30%, based on the 30-day standard deviation of daily returns. Against the S&P 500, its beta is 0.85.
Are IRDM insiders buying or selling?
Insiders sold $20.4M of stock over the last 18 months and made open-market purchases worth $871K. Many sales are planned ahead or made to cover taxes on vesting shares, so they tell an investor less than buying does.
What is the 52-week range of IRDM?
Over the past 52 weeks, IRDM has traded between $15.65 and $57.18. At $44.91, the stock sits at 70% of that span, 186.96% above the low and 21.46% below the high.

Disclaimer: CleaRank.com is a financial data and analytics provider, not a registered investment advisor, broker-dealer, or financial regulatory body. The stock analysis, trade plans, and AI-generated signals presented for IRDM are for educational and informational purposes only and do not constitute financial advice, investment recommendations, or an offer to buy or sell any securities. All trade setups and performance metrics shown are hypothetical, hindsight-based, and simulated. They do not represent actual trades made by CleaRank or its affiliates. Stock prices can be volatile and are subject to market, economic, and company-specific risks. Market data is provided "as-is" and may be delayed by 15 minutes or more. We do not guarantee the accuracy, completeness, or timeliness of any data. You should never invest money you cannot afford to lose. Past performance does not guarantee future results. Consult a qualified financial advisor before making any investment decisions. Analysis generated on October 31, 2026.

Disclaimer:

Engaging in financial markets carries significant risk of total capital loss. Markets are volatile, unpredictable, and past success does not guarantee future results. Never invest funds you cannot afford to lose. CleaRank does not offer financial, investment, or advisory services. We provide no recommendations, endorsements, or guarantees regarding market outcomes. You alone are responsible for your decisions.

Advertiser Disclosure:

At CleaRank, clarity and transparency are more than ideals, they are the core of our operations. CleaRank is a paid SaaS platform: the Pro and Ultra workbench plans are paid subscriptions, while everything else on this site, including our trading calculators, tools and market news, is free to use. In the spirit of full disclosure: some of our free editorial content contains partner links, and we may earn affiliate commissions from them. This never affects what you pay. Please keep in mind that your confidence in our platform is what matters to us most and we are devoted to earning your trust every day through consistent transparency. CleaRank's Editorial team works independently from partner relationships and financial incentives. All material and information made available by CleaRank stem from our unique technology and methodology which are created to prioritize your needs as a trader and deliver actionable insights to help you make clearer decisions.